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8753ES Option 011 Network Analyzer User`s

1. REPE eee CENTERS 234 088 808 MHz SPAN 15 0080 802 MHz CENTER 134 000 MHz SPAN 15 0980 8 MHz pg6229 Setting the CW Frequency 1 To place a marker at the desired CW frequency press and either turn the front panel knob or enter the value followed by a unit terminator 2 Press Seq SPECIAL FUNCTIONS MKR gt CW You can use this function to set the marker to a gain peak in an amplifier After pressing MKR gt CW FREQ activate a CW frequency power sweep to look at the gain compression with increasing input power 1 38 Making Measurements Using Markers To Search for a Specific Amplitude These functions place the marker at an amplitude related point on the trace If you switch on tracking the analyzer searches every new trace for the target point Searching for the Maximum Amplitude 1 Press Marker Search to access the marker search menu 2 Press SEARCH MAX to movethe active marker to the maximum point on the measurement trace Figure 1 28 Example of Searching for the Maximum Amplitude Using a Marker CH1 S2 log MAG 18 dB REF 45 dB i 23 258 dE 128 sa ede mHz MARKER 1 4 i CENTER 134 800 20G MHz SPAN 38 888 B20 MHz aw000051 Searching for the Minimum Amplitude 1 Press Marker Search to access the marker search menu 2 Press SEARCH MIN to
2. Feature 8753D 8753E 8753ES Option 011 Option 011 Option 011 Fully integrated measurement system built in test set No No No Test port power range dB m a a a Auto manual power range selecting No No No Port power coupling uncoupling No No No Internal disk drive Yes Yes Yes Flash EPROM No Yes Yes Precision frequency reference Option 1D5 Yes Yes Yes Frequency range low end in KHz 30 300 30 300 30 300 Ext frequency range to 6 GHz Option 006 Yes Yes Yes 75Q system impedance Option 075 a a a TRL LRM correction Yes Yes Yes Power meter calibration Yes Yes Yes Interpolated error correction Yes Yes Yes E nhanced response calibration No Yes Yes Maximum error corrected measurement points 1601 1601 1601 Configurable test set Option 014 N A N A N A Segmented error correction in frequency list mode Yes Yes Yes Swept list frequency sweep No Yes Yes Sweep speed 201 points one port cal ms 200 77 70 Sweep speed 201 points full 2 port cal 510 145 121 Speed in time domain transform 350 46 42 Data I O speed GPIB ms internal binary 35 11 16 Four parameter display No Yes Yes Markers display channel 4 5 5 Total viewable markers at any time 8 20 20 7 91 Operating Concepts Differences between 8753 Network Analyzers Table 7 7 Comparing the 8753D E ES Option 011 Network Analyzers Continued
3. i CENTER 134 800 890 MHz SPRN 35 9000 B G MHz aw000030 To switch on the corresponding marker and make it the active marker press MARKER2 MARKER 3 MARKER 4 0r MARKER 5 All of the markers other than the active marker become inactive and are represented on the analyzer display as A The active and inactive markers are shown in Figure 1 13 1 25 Making Measurements Using Markers Figure 1 13 Active and Inactive Markers Example CH1 S21 log MAG 10 dB REF 50 dB 2 3 23 689 dB tal 127 960 OGO MHz PRm 4 3 13 um 111 4 133 5M 3 23J614 13915 n 4 68 783 B 145 975 MH 436 9M 5 3 H Bs No Na Na Na wo Cor i 68 150 7 MM M CENTER 134 000 000 MHz SPAN 50 000 000 MHz pa5109e Toswitch off all of the markers press ALL OFF To Move Marker Information Off the Grids If marker information obscures the display traces you can turn off the softkey menu and move the marker information off the display traces and into the softkey menu area Pressing the backspace key performs this function This is a toggle function Pressing alternately hides and restores the current softkey menu The softkey menu is also restored when you press any softkey or a hardkey which leads to a menu 1 Set up a four graticule display as described in Viewing Four Measurement Channels on page 1 14 2
4. HPGL 2 Printer Lotus Applications Pen Number Color Pen Number Color 0 white N A N A 1 cyan aqua 1 black 2 magenta red violet 2 red 3 blue 3 green 4 yellow 4 yellow 5 green 5 blue 6 red 6 red violet magenta 7 bl ack 7 aqua cyan To modify the color or font size consult the documentation for the particular application being used NOTE Plot files may also be saved to a floppy disk as a J PEG file and used on a personal computer Refer to Saving in Graphical J PEG Form on page 4 45 4 20 Printing Plotting and Saving Measurement Results To View Plot Files on a PC Using Ami Pro To view plot files in Ami Pro perform the following steps 1 From the FILE pull down menu select IMPORT PICTURE 2 In the dialog box change the File Type selection to HPGL This automatically changes the file suffix in the filename box to PLT NOTE The network analyzer does not use the suffix P LT so you may want to change the filename filter to or some other pattern that will allow you to locate the files you wish to import 3 Click OK to import the file 4 Thenext dialog box allows you to select paper type rotation landscape or portrait and pen colors You will probably need to change pen colors NOTE Thenetwork analyzer uses pen 7 for text The default color in Ami Profor pen 7 is aqua which is not very readable against the typical white background You may want to chan
5. START 300 000 MHz STOP 3 000 000 000 MHz CH4 START O s STOP 40 ns a Frequency Domain b Time Domain Bandpass pg6198 c Thetime domain measurement shows the effect of each discontinuity as a function of time or distance and shows that the test device response consists of three separate impedance changes The second discontinuity has a reflection coefficient magnitude of 0 035 i e 3 596 of the incident signal is reflected Marker 1 on the time domain trace shows the elapsed time from the reference plane where the calibration standards are connected to the discontinuity and back 18 2 nanoseconds The analyzer has three frequency to ti me transform modes Time domain bandpass mode simulates the time domain response of an impulse input and is designed to measure band limited devices Although this mode is the easiest to use it results in less time domain resolution than low pass mode and may result in some magnitude errors at low frequencies when gating is used For devices that are not band limited one of thelow pass modes is recommended Time domain low pass step mode simulates the time domain response of a step input As in a traditional TDR measurement the distance to the discontinuity in the test device and the type of discontinuity resistive capacitive inductive can be determined Time domain low pass impulse mode simulate
6. CENTER 134 008 988 MHz SPRN z 880 a8 MHz aw000007 Group delay measurements may require a specific aperture A F or frequency spacing between measurement points The phase shift between two adjacent frequency points must be less than 180 otherwise incorrect group delay information may result 4 Tovary the effective group delay aperture from minimum aperture no smoothing to approximately 196 of the frequency span press SMOOTHING ON When you increase the aperture the analyzer removes fine grain variations from the response It is critical that you specify the group delay aperture when you compare group delay measurements 1 47 Making Measurements Measuring Electrical Length and Phase Distortion Figure 1 38 Group Delay Example Measurement with Smoothing CHL Spy delay BB ns REF s i Cor De SMOOTHING APERTURE 1 SPAM Smo 3B kHz L CENTER 134 888 O MHz SPAN 2 028 BAB MHz aw000008 5 Toincrease the effective group delay aperture by increasing the number of measurement points over which the analyzer calculates the group delay press SMOOTHING APERTURE As the aperture is increased the smoothness of the trace improves markedly but at the expense of measurement detail Figure 1 39 Group Delay Example Measurement with Smoothing Aperture Increased CH1 Sg1 delay 5B ns REF A s he e SMOOTHING AP
7. PLOT FPX l L JL IL OPTIONAL CHARACTER THAT INDICATES THE FILE _ S PART OF A MULTIPLE FILE PLOT ON THE USER GENERATED SAME GRATICULE OUTPUT FORMAT CODE THAT INDICATES THE PLOT QUADRANT POSITION OR FULL PAGE FP FULL PAGE DEFAULT LU LEFT UPPER QUADRANT AUTO GENERATED LL LEFT LOWER QUADRANT RU RIGHT UPPER QUADRANT RL RIGHT LOWER QUADRANT PLOT FILES SEQUENCE NUMBER 8 TO 31 ROOT OF FILENAME ph646c To Output the Plot Files You can plot the files to a plotter from a personal computer You can output your plot files to an HPGL compatible printer by following the sequence in Outputting Plot Files from a PC to an HPGL Compatible Printer on page 4 23 You can run a program that plots all of the files with the root filename of PLOT to an HPGL compatible printer This program is provided on the CD ROM of example programs that is included in the programmer s guide However this program is for use with LIF formatted disks and is written in HP BASIC 4 12 Printing Plotting and Saving Measurement Results Defining a Plot Function Defining a Plot Function 1 Press Copy DEFINE PLOT Choosing Display Elements Choose which of the following measurement display elements that you want to appear on your plot Q Choose PLOT DATA ON if you want the measurement data trace to appear on your plot d Choose PLOT MEM ON if you want the displayed memory trace to appear on your
8. C T m t CH1 START 1 000 A MHz STOP 1 808 000 A MHz D2 D1 log MAG 1 dB REF dB 1 1 0359 dB PORT POWER CH2 START 1 466 888 MHz STOP 1 888 680 BAA MHz 12 1f COUPLED CH OFF was selected recouple the channel stimulus by pressing COUPLED CH ON 13 To place the marker exactly on a measurement point press MARKER MODE MENU MARKERS DISCRETE 14 To set the CW frequency before going into the power sweep mode press SPECIAL FUNCTIONS MARKER CW 15 Press Sweep Setup SWEEP TYPE MENU POWER SWEEP If interpolation is on the default setting the calibration will be applied to the power Sweep 16 Enter the start and stop power levels for the sweep Now channel 1 is displaying a gain compression curve Do not pay attention to channel 2 at this time 17 Press DUAL QUAD SETUP DUAL CHANNEL ON 18 f D2 D1to D2ON was selected press MORE D2 D1toD2OFF 19 Press Meas INPUT PORTS B Now channel 2 displays absolute output power in dBm as a function of power input m SCALE DIV to changethe scale of channel 2 to 10 dB per ivision 21 Press to change the scale of channel 1 to 1 dB per division 1 61 Making Measurements Measuring Amplifiers NOTE A receiver calibration will improve the accuracy of this measurement Refer to Chapter 6 Calibrating for Increased Measurement Accuracy 22 Press MARKER MODE MENU MARKERS COUPLED
9. Feature 8753D 8753E 8753ES Option 011 Option 011 Option 011 Color display Yes Yes Yes Flat panel LCD No Yes Yes VGA output No Yes No Delete display Option 1DT No Yes No Test sequencing Yes Yes Yes Automatic sweep time Yes Yes Yes External source capability Yes Yes Yes Tuned receiver mode Yes Yes Yes Printer plotter buffer Yes Yes Yes Harmonic measurements Option 002 Yes Yes Yes Frequency offset mode mixer measurements Yes Yes Yes dc bias to test device _a _a a Interfaces RS 232 parallel and DIN keyboard Yes Yes Yes User defined preset Yes Yes Yes Non volatile memory in Kbytes 512 2000 2000 Dynamic range 30 kHz 3 GHz 100 dB 100 dB 100 dB Dynamic range 3 GHz 6 GHz 110 dB 110 dB 110 dB Real time clock Yes Yes Yes a For this network analyzer the feature is dependent on the test set being used b 300 kHz to 3 GHz without Option 006 30 kHz to 6 GHz with Option 006 7 92 8 Safety and Regulatory Information 8 1 Safety and Regulatory Information General Information General I nformation Maintenance Clean the cabinet using a dry or damp cloth only WARNING To prevent electrical shock disconnect the analyzer from mains before cleaning Use a dry cloth or one slightly dampened with water to clean the external case parts Do not attempt to clean internally Assistance Product maintenance agreements and other customer assistance agreements are available for Agilent Technolo
10. CENTER 134 000 000 MHz SPAN 2 000 000 MHz pa5105e Group Delay The phase linearity of many devices is specified in terms of group or envelope delay The analyzer can translatethis information into a related parameter group delay Group delay is the transmission time through your device under test as a function of frequency Mathematically it is the derivative of the phase response which can be approximated by the following ratio A 360 x Ao where A is the difference in phase at two frequencies separated by AF The quantity AF is commonl y called the aperture of the measurement The analyzer calculates group delay from its phase response measurements 1 46 Making Measurements Measuring Electrical Length and Phase Distortion The default aperture is the total frequency span divided by the number of points across the display i e 201 points or 0 596 of thetotal span in this example 1 Continue with the same instrument settings and measurements as in the previous procedure Deviation From Linear Phase 2 To view the measurement in delay format as shown in Figure 1 37 press DELAY Scale Ref SCALE DIV x cx 3 To activate a marker to measure the group delay at a particular frequency press and turn the front panel knob or enter a value from the front panel keypad Figure 1 37 Group Delay Example Measurement CHi 8g delay SB ns REF Gs r Cor Dat
11. System Zo Calibration Kit Label Disk File Name STANDARD co C1 C2 C3 FIXED TERM OFFSET FREQ GHz COAX STND x10715 x10727 x106 x105 SLIDING IMPED or LABEL NO TYPE F Fiz Fm EH2 0 E DELAY Z L ic 2 OFFSET 0 OSS MIN MAX s Q O s 1 2 3 4 5 6 7 8 a Ensure system Zp of network analyzer is set to this value b Open short load delay thru or arbitrary impedance c Open standard types only d Load or arbitrary impedance only e Arbitrary impedance only device terminating impedance Each standard must be identified as one of five types open short load delay thru or arbitrary impedance 7 58 Operating Concepts Modifying Calibration Kits After a standard number is entered selection of the standard type will present one of five menus for entering the electrical characteristics model coefficients corresponding to that standard type such as OPEN These menus are tailored to the current type so that only characteristics applicable to the standard type can be modified The following is a description of the softkeys located within the define standard menu OPEN defines the standard type as an open used for calibrating reflection measurements Opens are assigned a terminal impedance of infinite ohms but delay and loss offsets may still be added Pressing this key also brings up a menu for defining the open induding its capacitance
12. Stepped Edit List Menu The EDIT LIST softkey within the sweep type menu provides access to the edit list menu This menu is used to edit the list of frequency segments subsweeps defined with the edit subsweep menu described next U p to 30 frequency subsweeps can be specified for a maximum of 1601 points The segments do not have to be entered in any particular order the analyzer automatically sorts them and shows them on the display in increasing order of start frequency This menu determines which entry on the list is to be modified while the edit subsweep menu is used to make changes in the frequency or number of points of the selected entry Stepped Edit Subsweep Menu Usingthe EDIT or ADD softkey within the edit list menu will display the edit subsweep menu This menu lets you select measurement frequencies arbitrarily Using this menu it is possible to define the exact frequencies to be measured on a point by point basis For example the sweep could include 100 points in a narrow passband 100 points across a broad stop band and 50 points across the third harmonic response The total sweep is defined with a list of subsweeps 7 16 Operating Concepts Sweep Types The frequency subsweeps or segments can be defined in any of the following terms start stop number of points start stop step center span number of points center span step CW frequency The subsweeps can overlap and do not have to be ent
13. 20 000 nan MH STOP 1 080 086 BAA MH 20 000 aan MHz STOP 1 0O 00O Baa MHz pg6239 Figure 1 44 2nd and 3rd Harmonic Distortion in dBc 21 Jun 1994 12 45 43 log MAG 10 dB REF dB 1 45 343 dB log MAG 1 dB REF dB L 71 292 dB S5aa hao ada MHz L FL Pd 1 3rd Hamonic dBc dis d Hamonic dBc 20 000 A MHz STOP 1 80 908 A MHz pg6240 CH1 START CH2 START 1 54 20 000 800 MHz STOP 1 980 080 680 MHz Making Measurements Measuring Amplifiers Making Harmonic Measurements Perform the following steps to display the absolute power of the fundamental and second harmonic in dBm 1 O O N O Press INPUT PORTS B to measure the power for the fundamental frequencies Press INPUT PORTS B tomeasurethe power for the harmonic frequencies Set the start frequency to a value greater than 16 MHz Press and select COUPLED CH OFF Uncoupling the channels allows you to have the separate sweeps necessary for measuring the fundamental and harmonic frequencies Press and select CHAN POWER COUPLED Coupling the channel power allows you to maintain the same fundamental frequency power level for both channels Press and set the power level for both channels Press DUAL QUAD SETUP and select DUAL CHAN ON Press and position marker to desired frequency Press HARMONIC MEAS SECOND You can view both the fundamental power and harmonic power levels at the same time Refer to Figure 1 45 Figure
14. 00 cece 4 28 Titling the Displayed Measurement 0 000 cece nen 4 30 Configuring the Analyzer to Produce a Time Stamp ccc eee eee eee 4 31 Abor ungaPrntor PIO Process aac kd cede dewe needa nie bad Ad PESE PEduG pei dad 4 31 Printing or Plotting the List Values or Operating Parameters Lus 4 32 If You Want a Single Page of Values ics ese ecd ceded et ddr E REAERRERRREPEEG RE 4 32 IT You Want the Entre List pf VEINS aaaexaderxadais4 PCIGA3Ga4 ebEI1qoerEqu ed 4 32 Solving Problems with Printingor Pletting ssessesndestssekukectkER RRERR EFE ERES 4 33 Saving and Recalling Instrument States 0 00 0 eee 4 34 Places Where You Cat Save oai Le ebeGeeti dee ERR ART RPERERE REP ISPTEPEPA eae 4 34 Contents What You Can Save tothe Analyzer s Internal Memory asussaan 4 34 What fou Can Save toa Floppy DISK 12xx4 Xara brCeYpbre 3 Rd PRGSR R A p Ed PERS 4 35 What You Can Save Loa Comte iede seu cncewdeene ss be ONE HE E ERE ER EEI Ei 4 35 SVN am nstr ment SUEB ute Re Sed ORE ad aded dde Pase Re oO She MX EG 4 36 Saving Measurement Resulis iiasd r ieee VERA EREESEYRUEERRER EA NAA RERRRERE OR ERA E 4 37 AoA Daa EOS ussxadguxaqaeqqqxadde qu pExadamqeep pieberiks s adic iqees4dad 4 40 Saving ut Textual CSV FOU iuis osazuetkbb rh iR reber q EDIKE PAP RR Pap EG E Fd 4 43 Saving it Graphical U PEGI FOM es iua oda Ce WR dee EXCERPT EHE a b RO 4 45 Instrument Stata Fes adiac RERAI AIRE RR ERI
15. MARKERS LIMIT TESTING pb6101d NOTE If the analyzer has an active two port measurement calibration all four S parameters will be saved with the measurement results All four S parameters may be viewed if the raw data array has been saved 1 If you want totitle the displayed measurement refer to Titling the Displayed Measurement on page 4 30 2 Press SELECT DISK 3 Choose one of the following disk drives e INTERNAL DISK e EXTERNAL DISK If necessary refer tothe external disk setup procedure in Saving an Instrument State on page 4 36 4 Press DEFINE DISK SAVE 5 Definethe save by selecting from the following choices L1 DATA ARRAY ON 1 RAW ARRAY ON 4 38 Printing Plotting and Saving Measurement Results Saving Measurement Results Li FORMAT ARY ON If you select DATA ARRAY ON RAW ARRAY ON or FORMAT ARY ON the data is stored to disk in IEEE 64 bit real format for LIF disks and 32 bit PC format for DOS disks This makes the DOS data files half the size of the LIF files NOTE Selecting DATA ARRAY ON may store data to disk in the S2P ASCII data format See ASCII Data Formats on page 4 40 T GRAPHICS ON If you select GRAPHICS ON theuser graphics area is saved Refer to the programmer s guide for information on using display graphics The measurement display is not saved with this selection Refer to If You Are Plotting Measurement Results to a Disk Drive on page 4 11 to plot measu
16. For K36 mode press SELECT RX ANT For K39 mode press SELECT PORTS 2 3 12 Perform a full two port calibration on channel 2 NOTE Make sure you connect the standards to the Rx port of the test adapter or a cable attached toit for FORWARD calibrations and tothe Ant port for REVERSE calibrations 13 Savethis state in the analyzer Press Save Recall SAVE STATE 14 Connect the duplexer to the test adapter 15 Set up a 2 graticule 4 parameter display with transmission measurements on the top graticule and reflection measurements on the bottom grati cule Press DUAL QUAD SETUP 4 PARAM DISPLAYS SETUPB Trans REV S12 A R Refl REV S22 B R Trans F WD S21 B R Refl FWD S11 A R then set DUAL CHAN on OFF toON The display will be similar to Figure 1 41 Figure 1 41 Duplexer Measurement 5 Aug 1998 13 10 11 CHi S24 LOG 18 dB REF 40 dB CH2 12 LOG 16 SR 40 dB Refl FWD ae T S11 A D Se Trans FWD 21 B R Trans REV 12 ACR Refl REV 822 B R CH3 11 LOG 18 dB REF 8 dB CH4 22 LOG 16 dB REF 8 dB ANALOG IN Aux Input CONVERSION COFF INPUT CH1 CH3 CENTER 860 000 00A MHz SPAN 120 000 00A MHz PORTS CH2 CH4 CENTER 860 900 000 MHz SPAN 128 088 000 MHz 1 51 Making Measurements Characterizing a Duplexer Normally a 2 port calibration requires a forward and reverse sweep to complete before the displayed trace updates For faster tuning it is possible to set t
17. As a reflection standard an open termination offers the advantage of broadband frequency coverage At RF and microwave frequencies however an open rarely has perfect reflection characteristics because fringing capacitance effects cause phase shift that varies with frequency This can be observed in measuring an open termination after calibration when an arc iin the lower right circumference of the Smith chart indicates capacitive reactance These effects are impossible to eliminate but the calibration kit models indude the open termination capacitance at all frequencies for compatible calibration kits The capacitance model is a cubic polynomial as a function of frequency where the polynomial coefficients are user definable The capacitance model equation is C CO C1xF C2xF C3 x F3 where F is the measurement frequency The terms in the equation are defined with the specify open menu as follows CO allows you to enter the CO term which is the constant term of the cubic polynomial and is scaled by 10 1 Farads C1 allows you to enter the C1 term expressed in F Hz Farads Hz and scaled by 107 C2 allows you to enter the C2 term expressed in F H z and scaled by 1036 C3 allows you to enter the C3 term expressed in F H z and scaled by 10 SHORT defines the standard type as a short for calibrating reflection measurements Shorts are assigned a terminal impedance of 0 ohms but delay and loss offsets ma
18. Noticethat the LOADS softkey is now underlined 11 Repeat the open short load measurements described in the previous steps but connect the devices in turn to PORT 2 and usethe REVERSE OPEN REVERSE SHORT and REVERSE LOADS softkeys Include any adapters that you would include in your device measurement 12 To compute the reflection correction coefficients press STANDARDS DONE 13 To start the transmission portion of the correction press TRANSMISSION 6 30 Calibrating for Increased Measurement Accuracy Full Two Port Error Correction 14 Make a thru connection between the points where you will connect your device under test as shown in Figure 6 9 NOTE NOTE Indude any adapters or cables that you will havein the device measurement That is connect the standard device where you will connect your DUT Thethru in most calibration kits is defined with zero length The correction will not work properly if a non zero length thru is used unless the calibration kit is modified to change the defined thru to the length used This is important for measurements of non insertable devices devices having ports that are both male or both female The modified calibration kit must be saved as the user calibration kit and USER KIT must be selected beforethe calibration is started 15 To measure the standard when the trace has settled press DO BOTH FWD4REV The analyzer underlines the softkey label after it makes each measuremen
19. 0200e ees 4 17 Plotting Multiple Measurements Per Page Using a Pen Plotter 5 4 18 If You Are Plotting to an HPGL Compatible Printer 00 0c eee ease 4 19 TO View PIG Files OTe PG 1ebbrepprostebctkqnpbbReRR 4G d he booed eS A REEY E YRPA d RSS 4 20 Weasel Mal ua acid wd FUR ob deed ee re ee ee ee VP ded PE he ee PE ed 4 21 Usna Feehan cies a darbpbradoe Fee howe ede eb CC EROR HDEOCE ede EORR ER HORDE 4 21 Converting HPGL Files for Use with Other PC Applications 0 4 22 Outputting Plot Files froma PC toa Plotter aiissetek aed ERA RESP ERA PER 4 22 Outputting Plot Files from a PC toan HPGL Compatible Printer 4 23 Step 1 Store the HPGL initialization sequence lislessses eese 4 23 Step 2 Store the exit HPGL mode and form feed sequence 2 00a eee eee 4 24 Step 3 Send the HPGL initialization sequence to the printer Lus 4 24 Step 4 Send the plot file to the printer i isisso aso ah Rar RE RR 4 24 Step 5 Send the exit HPGL mode and form feed sequence to the printer 4 24 Outputting Single Page Plots Using a Printer 0 000 cece eee 4 24 Outputting Multiple Plots to a SinglePageUsinga Printer 0 00 00a 4 25 Plotting Multiple Measurements Per Page from Disk 0020 cece eee eee 4 26 To Plot Multiple Measurements on a Full Page 2 0 c cece eee 4 27 To Plot Measurements in Page QuadrantsS
20. 23 To find the 1 dB compression point on channel 1 press Marker Search SEARCH MAX MKR ZERO Marker Search SEARCH TARGET Notice that the marker on channel 2 tracked the marker on channel 1 24 Press MKR MODE MENU MARKERS UNCOUPLED 25 Totake the channel 2 marker out of the A mode sothat it reads the absolute output power of the amplifier in dBm press AMODE MENU AMODE OFF Figure 1 50 Gain Compression Using Power Sweep CHi S2i log MAG 2 dB REF 19 81 dB 1 9956 dB 1 dB Gain fomredsion 2 dBm AREF 4 PRm C CH2 B log MAG 5 dB REF dB 1 7 6474 dB START 25 dBm CW 1 466 anao MHz STOP 4 0 dBm 1 62 Making Measurements Measuring Amplifiers Measuring Gain and Reverse Isolation Simultaneously Since an amplifier will have high gain in the forward direction and high isolation in the reverse direction the gain S23 will be much greater than the reverse isolation Sj Therefore the power you apply tothe input of the amplifier for the forward measurement S21 should be considerably lower than the power you apply to the output for the reverse measurement S12 By applying low power in the forward direction you ll prevent the amplifier from being saturated A higher power in the reverse direction keeps noise from being a factor in the measurement and accounts for any losses caused by attenuators or couplers on the amplifi
21. For 4 Response Or LLLLLLLI pa581e 6 20 Calibrating for Increased Measurement Accuracy Frequency Response and Isolation Error Corrections 8 To measure the standard press SHORT or OPEN If the calibration kit you selected has a choice between male and female calibration standards remember to select the sex that applies tothe test port and not the standard The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the softkey that you selected after it finishes the measurement and computes the error coefficients 9 Connect the load calibration standard to the test port 10 To measure the standard for the isolation portion of the correction press ISOL N STD a Press AVERAGING ON AVERAGING FACTOR and enter at least four times more averages than desired during the device measurement 11 To compute the response and directivity error coefficients press DONE RESP ISOL N CAL The analyzer displays the corrected S44 or S22 data The analyzer also shows the notation Cor to the left of the screen indicating that the correction is switched on for this channel NOTE You can save or storethe error correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving M easurement Results for procedures 12 This completes the response and isolation error correction for reflection measurements You can connect and measure your de
22. ISOLATION m You could choose not to perform the isolation measurement by pressing OMIT ISOLATION DONE TRL LRM 6 58 NOTE Calibrating for Increased Measurement Accuracy LRM Error Correction You should perform the isolation measurement when the highest dynamic range is desired To perform the best isolation measurements you should reduce the system bandwidth or activate the averaging function A poorly measured isolation class can actually degrade the overall measurement performance If you are in doubt of the isolation measurement quality you should omit the isolation portion of this procedure 14 You may repeat any of the previous steps There is no requirement to go in the order of steps When the analyzer detects that you have made all the necessary measurements the message line will show PRESS DONE IF FINISHED WITH CAL Press DONE TRL LRM The message COMPUTING CAL COEFFICIENTS Will appear indicating that the analyzer is performing the numerical calculations of error coefficients NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures 15 Connect the device under test The device S parameters are now being measured NOTE When making measurements using the same port with uncoupled channels the power level for each channel must fall within the
23. 3 20 Making Time Domain Measurements Time Domain Low Pass Mode Figure 3 16 Transmission Measurements Using Low Pass Impulse Mode CH4 A R Re 50 mu REF OU CH8 B R Re 50 mu REF OU CER 4 M m EREA START 1 ns STOP 1 ns a Comparing Transmission Paths through a Power Divider THRU LINE FIBER OPTIC CABLE CH1 B A lin MAG 200 mu REF 500 mu Lou INPUT PULSE MMF E os Sk 5 dis ns TARGE r VALUE NO ent 10 p cor m Hic CH1 CENTER O s SPAN 10 ns CH2 B A lin MAG 100 mU REF 200 mu ou outeur PUL E MMA b Cor Hig L CH2 CENTER 7 883 us SPAN 10 ns b Measuring Pulse Dispersion on a 1 5 km Fiber Optic Cable pg6195 c 3 21 Making Time Domain Measurements Transforming CW Time Measurements into the Frequency Domain Transforming CW Time Measurements into the Frequency Domain Theanalyzer can display the amplitude and phase of CW signals versus time For example use this mode for measurements such as amplifier gain as a function of warmup time i e drift The analyzer can display the measured parameter e g amplifier gain for periods of up to 24 hours and then output the data to a digital plotter for hardcopy results These strip chart plots are actually measurements as a function of time timeis the independent variable and the horizontal display axis is scaled in time units
24. India 1 600 11 2929 000 800 650 1101 8 3 Safety and Regulatory Information Safety Symbols Safety Symbols The following safety symbols are used throughout this manual Familiarize yourself with each of the symbols and its meaning before operating this instrument CAUTION WARNING Caution denotes a hazard It calls attention to a procedure that if not correctly performed or adhered to would result in damageto or destruction of theinstrument Do not proceed beyond a caution note until the indicated conditions are fully understood and met Warning denotes a hazard It calls attention to a procedure which if not correctly performed or adhered to could result in injury or loss of life Do not proceed beyond a warning note until the indicated conditions are fully understood and met Instrument Markings A N10149 ICES NMB 001 8 4 The instruction documentation symbol The product is marked with this symbol when it is necessary for the user to refer to the instructions in the documentati on TheCE mark is a registered trademark of the European Community If accompanied by a year it is when the design was proven The CSA mark is a registered trademark of the Canadian Standards Association This is a symbol of an Industrial Scientific and Medical Group 1 Class A product The C Tick mark is a registered trademark of the Australian Spectrum Management Agency This is a marking to in
25. Measuring Electrical Length and Phase Distortion on page 1 43 Electrical Length Phase Distortion deviation from linear phase group delay Characterizing a Duplexer Measuring Amplifiers on page 1 53 Measuring Harmonics Option 002 Only Measuring Gain Compression Measuring Gain Compression and Reverse Isolation Simultaneously Making High Power M easurements Using the Swept List Mode to Test a Device on page 1 65 Using Limit Lines to Test a Device on page 1 71 Using Test Sequencing to Test a Device on page 1 113 The following chapters describe how to use more instrument functions as indicated by their chapter titles 1 2 Chapter 4 Printing Plotting and Saving M easurement Results Chapter 5 Optimizing Measurement Results Chapter 6 Calibrating for Increased Measurement Accuracy Making Measurements More Instrument Functions Not Described in This Guide More Instrument Functions Not Described in This Guide Tolearn about instrument functions not covered in this user s guide refer tothe following chapters in the reference guide Menu Maps contains maps of the instrument menu structure Hardkey Softkey Reference contains descriptions of all instrument functions 1 3 Making Measurements Making a Basic Measurement Making a Basic Measurement There are five basic steps when you are making a measurement 1 Connect the device under test and any required test equip
26. NOTE The preset state of the instrument can be configured sothat interpolated error correction is on or off Press CONFIGURE MENU USER SETTINGS PRESET SETTINGS CAL INTERP ON off toconfigure the preset state of interpolated error correction System performance is unspecified when using interpolated error correction The quality of the interpolated error correction is dependent on the amount of phase shift and the amplitude change between measurement points If phase shift is no greater than 180 per approximately five measurement points interpolated error correction offers a great improvement over uncorrected measurements The accuracy of interpolated error correction improves as the phase shift and amplitude change between adjacent points decrease When you use the analyzer in linear frequency sweep perform the original calibration with at least 30 points per 1 GHz of frequency span for greatest accuracy with interpolated error correction Interpolated error correction is available in three sweep modes linear frequency power sweep and CW time NOTE If thereis a valid correction array for a linear frequency sweep this may be interpolated to provide correction at the CW frequency used in power sweep or CW time modes This correction is part of the interpolated error correcti on feature Error Correction Stimulus State Error correction is only valid for a specific stimulus state which you must select before you start a correction If yo
27. PL00001 FP Torun the sequence press SEQUENCE 1 SEQ 1 Limit Test Example Sequence This measurement example shows you how to create a sequence that will branch the sequence according to the outcome of a limit test Refer to Using Limit Lines to Test a Device on page 1 71 for a procedure that shows you how to create a limit test For this example you must have already saved the following in register 1 device measurement parameters aseries of active visible limit lines anactivelimit test 1 To create a sequence that will recall the desired instrument state perform a limit test and branch to another sequence positi on based on the outcome of that limit test press NEW SEQ MODIFY SEQUENCE 1SEQ1 RECALL KEYS RECALLKEYS MENU RECALL REGI SPECIAL FUNCTIONS DECISION MAKING IF LIMIT TEST PASS SEQUENCE 2 SEQ2 IF LIMIT TEST FAIL SEQUENCE 3SEQ3 DONE SEQ MODIFY This will create a displayed list for sequence 1 as shown Start of Sequence RECALL REG 1 F LIMIT TEST PASS THEN DO SEQUENCE F LIMIT SEQUENCE EST FAIL THEN DO WOHN 2 Tocreate a sequence that stores the measurement data for a device that has passed the limit test press NEW SEQ MODIFY SEQUENCE 2SEQ2 SELECT DISK INTERNAL DISK RETURN DEFINE DISK SAVE DATAARRAYON RETURN SAVE STATE DONE SEQ MODIFY 1 117 Making Measurements Using Test Sequencing to Test a Device This will create a displayed
28. TUNED RECEIVER EDIT LIST ADD CW FREQ 100M u NUMBER OF POINTS 26x1 DONE DONE LIST FREQ B TITLE POW LEV 6DBM PERIPHERAL HPIB ADDR 19x1 TITLE TO PERIPHERAL TITLE FREQ MODE CW CW 100MHZ TITLE TO PERIPHERAL CALIBRATE RESPONSE CAL STANDARD DONE CAL CLASS TITLE CONNECT MIXER PAUSE LOOP COUNTER 26x1 SCALE DIV 2 x1 REFERENCE POSITION 0 x1 REFERENCE VALUE 2 0x1 MANUAL TRG ON POINT TITLE FREQ MODE CW CW 500MHZ FREQ CW STEP 100MHZ TITLE TO PERIPHERAL TITLE POW LEV 13DBM PERIPHERAL HPIB ADDR 21x1 TITLE TO PERIPHERAL 2 28 Making Mixer Measurements Fixed IF Mixer Measurements MODE CW CW 600MHZ FREQ CW STEP 100MHZ LE TO PERIPHERAL DO SEQUENCE SEQUENCE 2 nj zy H ww IO pP Sequence 2 Setup The following sequence makes a series of measurements until all 26 CW measurements are made and the loop counter value is equal to zero This sequence includes taking data incrementing the source frequencies decrementing the loop counter e labeling the screen 1 Press the following keys on the analyzer to create sequence 2 NOTE To enter the following sequence commands that require titling an external keyboard may be used for convenience DONE SEQ MODIFY NEW SEQ MODIFY SEQ SEQUENCE 2SEQ2 Taking Data SPECIAL FUNCTIONS WAIT x TRIGGER MENU MANUAL
29. When calibrating a network analyzer the actual calibration standards must have known physical characteristics For the reflect standard these characteristics indudethe offset in electrical delay seconds and theloss ohms second of delay The characteristic impedance OFFSET ZO is not used in the calculations in that it is determined by the line standard The reflection coefficient magnitude should optimally be 1 0 but need not be known since the same reflection coefficient magnitude must be applied to both ports Thethru standard may be a zero length or known length of transmission line The value of length must be converted to electrical delay just like that done for the reflect standard Theloss term must also be specifi ed 7 72 Operating Concepts TRL LRM Calibration Theline standard must meet specific frequency related criteria in conjunction with the length used by thethru standard In particular the insertion phase of the line must not be the same as the thru The optimal line length is 1 4 wavelength 90 degrees relative to a zero length thru at the center frequency of interest and between 20 and 160 degrees of phase difference over the frequency range of interest Note these phase values can be N x 180 degrees where N is an integer If two lines are used LRL the difference in electrical length of the two lines should meet these optimal conditions M easurement uncertainty will increase significantly when the inserti
30. lt esc gt amp a0L no left margin a zero capital L esc amp a400M noright margin a 4 zero zero capital m esc amp loE no top margin lower case 1 zero capital E lt esc gt c7680x5650Y frame size 10 66 x 7 847 720 decipoints inch lt esc gt p50x50Y move cursor to anchor point lt esc gt cOT set picture frame anchor point lt esc gt r 3U set CMY palette lt esc gt 1B enter HPGL mode cursor at PCL NOTE As shown in Table 4 7 the lt esc gt is the symbol used for the escape character decimal value 27 4 23 Printing Plotting and Saving Measurement Results Outputting Single Page Plots Using a Printer Step 2 Store the exit HPGL mode and form feed sequence 1 Create a test file by typing in each character as shown in the left column of Table 4 8 Do not insert spaces or linefeeds 2 Namethefile exithpgl Table 4 8 HPGL Test File Commands Command Remark lt esc gt 0A exit HPGL mode lt esc gt E form feed Step 3 Send the HPGL initialization sequence to the printer Type print hpglinit tosend the initialization sequence to the printer Step 4 Send the plot file to the printer Type print filename where filename is the name of the HPGL plot file to send the plot file to the printer Step 5 Send the exit HPGL mode and form feed sequence to the printer Type print exithpgl tosend the HPGL mode and form feed sequence to the printer Outputting Single Page Plots Using a
31. 1 22 modified 1 23 modify colors menu 1 22 command deleting 1 99 inserting 1 100 modifying 1 100 commands that require dean sweep 1 105 commands that sequencing completes before next command 1 104 Index 2 comma separated values See CSV format compensating for directional coupler response 6 35 compliance with German noise requirements 8 8 computer what you can save 4 35 confidence check 6 67 configuring plot function 4 9 configuring two sources 2 27 connecting device under test 1 4 required test equipment 1 4 connector care 5 3 repeatability 5 4 continuous correction mode using 6 38 continuous markers 1 24 conversion 7 9 conversion compression using frequency offset mode 2 37 conversion loss 2 18 conversion loss using frequency offset mode 2 11 conversion menu 7 22 copy mode 7 79 correction sampler IF 7 7 coupling display markers 1 31 coupling power between channels land 2 1 58 7 88 coupling channel stimulus 7 14 creating flat limit lines 1 72 sequence 1 97 sloping limit line 1 74 user defined TRL calibration kit 6 52 user defined TRM calibration kit 6 56 creating single point limits 1 76 crosstalk 7 40 CSV format saving measurement results in 4 43 CW frequency range in external source mode 7 85 CW frequency setting 1 38 CW time measurements 3 22 CW time sweep 7 19 D data formats ASCII 4 40 data processing 7 6 processing details 7 7 data trace 1 19
32. 4 4 ad bea xxda bead obs sed ded oe tees whee wes e ide 1 76 Editing Limit SAIS oed eEbR ES ER NI HERERERIEEYAOKFKERE RE ERI ERE RT E REPE 1 77 RUMO a Limit Test arro rrer eTA EERE pees PEReOwISE RE oi 1 77 OSE CNG LE LINES saa c Ree PER CERDOE DER EORCHERA Pa CICER EU dead ewe andes 1 79 Using Ripple Limits to Test a Device 1 ieee 1 80 Setting Up the List or Ripple Limits to Test s sath cieeeees RESP diet hier ieaws d ERA 1 80 Editing Ripple Test LWIMS a aao rerPEXVPRSQEPRE34q RA IIQUPPEA4 oar RUPTA Rid doy nese 1 83 RUNNING te Ripple Test icractquexdmds awed nee keds Rd be Ree Ee R OR on POR 1 85 Using Bandwidth Limits to Test a Bandpass Filter 0000 c eee eee 1 91 Seting Up Banmel dtr LIMIS vualiebedAa REPRE ERI EIN REIXAE P HREPa T iat anaes 1 91 Runmngs Bandwidth Test aaa teuer d eR E WEEXAR dE pee TPRXe derkdweeeEprisqea pu 1 93 Using Test Seguencd ccexexekes b d i bei PRG DE PS RARE ewe DOERR A E PREGA 1 97 Haw COU Se Test Sequere uade educa canoe ARR 9 eee EI XC e dE C el ahd BE 1 97 Creating a Sede uiicar reb PRERERGSDA E RIICOMERERRES PI HER sd E GRE Ea dd 1 97 RUG a SUIS uou ka xraxetepqereseesqegsaednasqePPEpp dxxstererebe pep 1 99 SLODDIng 6 SeDUBIICEE osa iqerduorebx3xdendbrotesiedadpbcisbeddq4qieteadokdqrbaog e donsdR 1 99 Edrnaga SSeS up deg ce debe apad oe ded apa DISS ode GI did ac bee de dod eds 1 99 Clearing a Sequence from Memory 05 0 cece eee e nene 1 101 Changing he Sequence Tile xc ced e
33. 7 29 print aborting a process 4 31 print function configuring 4 4 defining 4 6 printer color printer using 4 6 HPGL compatible printer 4 19 4 23 HPGL 2 compatible printer 4 9 printing measurement results 4 3 multiple measurements per page 4 8 one measurement per page 4 7 parameters resetting to default values 4 7 sequence 1 104 solving problems 4 33 printing or plotting thelist values or operating parameters 4 32 entire list of values 4 32 single page of values 4 32 procedure TRL calibration 7 71 procedures for error correcting measurements 6 10 types of error correction 6 10 processing details 7 7 accuracy enhancement 7 8 Index ADC 7 7 conversion 7 9 display memory 7 9 elecrical delay block 7 8 format 7 9 format arrays 7 9 gating 7 8 IF detection 7 7 pre raw data arrays 7 8 ratio calculations 7 7 raw arrays 7 8 sampler IF correction 7 7 scale and offset 7 9 smoothing 7 9 Sweep to sweep averaging 7 8 trace math operation 7 8 transform 7 9 vector error correction 7 8 processing data 7 6 prompting user to connect mixer test setup 2 26 purging a sequence from a disk 1 103 R range 3 30 forward transform 3 24 frequency 1 58 resolution 3 34 ratio calculations 7 7 ratio measurements in channel 1 and 2 to 1 20 raw arrays 7 8 raw source match 7 70 real format 7 29 recall time reducing 5 17 recalling a file 4 52 s
34. DONE LIMIT TYPE SINGLE POINT RETURN Figure 1 58 Example Flat Limit Lines CHL S2 log MAG 10 dE REF 50 dB tp CENTER 134 808 8880 MHz SPAN 58 884 888 MHz aw000011 Creating a Sloping Limit Line This example procedure shows you how to make limits that test the shape factor of a SAW filter The following limits are set Frequency Range Power Range 123 MHz to 125 MHz 65 dB to 26 dB 144 MHzto 146 MHz 26 dB to 65 dB 1 74 Making Measurements Using Limit Lines to Test a Device 1 To access the limits menu and activate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE CLEARLIST YES 2 Toestablish the start frequency and limits for a sloping limit linethat tests thelow side of the filter press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SLOPING LINE RETURN 3 Toterminate the lines and create a sloping limit line press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SINGLE POINT RETURN 4 To establish the start frequency and limits for a sloping limit line that tests the high side of the filter press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SLOPING LINE RETURN 5 Toterminatethe lines and create a sloping limit line press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SINGLE POINT RETURN You could usethis type of limit to test the shape factor of
35. During measurement calibration the analyzer measures actual well defined standards and mathematically compares the results with ideal models of those standards The differences are separated into error terms which arelater removed during error correction Most of the differences are due to systematic errors repeatable errors introduced by the analyzer test set and cables which are correctable The standard devices required for system calibration are available in compatible calibration kits with different connector types Each kit contains at least one short circuit one open circuit and an impedance matched load In kits that require adapters for interface to the test set ports the adapters are phase matched for calibration prior to measurement of non insertable and non reversible devices Other standard devices can be used by specifying their characteristics in a user defined kit as described in Modifying Calibration Kits on page 7 56 The accuracy improvement of the correction is limited by the quality of the standard devices and by the connection techniques used For maximum accuracy ensure that the connectors are clean and use a torque wrench for final connections Electronic calibration ECal modules serve as the calibration standards for electronic calibration procedures ECal modules are electronic networks that simulate impedance states that are similar to mechanical standards The factory error correction for optimum perfor
36. Figure 7 45 Typical Measurement Set up NETWORK ANALYZER hs 0000 0000 o 9g BIAS TEE BIAS TEE oOo 2 10 dB 10 dB ATTENUATOR FIXTURE ATTENUATOR pg640e If the device measurement requires bias it will be necessary to add external bias tees between the fixed attenuators and the fixture The internal bias tees of the analyzer will not pass the bias properly through the external fixed attenuators Be sureto calibrate with the external bias tees in place no bias applied during calibration to remove their effect from the measurement Becausethe bias tees must be placed after the attenuators they essentially become part of the fixture Their mismatch effects are the same for source match and load match sothe TRL CAL routine will correct for their effects Although the fixed attenuators improve the raw mismatch of the network analyzer system they also degrade the overall measurement dynamic range This effective mismatch of the system after calibration has the biggest effect on reflection measurements of highly reflective devices Likewise for well matched devices the effects of mismatch are negligible This can be shown by the following approximation Reflection magnitude uncertainty Ep EgS4 Es S11 E 521512 7 70 Operating Concepts TRL LRM Calibration Transmission magnitude uncertainty Ex E7S21 Es511521
37. Iterate between marker 1 and marker 2 by pressing MARKER 1 and MARKER 2 respectively and turning the front panel knob or entering values from the front panel keypad to position the markers around the center frequency When finished positioning the markers make sure that marker 2 is selected as the active marker NOTE Step 2 can also be performed using MKR ZERO and MARKER 1 However when usingthis method it will not be possibletoiterate between marker zero and marker 1 3 Press MARKER SPAN to change the frequency span to the range between marker 1 and marker 2 1 36 Making Measurements Using Markers Figure 1 25 Example of Setting the Frequency Span Using Marker CHL S2 iog MAG 20 dB REF 68 dB 2 10 257 dB CH1 S2 log MAG 20 dB REF 60 dB 2 7 5675 dB 1 63 655 ait MHz 63 955 eli MHz AREF 1 i REF 1 L ij 8 dB 1 ot dB Hz B Hz MARKER 2 FUE 0550 1 MHz i CENTER 134 888 828 MHz SPAN 176 427 202 MHz CENTER 133 558 933 MHz SPAN 63 055 11 MHz pg6231 Setting the Display Reference Value 1 Press and turn the front panel knob or enter a value from the front panel keypad to position the marker at the value that you want for the analyzer display reference value 2 Press MARKER REFERENCE to changethe reference value to the value of the active marker Figure 1 26 Ex
38. The data is shown on the display as a single trace that is a composite of all data taken The trace may appear uneven because of the distribution of the data points but the frequency scale is linear across the total range Oncethelist frequencies have been defined or modified the list frequency sweep mode can be selected with the LIST FREQ SWEPT softkey in the sweep type menu The frequency list parameters can also be saved with an instrument state Setting Segment Power To enable the SEGMENT POWER function you must first select LIST POWER ON off in the edit subsweep menu List power is off by default and theasterisks that appear in the power column of thelist table indicate that power for the sweep is being set by the normal analyzer power controls The power settings for all segments are restricted to a single power range This prevents the attenuator from switching to different settings mid sweep Select the power range and then edit the list table to specify the segment powers If the power range is selected after thelist has been defined the list settings may be affected When analyzer port power is uncoupled the segment power level can be set independently for each port To dothis you must first select a measurement parameter to activate the port whose power you want to set For example select S11 to set port 1 power or S22 to set port 2 power Notice that the list modetable will only display the currently selected port in t
39. Therefore sinceit is the analyzer receiver that controls the source it is only necessary to set the start and stop frequencies from the receiver LO Frequency Accuracy and Stability The analyzer source is phaselocked to its receiver through a reference loop n the frequency offset mode the mixer under test is inserted in this loop To ensure that the analyzer phaselocks correctly it is important that you use an LO source that has frequency accuracy better than 1 MHz and residual FM 20 kHz RMS Power Meter Calibration Mixer transmission measurements are generally configured as follows measured output power Watts set input power Watts OR measured output power dBm set input power dBm For this reason the set input power must be accurately controlled in order to ensure measurement accuracy The amplitude variation of the analyzer is specified at 1 dB over any given source frequency This may give a maximum 2 dB error for a mixer transmission test setup 1 dB for the source over the IF range during measurement and 1 dB over the RF range during measurement 2 10 Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode Higher measurement accuracy may be obtained through the use of power meter calibration You can use power meter calibration to correct for power offsets losses and flatness variations occurring between the analyzer source and theinput to the mixer under test Refer to the power m
40. They represent the raw data and format arrays You can save your measurement data in any or all of these format arrays each time the data is saved Select the arrays of interest based on the factors discussed in this section For this discussion only DISK saves will be described Data can be saved to internal non volatile memory or transferred over GPIB as well as toa floppy disk You will find multiple files saved depending on the arrays chosen under the analyzer s DEFINE DISK SAVE menu When using these files it is important to know which file extension is needed for your particular job 4 49 Printing Plotting and Saving Measurement Results Saving Measurement Results Raw Arrays On the analyzer press the Save Recall DEFINE DISK SAVE RAW ARRAY ON Data created the first timein this manner will be saved as filename FILEOO r1 Thefile extension r1 indicates the data was created while channel 1 was active and stored in the analyzer s raw data array If you savethe data again but while channel 2 is active you will get a new file called FILEOI r2 RAW data are not commonly used unless sophisticated data processing is to be performed in an external PC As an example multi port calibration is created by exporting raw data to a PC where error correction for each of the multi port paths is applied to them Data Arrays Press Save Recall DEFINE DISK SAVE DATA ARRAY ON Data created the first time in this manner will be sav
41. This menu allows you to define the input ports for power ratio measurements or a single input for magnitude only measurements of absolute power You cannot use single inputs for phase or group delay measurements or any measurements with averaging activated 7 23 Operating Concepts Analyzer Display Formats Analyzer Display Formats The key accesses the format menu This menu allows you to select the appropriate display format for the measured data The analyzer automatically changes the units of measurement to correspond with the displayed format Special marker menus are available for the polar and Smith formats each providing several different marker types for readout of values The selected display format of a particular S parameter or input is assigned to that parameter Thus if different S parameters are measured even if only one channel is used each parameter is shown in its selected format each time it is displayed Thefollowing illustrations show a reflection measurement of a bandpass filter displayed in each of the available formats Log Magnitude Format The LOG MAG softkey displays the log magnitude format This is the standard Cartesian format used to display magnitude only measurements of insertion loss return loss or absolute power in dB versus frequency The bandpass filter reflection data in a log magnitude format is illustrated in Figure 7 6 Figure 7 6 Log Magnitude Format CHi 11 log MAG 5 dB REF 2
42. V Standing wave ratio SWR is defined as the ratio of maximum standing wave voltage to the minimum standing wave voltage and can be derived from the reflection coefficient T using the following equation Return loss can be derived from the reflection coefficient as well V rT V SWR 1 I 1 r Return loss 20 log I NOTE Mixers are three port devices and the reflection from any one port depends on the conditions of the other two ports You should replicate the operating conditions the mixer will experience as dosely as possible for the measurement For all mixer SWR measurements use the same power level that the mixer will use during normal operation When you measure the RF port SWR you should havethe LO drive level present and set tothe expected frequency and power levels Different LO drives and frequencies may yield different values for SWR at the same RF frequencies The IF port should be terminated in a condition as close to its operating state as possible The measurements of LO port SWR and IF port SWR are very similar For IF port SWR you should terminate the RF port in a matched condition and apply the LO signal at its normal operating level For the LO port SWR theRF and IF ports should both be terminated in conditions similar to what will be present during normal operation 2 48 3 Making Time Domain Measurements 3 1 Making Time Domain Measurements Using This Chapter Using T
43. calibration only and Figure 7 41b shows the same measurement with an S11 one port calibration Figure 7 40 Response versus S11 1 Port Calibration on Log Magnitude Format CH1 S11 log MAG 1 dB REF O dB CHi S11 log MAG 1 dB REF O dB REFLEET ION RESPONSE CALIBRATION 511 1 PORT CALIBRATION T i 4 START 300 DOD MHz STOP 3 ODO 000 O00 MHz START 300 ODD MHz STOP 3 900 000 O00 MHz pg6166d a b Figure 7 41 Response versus S4 1 Port Calibration on Smith Chart y SIT iu FS CH1 S11 1u FS 11 1 PORT CALIBR REFLECTION RESPONS Cor START 300 000 MHz STOP 3 000 000 O00 MHz START 300 O00 MHz STOP 3 900 000 000 MHz pg6167 c 7 52 Operating Concepts Measurement Calibration Theresponse of a device in a log magnitude format is shown in Figure 7 42 Figure 7 42a shows the response using a response calibration and Figure 7 42b the response using a full two port calibration Figure 7 42 Response versus Full Two Port Calibration CHI 21 log MAG 1 dB REF 20 d8 CHI 51 log MAG 1 dB REF 20 dB hp TRANSMISSION RESPONSE CALIBRATION hp FULL 2 PORT CALIBRATION LL Ld LLLI LI LET START 300 000 MHz STOP 3 000 000 MHz START 300 00 MHz STOP 5 000 000 MHz a b 09681d 7 53 Operating C
44. e won door Ped ee dob oca 4 4 DENMAN FUNCION iucpserckite vs qx CERE RE SqEDKIFESD NX TREE RHERE ERR APER TS 4 6 IT You Are mnga Cola Prints uesaszsacecteperbbeepbrybexoq aiia qu pEXageerkqt qge4s 4 6 To Reset the Printing Parameters to Default Values 0 0 cece eee 4 7 Printing One Measurement Per Page 00 cece eee eee 4 7 Printing Multiple Measurements Per Page 000 0c eee eee eee 4 8 Conmigo a Fit Pun iuge se pprRa 3k Rab x cL ECEPPSI RPERQPPRCCERCPOP goers 4 9 If You Are Plotting to an HPGL 2 Compatible Printer leslllees eres 4 9 IT You Are Platting toa Pen Plotte Liosecosdadeakesevateyixtbyd4due be ddadid gs 4 10 If You Are Plotting Measurement Results to a Disk Drive lllslslsessse 4 11 Denning a PIE PUN aesdcudcooex feq epidpETegAqqdg E howd 44RD WEL ER REC HS BS 4 13 Choosing Display EIGmnts isered bteteleireeREbe 2igergd bk RR dX o PARERE ER Cop RR 4 13 Soler ang d MLO FOR sci bue ww ERA Ead ed ERR ES v bip acoso PREC o pale dear 4 13 Selec ng Pen Numbers and COGS iispsakas dao ERA ER3EPTERETIdAEREPTIYSId ERR 4 14 DCLG LINE T VOSS Lua xxr sso OSr EES S46 o 9S RL OQ er xa dap Pack ddp pde 4 15 CHOOSING Scale os kaa ue e sapien EORR ER SEERE ENE E Pe Puce be EO OP dod 4 15 C oos ClO SEE cia pypaquasdace CURE dE PIE Ed Pues d Vd bd tagsd anii 4 16 To Reset the Plotting Parameters to Default Values 0 00 ccc es 4 16 Plotting One Measurement Per Page Using a Pen Plotter
45. following manner e ftheripple test passes the ripple limits are drawn on the display for each frequency band Within each frequency band an upper and lower ripple limit is drawn such that they are equidistant above the upper point of the measured trace and below the lower point of the measured trace 1 86 Making Measurements Using Ripple Limits to Test a Device e ftherippletest fails the ripple limits are drawn on the display for each frequency band Within each frequency band thelower ripple limit is drawn at thelowest point on the measured trace and the upper ripple limit is drawn at the user specified maximum ripple value abovethe lower ripple limit The ripplethat exceeds the maximum ripple value extends above the upper limit This measured trace that extends above the upper limit is displayed in red Figure 1 66 shows the filter pass band tested with the ripple limits activated Notice that there arethree sets of ripplelimits shown Also notice that the measured trace exceeds the upper ripple limit only in Frequency Band 3 Figure 1 66 Filter Pass Band with Ripple Test and Ripple Limits Activated i Jun 2888 18 25 22 Hi 11 Lac 1i dB REF 3 dB Frequency Frequency RIPL1 FAIL Band 2 Band 1 Frequency Band 3 LL START 100 000 966 GHz STOP 3 568 000 000 GHz pa5199e Changing the Ripple Limits Line Color The color of the lines that r
46. frequency response 7 40 isolation 7 40 load match 7 39 measurement errors directivity 7 38 source match 7 39 measurement parameters 1 67 6 4 center frequency setting 1 35 choosing 1 4 display reference value setting 1 37 electrical delay setting 1 37 for IF range 2 18 frequency span setting 1 36 lower stopband parameters 1 67 Index markers setting with 1 34 passband parameters 1 67 start frequency setting 1 34 stop frequency setting 1 35 upper stopband parameters 68 measurements basic 1 4 phase or group delay 2 32 measuring device under test 1 5 gain and reverse isolation simultaneously 1 63 insertion phase response 1 7 1 8 separate transmission paths through the test device using low pass impulse mode 3 20 small signal transient response using low pass step 3 19 measuring amplifiers 1 53 harmonic operation understanding 1 57 harmonics measuring 1 54 measuring gain and reverse isolation simultaneously 1 63 measuring gain compression 1 59 measuring electrical length 1 43 measuring gain compression 1 59 linear sweep 1 61 using linear sweep 1 61 measuring harmonics 1 54 additional harmonic measurements 1 56 making harmonic measurements 1 55 measuring magnitude 1 7 magnitude response 1 7 measuring phase distortion 1 43 1 45 deviation from linear phase 1 46 group delay 1 46 memory math functions 1 19 memory trace 1 19 1 20 viewing 1 20 memory d
47. http www icmicrowave com 6 50 Calibrating for Increased Measurement Accuracy Making Non Coaxial Measurements If You Want to Design Your Own Fixture Ideally a fixture should provide a transparent connection between the test instrument and the test device This means it should have no loss or electrical length and a flat frequency response to prevent distortion of the actual signal A perfect match to both the instrument and the test device eliminates reflected test signals The signal should be effectively coupled into the test device rather than leaking around the device and resulting in crosstalk from input to output Repeatable connections are necessary to ensure consistent data Realistically it is impossible to build an ideal fixture especially at high frequencies However it is possible to optimize the performance of the test fixture relative to the performance of the test device If the fixture s effects on the test signal are relatively small compared to the device s parameters then the fixture s effects can be assumed to be negligible For example if the fixture s loss is much less than the acceptabl e measurement uncertainty at the test frequency then it can be ignored For additional information about fixtures refer to Agilent Technologies Application Note 1287 9 n Fixture Measurements Using Vector Network Analyzers literature number 5968 5329E 6 51 Calibrating for Increased Measurement Accuracy Calibr
48. important that you accurately set the power level at either the device input or output The analyzer is capable of using an external GPIB power meter and controlling source power directly Refer to Chapter 6 Calibrating for Increased Measurement Accuracy for information on power meter calibration This section contains the following measurement examples Measuring Harmonics Option 002 on page 1 54 Measuring Gain Compression on page 1 59 Measuring Gain and Reverse Isolation Simultaneously 1 53 Making Measurements Measuring Amplifiers Measuring Harmonics Option 002 The analyzer has the capability of measuring swept second and third harmonics as a function of frequency in a real time manner By using trace math the second third harmonic response can be displayed directly in dBc dB below the fundamental or carrier The ability to display harmonic level versus frequency or RF power allows real ti me tuning of harmonic distortion Figure 1 43 Absolute Fundamental 2nd and 3rd Harmonic Output Levels 21 Jun 1994 12 41 19 CH1 B amp M log MAG 18 dB REF dB 1 25 744 dB CH2 B log MAG 18 dB REF dB l1 51 569 dB spa 500 hoa ada MHz n Fundamental Cor P I H 2 or oP ee 2nd Hamonic PRm Cor FS 1 Sh 3rd Hamonic H 3 START START CH1 B M CH2 B M hp PRm H 3
49. limit lower limit and limit type The ending stimulus value is the start value of the next segment or a segment can be terminated with a single point segment You can enter limit values as upper and lower limits or delta limits and middle value As new limit segments are defined the tabular listing is updated If limit lines are switched on they are shown on the display If no limits have been defined the table of limit values shows the notation EMPTY Limit segments are added to the table using the ADD softkey or edited with the EDIT softkey as previously described The last segment on the list is followed by the notation END Edit Segment Menu This menu sets the values of the individual limit segments The segment to be modified or a default segment is selected in the edit limits menu The stimulus value can be set with the controls in the entry block or with a marker the marker is activated automatically when this menu is presented Thelimit values can be defined as upper and lower li mits or delta limits and middle value Both an upper limit and a lower limit or delta limits must be defined if only onelimit is required for a particular measurement force the other out of range for example 4500 dB or 500 dB As new values are entered the tabular listing of limit values is updated Segments do not have to be listed in any particular order the analyzer sorts them automatically in increasing order of start stimulus val
50. range that can be used for each value of n for low pass time domain measurements Reflection Measurements in Time Domain Low Pass Figure 3 12 shows the time domain response of an unterminated cable in both the low pass step and low pass impulse modes Figure 3 12 Time Domain Low Pass Measurements of an Unterminated Cable CHi S44 Re 200 mU AEF 400 mu CH1 START O s STOP 40 ns CH1 START O s STOP 40 ns pg6197 c Interpreting the Low Pass Response Horizontal Axis The low pass measurement horizontal axis is the two way travel time to the discontinuity as in the bandpass mode The marker displays both the two way time and the electrical length along the trace To determine the actual physical length enter the appropriate velocity factor as described in Time Domain Bandpass Mode on page 3 12 3 16 Making Time Domain Measurements Time Domain Low Pass Mode Interpreting the Low Pass Response Vertical Axis The vertical axis depends on the chosen format In the low pass mode the frequency domain data is taken at harmonically related frequencies and extrapolated to dc Because this results in theinverse Fourier transform having only a real part the imaginary part is zero the most useful low pass step mode format in this application is the real format It displays the response in reflection coefficient units This mode is similar to the tradition
51. saving to display memory 1 19 decision making functions 1 111 decoupled channel power 1 13 stimulus 1 13 decreasing frequency span 5 10 sweep rate 5 8 time delay 5 8 decrementing the loop counter 2 29 default colors 1 22 defining plot function 4 13 print function 4 6 defining a print function color printer using 4 6 resetting print parameters to default value 4 7 delay block electrical 7 8 delay determining electrical 6 75 delay electrical 7 33 delay group 1 46 2 32 deleting commands 1 99 frequency signals 6 35 line segments 1 77 deleting a file 4 51 all files 4 51 instrument state file 4 51 delta markers 1 28 demodulating the results of the forward transform 3 23 designing your own fixture 6 51 detecting IF delay 5 10 detection IF 7 7 deviation from linear phase 1 46 device measurement 7 45 device measurements 6 4 device under test measuring 1 5 device under test connecting 1 4 device bilateral 6 22 6 25 device noninsertable 6 71 directional coupler response compensating for 6 35 discrete markers 1 24 disk formatting 4 53 disk plotting a measurement to 4 11 display elements choosing 4 13 display functions 1 10 active channel display 1 11 titling 1 11 adjusting colors of the display 1 22 blanking the display 1 21 Index data trace saving to display memory 1 19 four channel display 4 Param Displays softkey 1 18 Channel Position softkey 1 1
52. 1 45 Fundamental and 2nd Harmonic Power Levels in dBm CH1 B log MRG 5 dB REF dB i 7 6726 dB Fundafenta Powar 540 600 aga MHz CHL START 16 000 anao MHz STOP 1 888 880 aaa MHz CH2 B log MAG 5 dB REF dB 1 7 1925 dB 2nd Harmon c Po 544 866 aga MHz H Ii N CH2 START 16 000 aano MHz STOP 1 00O 00O 58 MHZ 1 55 Making Measurements Measuring Amplifiers To show the second harmonic s power level relativetothefundamental power in dBc press MORE and select D2 D1toD2 ON This display mode lets you see the relationship between the fundamental and second or third harmonic in dBc Refer to Figure 1 46 Figure 1 46 2nd Harmonic Power Level in dBc CH1 B log MAG 5 dB REF dB 1 7 8742 dB Fundahenta Peudr 500 hoa eda MHz T CH1 START 16 866 844 MHz STOP 1 888 680 A MHz D2 D1 log MAG 5 dB REF dB 1 14 867 dB 2nd Harmon i sea dean ada MHz CH2 START 16 000 ana MHz STOP 1 646 084 BOB MHz Additional Harmonic Measurements Vector network analyzers are commonly used to characterize amplifier gain compressi on versus frequency and power level This is essentially linear characterization since only the relative level of the fundamental input to the fundamental output is measured The narrowband receiver is tuned to a precise frequency and as a result
53. 12180 11A pg656d The open circuit gives thethird independent condition In order to accurately model the phase variation with frequency due to fringing capacitance from the open connector a specially designed shielded open circuit is used for this step The open circuit capacitance is different with each connector type Now the values for E pp directivity Esp source match and Egr reflection frequency response are computed and stored See Figure 7 32 Figure 7 32 Open Circuit Termination e e ss Y A E S 4 7 Mere e m e es o I 126 to Egp a WC Ege Lf pb6113d This completes the calibration procedure for one port devices Device Measurement Now the unknown is measured to obtain a value for the measured response Sj at each frequency Refer to Figure 7 33 7 45 Operating Concepts Measurement Calibration Figure 7 33 Measured S44 e gt e e Y A 941A S1145 e i e oe 511A ERF M FDF I EscS aq pg658d This is the one port error model equation solved for S114 Since the three errors and S41 are now known for each test frequency S414 can be computed as follows S _ Sj Epp 11A 7 Esr Siim Epr Err For reflection measurements on two port devices the same technique can be applied but the test device output port must be terminated in the system characteristic impedance This terminati
54. 180 per point Electrical delay may also be used to compensate for this effect as shown in the next example procedure 1 9 Making Measurements Using Display Functions Using Display Functions This section provides the necessary information for using the display functions These functions are very helpful for displaying measurement data so that it will be easy to read This section covers the following topics Adding titles to your measurements Viewing both primary channels at the same time Viewing and customizing four channel measurements Using the memory traces Using the memory math functions Blankingthe analyzer s display e Changing the colors of the display Making Measurements Using Display Functions Titling the Active Channel Display l Press MORE TITLE toaccess thetitle menu 2 Press ERASE TITLE and enter the title you want for your measurement display f you havea DIN keyboard attached tothe analyzer typethetitle you want from the keyboard Then press ENTER toenter thetitle intothe analyzer You can enter a titlethat has a maximum of 50 characters For more information on using a keyboard with the analyzer refer to the Options and Accessories chapter in the reference guide f you do not have a DIN keyboard attached to the analyzer enter the title from the analyzer front panel a Turn the front panel knob to move the arrow pointer tothe first character of the title b Press SELE
55. 6 66 multiple measurements per page plotting from a disk 4 26 measurements plotting on a full page 4 27 plots outputting toa single page using a plotter 4 25 N dB Point 1 93 names for CSV files 4 44 naming files generated by a sequence 1 102 network analyzer mode 7 83 noise reduction techniques 7 34 averaging 7 34 IF bandwidth reduction 7 35 smoothing 7 35 non coaxial making measurements 6 50 non coaxial devices calibrating for 6 52 noninsertable device 6 71 noninsertable devices calibrating for 6 40 o offset and scale 7 9 offset limits menu 7 82 offset electrical 6 6 offsetting limit lines 1 79 omitting isolation calibration 6 4 one port calibration S11 and S22 7 55 one port error model 7 41 one port reflection error correction 6 26 operating parameters printing or plotting 4 32 operati on dual channel 1 57 single channel 1 57 operation frequency offset 7 87 operation GPIB 7 77 operation harmonic 7 87 operation limit line 7 81 operation system 7 3 operation trace math 7 8 output power 7 10 power coupling options 7 10 outputting measurement results 1 6 Index 7 Index multiple plots to a single page using a plotter 4 25 plot files 4 12 plot files from a PC toa plotter 4 22 singlepage plots usinga printer 4 24 outputting plot files from a PC to an HPGL compatible printer 4 23 sending the exit HPGL mode and form feed sequence to the printer 4 2
56. 7 88 Operating Concepts Differences between 8753 Network Analyzers Differences between 8753 Network Analyzers Table 7 5 Comparing the 8753A B C D Feature 8753A 8753B 8753C 8753D 8753D Opt 011 Fully integrated measurement system built in No No No Yes No test set Test port power range dBm _a _a _a 10 to 85 _a Auto manual power range selecting No No No Yes No Port power coupling uncoupling No No No Yes No Internal disk drive No No No Yes Yes Precision frequency reference Option 1D5 No No No Yes Yes Frequency range low end in kHz 300 300 300 30 30 300 Ext frequency range to 6 GHz Option 006 No Yes Yes Yes Yes 75Q system impedance Option 075 a a a Yes a TRL LRM correction No No No Yes Yes Power meter calibration No Yes Yes Yes Yes nterpolated error correction No Yes Yes Yes Yes M aximum error corrected measurement points 801 1601 1601 1601 1601 Segmented error correction in frequency list mode No No Yes Yes Yes Color CRT No No Yes Yes Yes Test sequencing No Yes Yes Yes Yes Automatic sweep time No Yes Yes Yes Yes External source capability No Yes Yes Yes Yes Tuned receiver mode No Yes Yes Yes Yes Printer plotter buffer No Yes Yes Yes Yes Harmonic measurements Option 002 No Yes Yes Yes Yes Frequency offset mode mixer measurements No Yes Yes Yes Yes dc bias to test device _a a a Yes a Interfaces RS 232 parallel and DIN keyboa
57. Activate four markers by pressing Marker 1 2 3 4 NOTE Observe that the markers appear on all of the grids To activate markers on individual grids press MARKER MODE MENU and set MARKERS toUNCOUPLED Then activate the channel in which you wish to have markers press Marker then select the markers for that channel 3 Turn off the softkey menu and move the marker information off the grids by pressing C The display will be similar to Figure 1 14 1 26 Making Measurements Using Markers Figure 1 14 Marker Information Moved into the Softkey Menu Area H1 L G 311 4i 2 dB REF z dB 1 4831 dB 151 5695306 MHz 1 1 8223 dB ri 6 552606 MHz z2 3 12883 dB MM ERE BAMSEEBZdE 15858 MHz 3 3 148U dB 33 37 588 MHz JENTE 134 888 MHz SPAN 45 888 MHz H8 L G 16 dBe REF 56 dB i2 4q i u 25Y dB 151 589 568 MHz i B 138200 MHz ESSE z 23 315 dB 3 46858 MHz E 22 928 dB Gree ee EHTE 134 888 MHz SPAH 435 888 MHz 2 Sep 1938 12 12 88 CH2 LOG is d amp s REF 56 dB S2i 4 63 13z2 dB 151 583 588 MHz BS EEUU AY Slee Ed PT TT TT Py TT Fra PEE LILLLLLLLI a PETE a Peale esta seca tle T CEHTR 134 006 MHz SPAN 45 888 MHz CH4 LOG 3 dB REF 2 5 dB 22 2 1132 dB 151 583 588 MHz PRm Li ETT TT DEDE ANINE spera E En pg CEHTR 134 888 MHz SPAN 45 888 MHz CH2 Markers i r75 018 dB 1i5 88288 MHz zr 22 4281 dB 129 46856 MHz i 23 489 dB 1339 976068 MH
58. Agilent EPM power sensor and your network analyzer has firmware revision 7 72 or greater a Select the remote interface command set on the power meter by pressing the System Inputs key and the following softkeys Remote Interface Command Set SCPI b Skip step 4 and continue at step 5 The power sensor factors are automatically read by the analyzer e f you are using an Agilent 848X series power sensor or your network analyzer does not have firmware revision 7 72 or greater a Choose the 438A 437 selection on the network analyzer by pressing SET ADDRESSES POWER MTR until it reads POWER MTR 438A 437 b Select the remote interface command set on the power meter by pressing the System Inputs key and the following softkeys Remote Interface Command Set 437B 4 Press PWRMTR CAL LOSS SENSR LISTS CAL FACTOR SENSOR A and enter the correction factors as listed on the power sensor Press ADD FREQUENCY where fff is the frequency of the calibration factor in MHz CAL FACTOR where nnn is the calibration factor number DONE for each correction factor When finished press DONE 5 To perform a one sweep power meter calibration over the RF frequency range at 0 dBm press PWRMTR CAL ONE SWEEP TAKE CAL SWEEP NOTE Because power meter calibration requires a longer sweep time you may want toreduce the number of points before pressing TAKE CAL SWEEP After the power meter calibration is finished return the number of points
59. CAUTION Theanalyzer will overwrite a file on the disk that has the sametitle CAUTION Do not mistake the line switch for the disk eject button Loading a Sequence from Disk For this procedure to work the desired file must exist on the disk in the analyzer drive 1 To view the first six sequences on the disk press MORE LOAD SEQ FROM DISK READ SEQFILE TITLS e fthedesired sequence is not among the first six files press READ SEQ FILE TITLS until the desired file name appears 2 Press the softkey next to thetitle of the desired sequence The disk access light should illuminate briefly NOTE If you know the title of the desired sequence you can title the sequence 1 6 with the name and load the sequence This is also how you can control the sequence number of an imported titled sequence Purging a Sequence from Disk 1 To view the contents of the disk six titles at a time press MORE STORE SEQTO DISK PURGE SEQUENCES READ SEQ FILE TITLS e fthedesired sequence is not among the first six files press READ SEQ FILE TITLS until the desired file name appears 2 Press the softkey next to thetitle of the desired sequence The disk access light should illuminate briefly 1 103 Making Measurements Using Test Sequencing Printing a Sequence 1 Configure a compatible printer to the analyzer Refer to the Options and Accessories chapter of the reference guide 2 To print a sequence press MORE PRINT SEQUENCE and th
60. DEL will likely rem generate an error COPY avoids this rem echo off type hpglinit gt spooler for i in 961 do type i gt gt spooler type exithpgl gt gt spooler copy spooler LPT1 del spooler echo on For example you have the following list of files to plot PLOTOO LL PLOTOO LU PLOTOO RL PLOTOO RU You would invoke the batch print as follows C gt do plot PLOTOO 4 25 Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page from Disk Plotting Multiple Measurements Per Page from Disk The following procedures show you how to store plot files on a LIF formatted disk A naming convention is used so you can later run an HP BASIC program on an external controller that will output the files tothe following peripherals e a plotter with auto feed capability such as the HP 7550B e an HP GL 2 compatible printer such as the Laser et 4 series monochrome or the Desk et 1200C or Desk et 1600C color The program is provided on the CD ROM of example programs that is included in the programmer s guide The file naming convention allows the program to initiate the following toinitialize the printer for HP GL 2 at the beginning of a page toplot multiple plot files on the same page tosend a page eject form feed to the hardcopy device when all plots to the same page have been completed The plot file nameis made up of four parts the first three are generated aut
61. ERI IC Ce e 6 25 One Port Reflection Error COMET ioco cede Ter Rhee PECORE Y CR pc oed aea 6 26 Full Two Part Error Correction i cscicoradcka CODICE XAR RE ORR ERED ERE S 6 29 Power Meter Measurement Calibration leen 6 33 Loss of Power Meter Calibration Data 0 0 ccc eee nnn 6 33 Interpolation in Power Meter Calibration 0 00 eee 6 34 Entering the Power Sensor Calibration Data 0 0 00 cee eee 6 34 Compensating for Directional Coupler Response 0000 e eee eee 6 35 Using Sample and Sweep Correction Mode 002 cece ete ee 6 36 Using Continuous Correctont MOHE 4a ache wok a ER P C PRERIERGC RAU ERErIRQPP e 6 38 Calibrating for Noninsertable Devices 0 0 eee 6 40 Adapter Removal Calibration ES Analyzers Only 00 cee eee eee ee 6 41 Msiched ROARS oicccs peeve Geese t Shee es eR NST RIEIKERTERKEREHERE I ET REGE 6 46 M diy the Cal Kit Thru Deni saa iseit tirit Eniro EG reer ERR ee Y 6 47 Minimizing Error When Using Adapters 0 000 cece eee 6 49 Contents Making Nom Coaxial Measurements iiiassa cR ERAT REREECIEBIX READ LISQEPERIA EK 6 50 POS S up dr Pale dpb ETO DCE E SSE RLS ege eque p V dopkqur quads 6 50 Calibrating Tor Non Coaxial DEVICES simi ca cei nd be ier w seed bed dee ede eee EPA ERR 6 52 TRE ENO COFCBEU BEI ae aco ya dado DO aed ald abad ew a hE RIM do Paid dede 93 4 eS ORES 6 52 LEM EFFDECOITELUDN ii 3b RCDRERERA RI eae PER PXE PAPE e YA
62. ERREUR RE RI ihht kirika h EE CAP RP a ga 7 15 Leoarrnmic Frequency SWeep IHE uusaadeerXxa dad sex TOHpeRIERP PRX E Rkgc Rd pde 7 15 Stepped List Frequency Sweep MZ ssssuwkaakketbbrEREREG wes ewe Ree CPE wee 7 15 Swept List Frequency Sweep Hz 000 eee eee 7 17 Pawe SWeep TIBI cisesz aS EREREREPRA RARI a Y Ribes IEEE Peso des dokn 7 19 CW Time SWEEP SENS erewqd eee x EQ PX eR CRERIPRRHKYqUG EPI CREER E REA 7 19 Selecting Sween MOIES rrisin kiiri iini initi AREE TRERIUG 4E RARE EGER RE 7 19 xi Contents xii S DOREM 23675486 E RIOERHERT HE UP erratis I AES PEEERET EROR 7 20 Understanding S Paramielers a re as qaadapkeqe az dbaereqe qedeep 4a pde kde ep d 7 20 The S Paremeter Men iussi r I np Reece eh eB REOR ER RO EG Hon ERR RC ee n 7 22 Anaha Display POLS ius dd ah RED a xda dud edad bxteparxdar e ERcebq eb 7 24 Log Magnitude FOMIN dueiibedhbbierebevAe eEERERICIYARDATMERE E NATA PEPGY reid ees 7 24 PES FOTOS ee Xx ee a XS Ped eR PP C peser paier p ee 7 24 Group Delay FO Mat ikea FRE ERPNRCRRAS E eae ERRARE ERR dies Obie 7 25 HAIGH Shee LEON dodo HE OAS ad Ue iac Pa PERKS Ge fr bie de Far ard ed ace nd OES 7 26 Polar FOMA iei a4 OE RISO RERKCERERDRERCRERSPREHRETPEPQRERIAPRES 7 27 Linear Magnitude FOTOE a srqesqericriepePBUribh sQePepeREerX4 e RERPRY rTed 7 27 SWR FOOL accexeqexiEigude 4x Gd Re eS DC HE ERE ORAE REED EEE Ren eed 7 28 Beal Foe Wr so bE ands op ia a eaaa ae e eana 7 29 lu snrgddsqp Tp 7 29 Group Delay PI
63. INPUT is selected the imaginary part of the pair is set to zero The DFT filter shape can be altered by changing thelF bandwidth which is a highly effective technique for noise reduction Ratio Calculations These calculations are performed if the selected measurement is a ratio of two inputs for example A R or B R This is a complex divide operation If the selected measurement is absolute such as A or B no calaulations are performed The R A and B values are also split into channel data at this point Sampler IF Correction The next digital processing technique used is sampler IF correction This process digitally corrects for frequency response errors both magnitude and phase primarily sampler rolloff in the analog down conversion path Operating Concepts Processing Sweep To Sweep Averaging Averaging is another noise reduction technique This calculation involves taking the complex exponential average of several consecutive sweeps This technique cannot be used with single input measurements Pre Raw Data Arrays These data arrays store the results of all the preceding data processing operations Up to this point all processing is performed real time with the sweep by thelF processor The remaining operations are not necessarily synchronized with the sweep and are performed by the main processor When full 2 port error correction is on the raw arrays contain all four S parameter measurements required for accuracy en
64. LRM calibration kit defined and saved in the USER KIT as shown in Modifying Calibration Kits on page 7 56 NOTE This must be done before performing the following sequence 2 Press Cal CAL KIT SELECT CAL KIT USERKIT RETURN RETURN CALIBRATE MENU TRL LRM 2 PORT 3 To measure the LRM THRU connec the zero length transmission line between the two test ports 4 To make the necessary four measurements press LRMTHRU 5 To measure the LRM SHORT connec the short to PORT 1 and press S11 REFL LRMSHORT 6 Connec the short to PORT 2 and press S22 REFL LRMSHORT NOTE If loads can be connected to both port 1 and port 2 simultaneously then the following LRM load measurement can be performed using the DO BOTH FWD REV softkey 7 To measure the LRM LOAD disconnect the short and connect the LRM load to PORTI 8 Press LINE MATCH LN MATCHILOAD toaccess the No Loads menu When the displayed trace settles press the softkey corresponding to theload used If a sliding load is used press SLIDING toaccess the Sliding Load menu Position the slide and press SLIDE IS SET 9 When all the appropriate load measurements are complete the load data is measured and the LN MATCHAILOAD softkey label is underlined 10 Connect the load to PORT 2 and press LN MATCH2LOAD 11 Repeat the previous LRM load measurement steps for PORT 2 12 After the measurement is complete press DONE LINE MATCH 13 To measurethe ISOLATION dass press
65. MARKERS COUPLED R JX MKR UNCOUPLED G JB MKR POLAR MKR MENU SMITH MKR MENU RETURN CENTER 134 000 DOO MHz SPAN 30 000 ODO MHz CENTER 134 000 OOD MHz SPAN 30 000 OOO MHz RETURN pg6176_c 7 26 Operating Concepts Analyzer Display Formats Polar Format The POLAR softkey displays a polar format as shown in Figure 7 10 Each point on the polar format corresponds to a particular value of both magnitude and phase Quantities areread vectorally the magnitude at any point is determined by its displacement from the center which has zero value and the phase by the angle counterclockwise from the positive x axis Magnitude is scaled in a linear fashion with the value of the outer cirde usually set to a ratio value of 1 Sincethereis no frequency axis frequency information is read from the markers The default marker readout for the polar format is in linear magnitude and phase A log magnitude marker and a real imaginary marker are availablein the polar marker menu Figure 7 10 Polar Format CH1 11 1 UFS is 703 28 mU 152 5 d 128 850 000 MHz LIN MKR LOG MKR Re Im MKR CENTER 134 000 COO MHz SPAN 30 000 O00 MHz pg6177 c Linear Magnitude Format The LIN MAG softkey displays the linear magnitude format as shown in Figure 7 11 This is a Cartesian format used for unitless measurements such as reflection coefficient magnitude p or transmission coefficient magnitude x and for linear measurement
66. Measurements Mixer Measurement Capabilities Mixer Measurement Capabilities The analyzer is capable of measuring the following mixer frequency converter parameters Figure 2 1 Mixer Parameters Conversion Loss RF Feedthru Conversion Compression Phase Linearity RF Desensitization Group Delay Compared to Reference Output Power Harmonics RF Port IF Port 7779 Isolation Return Loss SWR LO Port pa5160e Transmission characteristics include conversion loss conversion compression group delay and RF feedthrough Reflection characteristics include return loss SWR and complex impedance Characteristics of the signal at the output port indude the output power the spurious or harmonic content of the signal and intermodulation distortion Other parameters of concern are isolation terms induding LO to RF isolation and LO tolF isolation NOTE This chapter uses the following 3 terms when referring to mixer signals LO Local Oscillator LO is normally provided by an external source or internally generated by the frequency converter IF Intermediate Frequency IF is usually the mixer s output signal RF RadioFrequengy RF is usually the mixer s input signal Making Mixer Measurements Measurement Considerations Measurement Considerations In mixer transmission measurements you have RF and LO inputs and an IF output Also emanating from thelF port are several other mixing products of the RF and LO si
67. N STD DONE d Return the averaging to the original state of the measurement and press RESUME CAL SEQUENCE 18 To compute the error coefficients press DONE ENH RESP CAL The analyzer displays the corrected measurement trace The analyzer also shows the notation Cor at the left of the screen indicating that error correction is on Enhanced Reflection Calibration 19 If you are measuring a bilateral device and want to remove the load match error activate the enhanced reflection calibration by pressing ENHANCED RESPONSE ENH REFL on OFF until ON is selected NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures 20 This completes the enhanced response correction procedure You can connect and measure your device under test 6 25 Calibrating for Increased Measurement Accuracy One Port Reflection Error Correction One Port Reflection Error Correction removes directivity errors of the test setup removes source match errors of the test setup removes frequency response of thetest setup You can perform a 1 port correction for an S41 or an 2 measurement The only difference between the two procedures is the measurement parameter that you select NOTE This is the recommended error correction process for all reflection measurements when full two port correction or enhanced response calibration is not
68. PORTS accesses theinput ports menu Analog In Menu This menu allows you to monitor voltage and frequency nodes using the analog bus and internal counter For more information refer to the Service Menus and Error M essages chapter in the service guide Conversion Menu This menu converts the measured reflection or transmission data to the equivalent complex impedance Z or admittance Y values This is not the same as a two port Y or Z parameter conversion as only the measured parameter is used in the equations Two simple one port conversions are available depending on the measurement configuration An Sj or S55 trace measured as reflection can be converted to equivalent parallel impedance or admittance using the model and equations shown in Figure 7 4 Figure 7 4 Reflection Impedance and Admittance Conversions a Z Refl S44 1 S44 Z Refl 1 S4 Yer Y Refl R 7 pg640d 7 22 Operating Concepts S Parameters In a transmission measurement the data can be converted to its equivalent series impedance or admittance using the model and equations shown in Figure 7 5 Figure 7 5 Transmission Impedance and Admittance Conversions S 21 2 1 S Z Trans Z Trans ad 1 vd pg641d NOTE Avoid the use of Smith chart SWR and delay formats for display of Z and Y conversions as these formats are not easily interpreted Input Ports Menu
69. PT ERES 6 56 Create a User Defined LRM Calibration Kit 0 2 00 c eee eee 6 56 Pertorm the LRM Callbrallon seiscextenitehberkkibes4eirgodcd r4 4 d e dH REG PG RR 6 58 Calibrating Using Electronic Calibration ECal 2c sssss sie xb Rx ER Ra 6 60 Set Upthe Measure mel cea er RERERECKEREREREINCRERPQIRATAIBRZVERPSP ERES 6 60 Corinec he ECOL EquIDIento s iqea para rq 3G EXqQu PPEIRRREPISRPCRGHePRRTPPPERRER 6 61 Select the EC al ODORS eciicxur ek DAOIRORRCEEA E PHORE REGERE CREBRA RES 6 62 ParTorm Ehe SUDO Liao dad bee kd dab ee Sa db EE e Peck be ERR PR bobus 6 64 Display the Module Iriformatlofi L4 a RESI TX RRRGAREERTEESXERERTISETX Y VELA RESET 6 66 Perrorm the C ontidence Che Keirin teed pREE PRSE dO Pu pudac r w p dd 6 67 Investigating the Calibration Results Using the ECal ServiceMenu 6 69 Adapter Removal Usi ECA 44 44 ux xia hd e EXER Edda FEHLER doe ERROR de CP EC 6 71 Perform the Z Port Error Corrections Cueaed iibi RP PERI REREEPPEIGOREREd P PERS 6 73 Determinethe Electrical DESY asouaaexeqerkibeirsdebexaodsx4ebXCRkachRPX e PER 6 75 Remove hE S dapUer iusnqeaskbedrcoeE NEAR ORRRT CREER RO Ca dor FORCE EROR FN 6 76 Mer EDS ROHS c ci bei qd rub be NC do Pd e oed Pd 3 dE P e ARIS Pid 6 77 7 Operating Concepts sig Thuschapiel ex435s d ERE irrisa soho Sethi dees ILE ever ELINPRQ A 7 2 Whereto Find Mare Infarmatlolts oa oscadekqe ees d RXdG E scab Pn E PUR RR ER Cn beans 7 2 oyster ODS ANION ausi ard EbSi Pd beis
70. Refer to Figure 7 26 Some of 1 may appear at the measurement system input due to leakage through the test set or through a signal separation device Also some of I may be reflected by imperfect adapters between a signal separation device and the measurement plane The vector sum of the leakage and the miscellaneous reflections is the effective directivity E pf Understandably the measurement is distorted when the directivity signal combines vectorally with the actual reflected signal from the unknown 5414 7 41 Operating Concepts Measurement Calibration Figure 7 26 Effective Directivity E pr Effective Directivity Unknown pg651d Since the measurement system test port is never exactly the characteristic impedance 50 ohms some of the reflected signal bounces off the test port or other impedance transitions further down the line and back tothe unknown adding tothe original incident signal I This effect causes the magnitude and phase of the incident signal to vary as a function of S414 and frequency Leveling the source to produce a constant incident signal reduces this error but since the source cannot be exactly leveled at the test device input leveling cannot eliminate all power variations This re reflection effect and the resultant incident power variation are caused by the source match error Esp as shown in Figure 7 27 Figure 7 27 Source Match E sf Sou
71. THEN POSITIVE PEAKS pg6127d Figure 3 14 shows example cables with discontinuities faults using the low pass step mode with the real format 3 18 Making Time Domain Measurements Time Domain Low Pass Mode Figure 3 14 Low Pass Step Measurements of Common Cable Faults Real Format CH1 S11 Re 5 mU REF O U 1 u 882 mU CH1 S11 Re 5 mU REF O U 1 2 9207 mU hp 3 645 ns hp 3 056 ns G F MARKER h MARKER l 645 ns ju56 ns 360 GQ1 mr 341 91 mm Lr NB M i 1 TE Ke CH1 START O s STOP 10 ns CH1 START O s STOP 10 ns pu a Crimped Cable Capacitive b Frayed Cable Inductive pg6123d Transmission Measurements in Time Domain Low Pass Measuring Small Signal Transient Response Using Low Pass Step Use the low pass mode to analyze the test device s small signal transient response The transmission response of a device to a step input is often measured at lower frequencies using a function generator to provide the step to the test device and a sampling oscilloscope to analyze the test device output response The low pass step mode extends the frequency range of this type of measurement to the maximum frequency of the analyzer The step input shown in Figure 3 15 is the inverse Fourier transform of the frequency domain response of a thru measured at cal
72. The correction will not work properly if a non zero length thru is used unless the calibration kit is modified to change the defined thru tothe length used This is important for measurements of non insertable devices devices having ports that are both male or both female The modified calibration kit must be saved as the user calibration kit and the USER KIT softkey must be selected before the calibration is started 16 To measure the standard when the trace has settled press FWD TRANS THRU or REV TRANS THRU FWD MATCH THRU or REV MATCH THRU STANDARDS DONE The analyzer underlines the softkey label after it makes each measurement 17 Press ISOLATION and select from the following two options T If you will be measuring devices with a dynamic range less than 90 GB press OMIT ISOLATION L1 If you will be measuring devices with a dynamic range greater than 90 dB follow these steps a Connect impedance matched loads to thetest ports I ncludethe adapters that you would include for your device measurement NOTE If you will be measuring highly reflective devices such as filters use the test device connected to the reference plane and terminated with a load for the isolation standard 6 24 Calibrating for Increased Measurement Accuracy Enhanced Frequency Response Error Correction b Activate at least four times more averages than desired during the device measurement c Press RESUME CAL SEQUENCE ISOLATION FWD or REV ISOL
73. Time Domain M easurements Descriptions of all instrument functions are located in the H ardkey Softkey Reference chapter of the reference guide Procedures for using instrument functions making measurements recording measurement results and performing calibrations are located in Chapter 1 Making Measurements and Chapter 6 Calibrating for Increased Measurement Accuracy Operating Concepts System Operation System Operation Network analyzers measure the reflection and transmission characteristics of devices and networks A network analyzer test system consists of the following source signal separation devices receiver display The analyzer applies a signal that is transmitted through the test device or reflected from its input and then compares it with the incident signal generated by the swept RF source Thesignals arethen applied to a receiver for measurement signal processing and display The vector network analyzer integrates a high resolution synthesized RF source test set and a dual channel three input receiver to measure and display magnitude phase and group delay of transmitted and reflected power With Option 010 the analyzer has the additional capability of transforming measured data from the frequency domain to the time domain Other options are explained in Options and Accessories chapter of the reference guide A simplified block diagram of the network analyzer system is shown in Fig
74. Transforms of these measurements result in frequency domain data Such transforms are called forward transforms because the transform from time to frequency is a forward Fourier transform and can be used to measure the spectral content of a CW signal For example when transformed into the frequency domain a pure CW signal measured over time appears as a single frequency spike Thetransform into the frequency domain yields a display that looks similar to a spectrum analyzer display of signal amplitude versus frequency Forward Transform Measurements Figure 3 17 shows an example of a measurement using the Fourier transform in the forward direction from the time domain to the frequency domain Figure 3 17 Amplifier Gain Measurement CH1 B R log MAG 10 dB REF O dB 4 87 509 3B CH1 B R log MAG 10 dB REF O dB 4 87 470 dB 2 1053 s ba O0 Hz L MARKER j4 eer 5B 38 ms CENTER 050 s CW 250 000 000 MHz SPAN 100 s CH1 CENTER O Hz CW 250 000 000 MHz SPAN 800 Hz a CW Time b Transform to Frequency Domain pg6189 c Interpreting the Forward Transform Vertical Axis With thelog magnitude format selected the vertical axis displays dB This format simulates a spectrum analyzer display of power versus frequency 3 22 Making Time Domain Measurements Transforming CW Time Measurements into the Frequency Domain I
75. a filter Figure 1 59 Sloping Limit Lines CHi S2 og MAG 10 dB REF 50 dB 1 69 989 dB 159 fae eda MHz Ads rte rae IF E CENTER 134 888 O88 MHz SPAN 50 0808 B82 MHz aw000012 1 75 Making Measurements Using Limit Lines to Test a Device Creating Single Point Limits In this example procedure the following limits are set e from 23 dB to 28 5 dB at 141 MHz e from 23 dB to 28 5 dB at 126 5 MHz 1 To access the limits menu and activate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE CLEARLIST YES 2 To designate a single point limit line as shown in Figure 1 60 you must define two pointers downward pointing indicating the upper test limit upward pointing indicating the lower test limit Press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SINGLE POINT RETURN ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE SINGLE POINT RETURN Figure 1 60 Example Single Points Limit Line CHL Sg log MAG 19 dB REF 58 dB 1 69 213 dB T 159 daa eda MHz i d MI NETS i CENTER 134 808 0 MHz SPAN 58 0808 O88 MHz aw000013 1 76 Making Measurements Using Limit Lines to Test a Device Editing Limit Segments This example shows you how to edit the upper limit of a limit line 1 To access the limits menu and a
76. a nearly perfect measurement system For example crosstalk due to the channel isolation characteristics of the analyzer can contribute an error equal to the transmission signal of a high loss test device For reflection measurements the primary limitation of dynamic range is the directivity of the test setup The measurement system cannot distinguish the true value of the signal reflected by the test device from the signal arriving at the receiver input duetoleakage in the system For both transmission and reflection measurements impedance mismatches within the test setup cause measurement uncertainties that appear as ripples superimposed on the measured data Error correction simulates an improved analyzer system During the measurement calibration process the analyzer measures the magnitude and phase responses of known standard devices and compares the measurement with actual device data The analyzer uses the results to characterize the system and effectively remove the system errors from the measurement data of a test device using vector math capabilities internal to the network analyzer When you use a measurement calibration the dynamic range and accuracy of the measurement are limited only by system noise and stability connector repeatability and the accuracy to which the characteristics of the calibration standards are known 7 37 Operating Concepts Measurement Calibration What Causes Measurement E rrors Network analysis
77. approximately the same delay as the device under test This length of cable can be inserted between the R CHANNEL IN and OUT connectors on the front panel of the analyzer The delay of this cable must be less than 5us 5 8 Optimizing Measurement R esults Increasing Sweep Speed Increasing Sweep Speed You can increasethe analyzer sweep speed by avoiding the use of some features that require computati onal time for implementation and updating such as bandwidth marker tracking You can also increase the sweep speed by making adjustments to the measurement settings The following suggestions for increasing sweep speed are general rules that you should experiment with e use swept list mode e decrease the frequency span setthe auto sweep time mode widen the system bandwidth reducethe averaging factor reducethe number of measurement points setthe sweep type use chop sweep mode e use external calibration usefast 2 port calibration mode To Use Swept List Mode When using a list frequency sweep choosing swept list mode can increase throughput by up to 6 times over stepped list mode This mode takes data while sweeping through each list segment In addition this mode expands the list table to include test port power and IF bandwidth Selectable IF bandwidths can increase the throughput of the measurement by allowing the user to specify narrow bandwidths only where needed For in depth information on swept li
78. are observed this indicates that the electrical delay of the adapter was not specified within a quarter wavelength over the frequency range of interest To correct this recall both cal sets since the data was previously stored to disk change the adapter delay and press REMOVE ADAPTER 6 77 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal 6 78 7 Operating Concepts 7 1 Operating Concepts Using This Chapter Using This Chapter Th is chapter provides conceptual information on how specific functions of the network analyzer operate The following topics are discussed System Operation on page 7 3 Processing on page 7 6 Output Power on page 7 10 Sweep Time on page 7 11 Source Attenuator Switch Protection on page 7 13 Channel Stimulus Coupling on page 7 14 Sweep T ypes on page 7 15 S Parameters on page 7 20 Analyzer Display Formats on page 7 24 Electrical Delay on page 7 33 Noise Reduction Techniques on page 7 34 Measurement Calibration on page 7 37 Calibration Routines on page 7 54 Modifying Calibration Kits on page 7 56 TRL LRM Calibration GPIB Operation on page 7 77 Limit Line Operation on page 7 81 Knowing the Instrument M odes on page 7 83 Where to Find More Information 7 2 Operation concepts relating to mixer measurements and time domain measurements can be found in Chapter 2 Making Mixer Measurements and Chapter 3 Making
79. band limits Clear all frequency band limits Changing Existing Frequency Band Limits Existing frequency band limits may be changed for testing the ripple This procedure guides you through changing the existing frequency band limits 1 To access the ripple test edit menu from the ripple test menu press EDIT RIPL LIMIT 2 Enter the frequency band whose limits you want to change by pressing a FREQUENCY BAND b Thenumeric key indicating the frequency band number that you are changing The frequency band number is located in the left column of the list of frequency bands 1 83 Making Measurements Using Ripple Limits to Test a Device 3 Makethe changes to the selected band by pressing a MINIMUM FREQUENCY and the new value to change the lower frequency of the frequency band b MAXIMUM FREQUENCY and the new value to change the upper frequency of the frequency band C MAXIMUM RIPPLE and the new decibel value to change the maxi mum allowable ripple of the frequency band Terminate the new decibel value with the key 4 Repeat steps 2 and 3 for additional frequency bands 5 After you have entered the necessary changes to the ripple test frequency band parameters return tothe ripple test menu by pressing DONE Adding Additional Frequency Bands More frequency band limits may be added for testing the ripple This procedure guides you through adding the more frequency band limits The network analyzer allows you to en
80. be connected directly into a transmission test configuration is considered to be noninsertable Some examples of noninsertabletest devices are afixture with two female SMA connectors or a cable with two maletype N connectors anadapter with SMA male and type N female or any combination connector type and Sex Therefore one of the following calibration methods must be performed adapter removal ES analyzers only e matched adapters e modify the cal kit thru definition Figure 6 12 Noninsertable Device NETWORK ANALYZER Reference Reference Port 1 Port 2 pa593e 6 40 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Adapter Removal Calibration ES Analyzers Only Adapter removal calibration provides the most complete and accurate procedure for measuring noninsertable devices The following adapters are needed e Adapter A1 which mates with port 1 of the device must be installed on test set port 1 Adapter A2 which mates with port 2 of the device must beinstalled on test set port 2 Adapter A3 must match the connectors on the device under test DUT NOTE Adapter A1 and Adapter A2 become part of the test setup to allow connection to the DUT Adapter A3 is used during calibration only Its effects will be removed Figure 6 13 Adapters Needed NETWORK ANALYZER Reference Reference Port 1 Port 2 Other requirements include Calibration standard
81. between the measurements in either list mode then use the swept list mode f the memory trace indicates that there is more attenuation in swept list mode it may be dueto IF delay You can usually remedy this problem by increasing the sweep time NOTE IF bandwidths of 30 to 10 Hz cause the sweep or that segment of the sweep to always be stepped thus eliminatinglF delay To Decrease the Frequency Span The hardware of the network analyzer sweeps the frequency range in separate bands where switching from band to band takes time Modify the frequency span to eliminate as many band switches as possible while maintaining measurement integrity Refer to the following table to identify the analyzer s band switch points Table 5 3 Band Switch Points Band Frequency Span Band Frequency Span 0 0 01 MHz to 0 3 MHz 7 178 MHz to 296 MHz 1 0 3 MHz to 3 3 MHz 8 296 MHz to 536 MHz 2 3 3 MHz to 16 MHz 9 536 MHz to 893 MHz 3 16 MHz to 31 MHz 10 893 MHz to 1 607 GHz 4 31 MHzto 61 MHz 11 1 607 GHz to 3 GHz 5 61 MHzto 121 MHz 12 Option 006 3 GHz to 4 95 GHz 6 121 MHzto 178 MHz 13 Option 006 4 95 GHz to 6 GHz 5 10 Optimizing Measurement R esults Increasing Sweep Speed To Set the Auto Sweep Time Mode Auto sweep time mode is the default mode the preset mode This mode maintains the fastest sweep speed possible for the current measurement settings Press SWEEP TIME 0 tore enter the auto
82. correction each sweep mode e sample and sweep correcti on single sweep mode Thetime required to perform a power meter calibration depends on the source power number of points tested and number of readings taken Refer tothe Specifications and Characteristics chapter of the reference guide for characteristic power meter calibration sweep speeds and accuracy Regardless of the measurement application the analyzer s source can only supply corrected power within the selected power range If power outside this range is requested the annotation will change to PC Loss of Power Meter Calibration Data The power meter calibration data will belost by committing any of the following actions Turning power off Turning off the instrument erases the power meter calibration table Changing sweep type If the sweep type is changed linear log list CW power while power meter calibration is on the calibration data will be lost However calibration data is retained if you change the sweep type while power meter calibration is off Changing frequency Power meter calibration data will also be lost if the frequency is changed in log or list mode but it is retained in linear sweep mode Pressing Preset Presetting the instrument will erase power meter calibration data If the instrument state has been saved in a register using the key you may recall the instrument state and the data will be restored Saving the instrument state will n
83. dB is 2 0026 dB ott r LOG MAG 137 4150 01 6 MHz PHASE DELAY SMITH CHART POLAR LIN MAG SWR ay MORE CENTER 134 000 000 MHz SPAN 30 000 O00 MHz pg6184 c Phase Format The PHASE softkey displays a Cartesian format of the phase portion of the data measured in degrees This format displays the phase shift versus frequency The phase response of the same filter in a phase only format is illustrated in Figure 7 7 7 24 Figure 7 7 Phase Format a CH1 S21 phaes 100 d REF SOO md LOG MAG DELAY SMITH CHART POLAR LIN MAG REAL SWR CENTER 134 000 000 MHz SPAN 2 000 000 MHz pg6178 c Group Delay Format PHASE Operating Concepts Analyzer Display Formats The DELAY softkey selects the group delay format with marker values given in seconds The bandpass filter response formatted as group delay is shown in Figure 7 8 Group delay principles are described in the next few pages Figure 7 8 Group Delay Format 15 Jun 1994 15 05 13 CH1 S2 delay 10 ns REF s PRm Aug 16 START 75 000 200 MHz STOP 175 800 G88 MHz 7 25 Operating Concepts Analyzer Display Formats Smith Chart Format The SMITH CHART softkey displays a Smith chart format Refer to Figure 7 9 This is used in reflection measurements to provide a readout of the data in terms of imped
84. dual channel Theanalyzer measures the fundamental on one channel while measuring the second or third harmonic on the other channel Theanalyzer measures the second harmonic on one channel while measuring the third harmonic on the other channel Usingthe COUPLE PWR ON off feature the analyzer measures the fundamental on channel 1 while measuring the second or third harmonic in dBc on channel 2 Usingthe COUPLE PWR ON off feature the analyzer couples power between channels 1 and 2 This is useful when you are using the D2 D1 to D2 feature because you can change fundamental power and see the resultant change in the harmonic power 7 87 Operating Concepts Knowing the Instrument Modes Theanalyzer shows the fundamental frequency value on the display H owever a marker in the active entry area shows the harmonic frequency in addition to the fundamental If you use the harmonic mode the annotation H 2 or H 3 appears on the left hand side of the display The measured harmonic cannot not exceed the frequency limitations of the network analyzer s receiver Coupling Power Between Channels 1 and 2 COUPLE PWR ON off is intended to be used with the D2 D1toD2 on OFF softkey You can use the D2 D1 to D2 function in harmonic measurements where the analyzer shows the fundamental on channel 1 and the harmonic on channel 2 D2 D1 to D2 ratios the two showing the fundamental and the relative power of the measured harmonic in dBc You must u
85. external disk setup procedure in Saving an Instrument State on page 4 36 3 Press RETURN and then use the lt 3 or X keys or the front panel knob to highlight the name of the file that you want to rename 4 Press RETURN FILE UTILITIES RENAME FILE ERASE TITLE 5 Turn the front panel knob to point to each character of the new file name pressing SELECT LETTER when the arrow points to each character Press BACK SPACE if you enter an incorrect character After you have selected all the characters in the new file name press DONE NOTE Renaming files may also be done by using the optional external keyboard Recalling a File l Press SELECT DISK 2 Choose from the following storage devices 1 INTERNAL MEMORY 1 INTERNAL DISK 1 EXTERNAL DISK If necessary refer to the external disk setup procedure in Saving an Instrument State on page 4 36 3 Press the C or X keys or the front panel knob to highlight the name of the file that you want to recall 4 Press RETURN RECALL STATE 4 52 Printing Plotting and Saving Measurement Results Formatting a Disk Formatting a Disk 1 Press Save Recall FILE UTILITIES FORMAT DISK 2 Choose the type of format you want 1 FORMAT LIF Ll FORMAT DOS 3 Press FORMAT EXT DISK YES Solving Problems with Saving or Recalling Files f you encounter a problem when you are storing files to disk or the analyzer internal memory check the following li
86. fixed marker activating 1 29 moving marker information off of the grids 1 26 polar format markers 1 32 setting measurement parameters 1 34 smith chart markers 1 33 specific amplitude searching for 1 39 uncoupling display markers 1 31 masking 3 26 matched adapters 6 46 maximum amplitude searching for 1 39 maximum and minimum 1 93 maximum bandwidth 1 93 measurement accuracy increasing 5 4 calibration power meter 6 33 fault location using low pass 3 18 high dynamic range 2 22 isolation example 2 42 non coaxial 6 50 plotting toa disk 4 11 printing or plotting results 4 3 reflection response 3 9 results outputting 1 6 results saving 4 37 results saving graphically 4 45 setting 1 5 time domain 3 3 transmission measurements in time domain low pass 3 19 transmission response 3 5 measurement calibration 7 37 accuracy enhancement 7 37 7 51 characterizing microwave systematic errors 7 41 measurement errors 7 38 measurement considerations 2 4 eliminating unwanted mixing and leakage signals 2 6 frequency offset modeoperation 2 10 how RF and IF are defined 2 7 LO frequency accuracy and stability 2 10 minimizing source and load mismatches 2 4 power meter calibration 2 10 reducing the effect of spurious responses 2 5 measurement data 1 20 dividing by the memory trace 1 20 viewing 1 20 measurement data trace 1 20 subtracting memory trace 1 20 measurement error crosstalk 7 40
87. followed by x7 CAUTION Do not exceed the maximum test port power level that is printed on the front panel of your network analyzer Exceeding this maximum power level may damage your analyzer Reduce the Receiver Noise Floor Refer to Reducing Noise on page 5 15 Reduce the Receiver Crosstalk Refer to Reducing Receiver Crosstalk on page 5 16 5 14 Optimizing Measurement R esults Reducing Noise Reducing Noise You can usetwo analyzer functions to help reduce the effect of noise on the data trace activate measurement averaging reduce system bandwidth To Activate Averaging The noiseis reduced with each new sweep as the effective averaging factor increments 1 Press AVERAGING FACTOR 2 Enter a value followed by x1 3 Press AVERAGING ON Refer to Averaging on page 7 34 for more information To Change System Bandwidth By reducing the system bandwidth you reduce the noise that is measured during the sweep While averaging requires multiple sweeps to reduce noise narrowing the system bandwidth reduces the noise on each sweep however the sweep will be slower 1 Press Avg IF BW 2 Enter thelF bandwidth value that you want followed by x1 Narrower system bandwidths cause longer sweep times When in auto sweep time mode the analyzer uses the fastest sweep time possible for any selected system bandwidth Auto sweep time mode is the default preset analyzer setting NOTE Another capability
88. for example 3MHZ2Z press LIMIT MENU LIMITLINE LIMIT LINE OFFSETS STIMULUS OFFSET The analyzer beeps and a FAIL notation appears on the analyzer display as shown in Figure 1 61 Figure 1 61 Example Stimulus Offset of Limit Lines CHL Soy tog MAG 10 dB REF 50 dB 1 68 829 dB i159 aa Oda MHz LIMIT STIMULUS OFFSE i 3 MHz ar b RRR acs al EH Wy NT sey CENTER 134 888 8688 MHz SPAN 58 980 288 MHz aw000014 e Toreturn to 0 Hz offset press STIMULUS OFFSET 9 Tooffset all of the segments in the limit table by a fixed amplitude press AMPLITUDE OFFSET The analyzer beeps and a FAIL notation appears on the analyzer display e Toreturn to 0 dB offset press AMPLITUDE OFFSET Tooffset the amplitude offset value by the active marker reading press MARKER AMP OFS Pressing AMPLITUDE OFFSET shows the current value 1 79 Making Measurements Using Ripple Limits to Test a Device Using Ripple Limits to Test a Device Setting Up theList of Ripple Limits to Test Twotasks areinvolved in preparing for ripple testing First set up the analyzer settings to view the frequency of interest Second set up the analyzer totest over the appropriate frequencies against your specific limits This example will show you how to set up the analyzer totest ripple limits In this example we will be testing the pass ba
89. for the bandwidth test press MAXIMUM BANDWIDTH Running a Bandwidth Test After setting up the bandwidth limits you are ready to run the bandwidth test and check the test results For this example we will Start the test Display the bandwidth markers Review the test results 1 93 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter Activating the Bandwidth Test 1 Start the bandwidth test by pressing the BW TEST on OFF softkey until ON is displayed The bandwidth test continues to run until the softkey is returned tothe OFF position Thetest displays a message in the upper left corner of the graticule showing that the bandwidth test is being performed and the channel on which thetest is being performed For example BW1 indicates that the bandwidth test is being run on channel 1 See Figure 1 72 Thetest also displays a message indicating whether the filter passes or fails the bandwidth test When the filter is passing the test the message indicates Pass When the filter is failing thetest the failure message indicates either Wide when the pass band is wider than the maximum bandwidth input or Narrow when the pass band is narrower than the minimum bandwidth input When the filter passes the bandwidth test the color of the bandwidth test Pass message is green When the filter fails the bandwidth test the color of the bandwidth test Wide N arrow message is red Figure 1 72 Filter Pass Band with B
90. frequency 1 85 frequency 1 82 bandwidth 1 93 bandwidth markers displaying 1 94 bandwidth test activating 1 94 running 1 93 1 96 setting up limits 1 91 1 93 bandwidth testing 1 91 1 96 bandwidth value displaying 1 95 bandwidth searching for 1 41 basic measurements making 1 4 bilateral device 6 22 6 25 blanking the display 1 21 block receiver 7 4 built in synthesized source 7 4 Cc cables interconnecting 5 4 calculating statistics of measurement data 1 42 calculations ratio 7 7 calibrating for non coaxial devices 6 52 TRL error correction 6 52 TRM error correction 6 56 calibrating for noninsertable devices 6 40 adapter removal 6 41 6 71 matched adapters 6 46 modifying the cal kit through definition 6 47 calibrating the analyzer receiver to measure absolute power 6 39 calibration E Cal 6 60 6 70 electronic See ECal power meter 2 10 calibration considerations 6 4 calibration standards 6 5 darifying type N connector sex device measurements 6 4 error correction stimulus state 6 9 frequency response of calibration standards 6 6 interpolated error correction 6 8 measurement parameters 6 4 omitting isolation calibration 6 4 restarting a calibration 6 5 saving calibration data 6 5 calibration data saving 6 5 7 65 calibration kit menu 7 57 defining standard menus 7 58 label dass menu 7 64 label kit menu 7 64 label standard menu 7 61 specify class menu 7
91. function is active its stimulus valueis displayed in the active entry area and can be controlled with the knob the step keys or the numeric keypad The active marker can be moved to any point on the trace and its response and stimulus values are displayed at the top right corner of the graticule for each displayed channel in units appropriate to the display format The displayed marker response values are valid even when the measured data is above or below the range displayed on the graticule f you activate both data and memory traces the marker values apply to the data trace f you activate only the memory trace the marker values apply to the memory trace f you activate a memory math function data memory or data memory the marker values apply to the trace resulting from the memory math function Marker values are normally continuous that is they are interpolated between measured points They can also be set to read only discrete measured points Markers normally have the same sti mulus values for all channels or they can be uncoupled sothat each channel has independent markers regardless of whether stimulus values are coupled or dual channel display is on To Use Continuous and Discrete Markers The analyzer can either place markers on discrete measured points or move the markers continuously along a trace by interpolating the data value between measured points Press MARKER MODE MENU and select one of the following c
92. in this case the computed slope varies as the aperture Af is increased See Figure 7 17 A wider aperture results in loss of the fine grain variations in group delay This loss of detail is the reason that in any comparison of group delay data it is important to know the aperture that was used to make the measurement Figure 7 17 Variations in Frequency Aperture Frequency Reduce Noise Larger S N Miss Fine Variations In Phase Linearity pg6181 c In determining the group delay aperture there is a trade off between resolution of fine detail and the effects of noise Noise can be reduced by increasing the aperture but this will tend to smooth out the fine detail More detail will become visible as the aperture is decreased but the noise will also increase possibly to the point of obscuring the detail A good practice is to use a smaller aperture to assure that small variations are not missed then increase the aperture to smooth the trace 7 31 Operating Concepts Analyzer Display Formats The default group delay aperture is the frequency span divided by the number of points across the display To set the apertureto a different value turn on smoothing in the average menu and vary the smoothing aperture The aperture can be varied up to 2096 of the span swept Group delay measurements can be made on linear frequency log frequency or list frequency sweep types not in CW or power sweep Group delay apert
93. instrument is turned off tkey to start modifying a sequence 2 To select a sequence position in which to store your sequence press SEQUENCE 1SEQ1 This choice selects sequence position 1 The default title is seo1 for this sequence Refer to Changing the a sequence title Sequence Title on page 1 102 for information on how to modify 3 Tocreate a test sequence enter the parameters for the measurement that you wish to make For this example a SAW filter measurement is set up with the following parameters SELECT DISK INTERNAL MEMORY Usethe front panel knob to scroll until Preset State is highlighted on the display RETURN RECALL STATE Trans FWD S21 B R LOG MAG Scale Ref AUTOSCALE 1 98 Making Measurements Using Test Sequencing The previous keystrokes will create a displayed list as shown Start of Sequence RECALL PRST STATE Trans FWD S21 B R LOG MAG CENTER 134 M u SPAN 50 M u SCALE DIV AUTO SCALE 4 To complete the sequence creation press DONE SEQ MODIFY CAUTION When you create a sequence the analyzer stores it in volatile memory where it will be lost if you switch off the instrument power except for sequence 6 which is stored in the analyzer non volatile memory H owever you may store sequences to a floppy disk Running a Sequence To run a stored test sequence press and the softkey labeled with desired sequence number Or press DO SEQUENCE and the softkey lab
94. is immune from harmonic distortion You may want to quantify the harmonic distortion itself Figure 1 47 illustrates a simultaneous measurement of fundamental gain compression and second harmonic power as a function of input power 1 56 Making Measurements Measuring Amplifiers Figure 1 47 Gain Compression and 2nd Harmonic Output Level CH1 S24 log MAG 2 dB REF 10 d8 e CH1 START 5 0 dBm CW 1 200 000 000 MHz STOP 10 0 dBm CHe B log MAG 10 dB AEF 30 dB a s k 07 7 pg6164d Understanding Harmonic Operation Single Channel Operation You can view the second or third harmonic alone by using only one of the analyzer s channels Dual Channel Operation To make the following types of measurements uncouple channels 1 and 2 and switch on dual channel The analyzer measures the fundamental on one channel while measuring the second or third harmonic on the other channel The analyzer measures the second harmonic on one channel while measuring the third harmonic on the other channel Usingthe COUPLED PWR ON off feature the analyzer measures the fundamental on channel 1 while measuring the second or third harmonic in dBc on channel 2 Usingthe COUPLED PWR ON off feature the analyzer couples power between channels 1 and 2 This is useful when you are using the D2 D1 to D2 feature because you can change fundamental power and see the resultant change in
95. length of the non zero length thru standard In this configuration the measurement will be properly calibrated up to the point of the device Operating Concepts GPIB Operation GPIB Operation This section contains information on the following topics local key GPIB controller modes instrument addresses usingthe parallel port Key This key is allows you to return the analyzer to local front panel operation from remote computer controlled operation This key will also abort a test sequence or hardcopy print plot In this local mode with a controller still connected on GPIB you can operate the analyzer manually locally from the front panel This is the only front panel key that is not disabled when the analyzer is remotely controlled over GPIB by a computer The exception to this is when local lockout is in effect this is a remote command that disables the key making it difficult to interfere with the analyzer while it is under computer control n addition the key accesses the GPIB menu where you can set the controller mode and to the address menu where you can enter the GPIB addresses of peripheral devices and select plotter printer ports You can also set the mode of the parallel port here The GPIB menu consists of the following softkeys SYSTEM CONTROLLER TALKER LISTENER USE PASS CONTROL SET ADDRESS e PARALLEL GPIB DIAG on OFF DISK UNIT NUMBER VOLUME NUMBER Theanalyzer is fa
96. list for sequence 2 as shown Start of Sequence INTERNAL DISK DATA ARRAY ON FILENAME FILE 0 SAVE FILE 3 Tocreate a sequence that prompts you totune a device that has failed the limit test and calls sequence 1 to retest the device press NEW SEQ MODIFY SEQ SEQUENCE 3SEQ3 MORE TITLE TUNE DE V I C E DONE SPECIAL FUNCTIONS PAUSE RETURN DO SEQUENCE SEQUENCE 1SEQ1 DONE SEQ MODIFY This will create a displayed list for sequence 3 as shown Start of Sequence TLE UNE DEVICE EQUENCE I I S P D AUSE O SEQUENCE SEQUENCE 1 You will see the tune device prompt in thetitle area or the sequence will pause until you press the CONTINUE SEQUENCE key 1 118 2 Making Mixer Measurements 2 1 Making Mixer Measurements Using This Chapter Using This Chapter This chapter contains the following nformation on mixer measurement capabilities nformation on mixer measurement considerations Example procedures for making the following mixer measurements Conversion loss using the frequency offset mode High dynamic range swept RF IF conversion loss High dynamic range configuration with Option 014 Fixed IF measurements Group delay measurements Amplitude and phase tracking Conversion compression using the frequency offset mode Isolation Measurements SWR Return Loss Making Mixer
97. lowering the noise floor smoothing finds the mid value of the data Use it to reduce relatively small peak to peak noise values on broadband measured data Use a sufficiently high number of display points to avoid misleading results Do not use smoothing for measurements of high resonance devices or other devices with wide trace variations as it will introduce errors into the measurement Smoothing is used with Cartesian and polar display formats It is also the primary way to control the group delay aperture given a fixed frequency span Refer to Group Delay Principles on page 7 29 In polar display format large phase shifts over the smoothing aperture will cause shifts in amplitude since a vector average is being computed The effect of smoothing on a log magnitude format trace is illustrated in Figure 7 19 Figure 7 19 Effect of Smoothing on a Trace 10 dB REF SO dB CH1 S24 leg MAG 10 dB REF SO dB CH1 S21 log MAG N a LLL START 2 000 000 000 MHz STOP 2 300 000 000 MHz START 2 090 000 ODO MHz STOP 2 300 000 000 MHz pg 170 c IF Bandwidth Reduction IF bandwidth reduction lowers the noise floor by digitally reducing the receiver input bandwidth It works in all ratio and non ratio modes It has an advantage over averaging as it reliably filters out unwanted responses such as spurs odd harm
98. mathematics for this comprehensive model use all forward and reverse error terms and measured values Thus to perform full error correction for any one parameter all four S parameters must be measured Applications of these error models are provided in the calibration procedures described in Chapter 5 Optimizing Measurement Results Enhanced Response Calibration Error Model Enhanced response calibration uses the same error model as the forward configuration portion of Figure 7 38 In the response portion the source and load match effects are full y accounted for giving the same accuracy to the forward tracking term Erg as the two port calibration During the measurement the enhanced response calibration performs a correction which is mathematically the same as setting the values of E p E n Esr Expr Epp to zero 0 and the values of Egg and Erp to one 1 in the equations for S11 and S21 shown in Figure 7 39 7 50 Operating Concepts Measurement Calibration Figure 7 39 Full Two Port Error Model Equations ree d ts SM Exe Siam Exe SR Cir ETF ETR S41A Stim Epr m Epp S314 Exe Sig Exe Es Esp EirEiR E ERF j ETF ETR Xx n ig E Esr Erp Sm fr ERR E I TF 521A Stim Epr a Epng S3
99. maximum ripple minus the absolute ripple value within the frequency band This value is displayed in dB A positive value is the margin by which the ripple passes the ripple test in the frequency band A negative value is the margin by which the ripple fails the ripple test in the frequency band 1 89 Making Measurements Using Ripple Limits to Test a Device Figure 1 68 shows the rippletest with margin ripple value displayed for F requency Band 2 Notice that Frequency Band 2 passes theripple test with a margin of 0 097 dB The plus sign indicates this band passes the ripple test by the amount displayed A minus sign would indicate that the band failed by the displayed amount Figure 1 68 Filter Pass Band with Margin Ripple Value for Band 2 Activated 2 Jun 2888 18 41 12 CHI 211 Los 1 dB REF 3 dB RIPL1 FRIL B2Z 897 dH Frequency Band 2 Margin Ripple Value Lu Lo START 188 000 BBB GHz STOP 3 508 000 EGO GHz pa5201e 1 90 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter Using Bandwidth Limits to Test a Bandpass Filter The bandwidth testing mode can be used totest the bandwidth of a bandpass filter The bandwidth test finds the peak of a signal in the passband and locates a point on each side of the passband at an amplitude below the peak that you specify during the test setup The frequency between the
100. measured data versus the module s premeasured calibration data for the remainder of the module states in addition to the confidence state Access the ECal Service menu by pressing ECal SERVICE from the Confidence Check menu The ECal Service menu softkeys are ECal STD Toggles the analyzer to show the data for the following calibration states CONF Confidence THRU e ISOL Isolation S11REFL S11 Reflection S22 REFL S22 Reflection REFL STD Toggles between the available S11 and S22 reflection states listed in the ECal STD softkey described above e SILREFL allows up to 13 reflection states e S22 REFL allows up to 13 reflection states 6 69 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal NOTE When there is no premeasured calibration data for a given state and measurement parameter a warning is displayed indicating that no module date is available PARAMETER TRACE TYPE Toggles the analyzer to show the data for the following S parameters S11 S21 S12 S22 Toggles through the following trace types DATA amp ME M displays two traces representing the measured E Cal results and the module s premeasured calibration data trace DATA MEM displays a single trace representing a ratio of the measured E Cal results to the module s premeasured calibration data DATA ME M displays a single trace representing the difference between the measured E Cal r
101. measurement errors can be separated into systematic random and drift errors Correctable systematic errors are the repeatable errors that the system can measure These are errors due to mismatch and leakage in the test setup isolation between the reference and test signal paths and system frequency response The system cannot measure and correct for the non repeatable random and drift errors These errors affect both reflection and transmission measurements Random errors are measurement variations due to noise and connector repeatability Drift errors indude frequency drift temperature drift and other physical changes in the test setup between calibration and measurement Theresulting measurement is the vector sum of the test device response plus all error terms The precise effect of each error term depends upon its magnitude and phase relationship to the actual test device response In most high frequency measurements the systematic errors are the most significant source of measurement uncertainty Since each of these errors can be characterized their effects can be effectively removed to obtain a corrected value for the test device response For the purpose of vector accuracy enhancement these uncertainties are quantified as directivity source match load match isolation crosstalk and frequency response tracking The description of each of these systematic errors follows Random and drift errors cannot be precisely quantified
102. measurement made over a 200 ms time span choose a span of 1 kHz or less on either side of the center frequency see Figure 3 20 That is choose a total span of 2 kHz or less 3 24 Making Time Domain Measurements Transforming CW Time Measurements into the Frequency Domain Figure 3 20 Range of a Forward Transform Measurement CH1 B log MAG 10 dB REF 50 dB A 20 863 dB T ic o Hz CH3 START 1 kHz CW 250 000 000 MHz STOP 1 kHz pg6186 c To increase the frequency domain measurement range increase the span The maximum rangeisinversely proportional tothe sweep time therefore it may be necessary to increase the number of points or decrease the sweep ti me Because increasing the number of points increases the auto sweep time the maximum range is 2 kHz on either side of the selected CW time measurement center frequency 4 kHz total span To display a total frequency span of 4 kHz enter the span as 4000 Hz 3 25 Making Time Domain Measurements Masking Masking Masking occurs when a discontinuity fault closest to the reference plane affects the response of each subsequent discontinuity This happens because the energy reflected from the first discontinuity never reaches subsequent discontinuities For example if a transmission line has two discontinuities that each reflect 5096 of the incident voltage the time domain response real format shows the corre
103. measurement plane All incident energy is absorbed With S414 0 the equation can be solved for E pp the directivity term In practice of course the perfect load is difficult to achieve although very good broadband loads are available in the compatible calibration kits 7 43 Operating Concepts Measurement Calibration Figure 7 29 Perfect Load Termination e gt e e Y A 500 4147 9 e m e S 0 Err 11M DF 1 Egp 0 pg654d Since the measured value for directivity is the vector sum of the actual directivity plus the actual reflection coefficient of the perfect load any reflection from the termination represents an error System effective directivity becomes the actual reflection coefficient of the near perfect load as shown in Figure 7 30 In general any termination having a return loss value greater than the uncorrected system directivity reduces reflection measurement uncertainty Figure 7 30 Measured Effective Directivity Actual Directivity Before Tof Load Correction TL 0 Measured Directivity Before Correction D Effective Directivity After Correction D Dy T pb6112d Next a short circuit termination whose response is known to a very high degree is used to establish another condition as shown in Figure 7 31 7 44 Operating Concepts Measurement Calibration Figure 7 31 Short Circuit Termination e gt e oe Y A S
104. measurements This procedure may be adequate for measurement of well matched high loss devices Enhanced Response Calibration The enhanced response calibration activated by pressing the ENHANCED RESPONSE softkey within the calibrate menu provides a one port calibration to correct for directivity source match and frequency response for reflection measurements and corrects for source match as well as frequency response for transmission measurements Enhanced response calibration improves accuracy in transmission measurements compared to a response calibration or a response and isolation calibration but it is not as accurate as a full 2 port calibration Enhanced Reflection Calibration The enhanced reflection calibration is activated by selecting ENH REFL ON off under the ENHANCED RESPONSE menu 7 54 Operating Concepts Calibration Routines The enhanced reflection calibration effectively removes load match error from the enhanced response calibration performed on a bilateral device A bilateral device has an identical forward S254 and reverse transmission S12 response Most passive devices such as filters attenuators or switches are bilateral Some passive devices circulators isolators and most active devices do not have identical forward and reverse transmission responses and enhanced reflection calibration will not work with these devices Sj and S5 One Port Calibration TheS44 and S55 one port calibration procedur
105. mode calibrate 1 69 characteristics of the filter 1 66 device under test connect 1 65 measure 1 69 measurement parameters 1 67 stepped list mode 1 65 totest a device 1 65 swept list mode using 5 9 swept RF IF conversion loss high dynamic range 2 18 Switch protection source attenuator 7 13 SWR format 7 28 SWR return loss 2 48 synthesized source built in 7 4 system bandwidth changing 5 15 bandwidth widening 5 11 system controller mode 7 78 System operation 7 3 built in synthesized source 7 4 microprocessor 7 4 receiver block 7 4 required peripheral equipment 7 5 Systematic errors 7 41 T taking care of microwave connectors 5 3 talker listener mode 7 78 target amplitude searching for 1 40 temperature drift 5 5 terminology TRL 7 67 test bandwidth 1 91 1 96 ripple limit 1 80 1 90 test port coupling 7 10 test port input power increasing 5 14 test sequencing 1 97 changing the sequence title 1 102 clearing a sequence from memory 1 101 creating a sequence 1 97 editing a sequence 1 99 generating files in a loop counter example 1 115 in depth sequencing information 1 104 inserting a command 1 100 limit test example sequence 1 117 loading a sequence from a disk 1 103 loop counter example sequence 1 114 modifying a command 1 100 naming files generated by a sequence 1 102 printing a sequence 1 104 purging a sequence from a disk 1 103 running a sequence 1 99 s
106. move the active marker to the minimum point on the measurement trace 1 39 Making Measurements Using Markers Figure 1 29 Example of Searching for the Minimum Amplitude Using a Marker CHL S21 log MAG 1 dB REF 45 dB 1 75 507 dB 144 658 ede MHz I zl MARKER 1 144 85 MHz LI __ CENTER 134 808 BBA MHz SPAN 38 2808 BAG MHz aw000052 Searching for a Target Amplitude 1 Press Marker Search to access the marker search menu 2 Press SEARCH TARGET to movethe active marker to the target point on the measurement trace 3 If you want to change the target amplitude value default is 3 dB press TARGET and enter the new value from the front panel keypad You may also press Marker Search TARGET VALUE toenter the new value 4 f you want to search for multiple responses at the target amplitude value press SEARCH LEFT and SEARCH RIGHT Figure 1 30 Example of Searching for a Target Amplitude Using a Marker CH1 Spy log MAG i8 dB REF 45 dB 1 25 01 dB CH1 Sg og MAG iB dB REF 45 dB 1 25 007 dB CIT 126 451 343 MHz TARGET value 25 dB TARGET VALUE 25 dB CENTER 134 288 9028 MHz SPAN 38 8080 809 MHz pg6230 CENTER 134 000 GBB MHz SPRN 38 8000 AAA MHz 1 40 Making Measurements Using Markers Searching for a Bandwidth
107. one direction 6 Determine the offset delay of the calibration short by examining the define standard menu see Define Standard Menus on page 7 58 7 Subtract the offset delay of the short determined in step 6 from the delay of thethru and the short in one direction determined in step 5 Theresult is electrical delay of the thru This valueis used in the next procedure 6 75 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Remove the Adapter When the two sets of error correction files have been created now referred to as calibration sets the A3 adapter may be removed l Press MORE ADAPTER REMOVAL to display the following menu HELP ADAPT REMOVAL This Help softkey provides a quick reference guide to using the adapter removal technique RECALL CAL SETS ADAPTER DELAY ADAPTER COAX ADAPTER WAVEGUIDE REMOVE ADAPTER 2 Press RECALL CAL SETS todisplay RECALL CAL PORT 1 and RECALL CAL PORT2 RECALL CAL SETS also displays the internal or external if internal not used disk file directory NOTE In the following two steps calibration data is recalled not instrument states 3 From the disk directory choose the file associated with the port 1 error correction then press RECALL CAL PORT 1 4 When this is complete choose the file for the port 2 error correction and press RECALL CAL PORT2 5 When complete press RETURN 6 Enter the value of adapter A3 electrical delay by pressi
108. order to usetheL RM technique the calibration standards characteristics must be entered intothe analyzer s user defined calibration kit Thefollowing steps show you how to define a calibration kit to utilize a set of LRM LINE REFLECT MATCH standards This example LRM kit contains the following e zerolength LINE e flush short for the REFLECT standard 0 second offset e 50ohmtermination for the MATCH infinite length line NOTE LRM with a zero length line is sometimes referred toas TRM THRU REFLECT MATCH Modify the Standard Definitions 1 Press the following keys to start modifying the standard definitions CAL KIT MODIFY DEFINE STANDARD 2 Toselect a short press x1 In this example the REFLECT standard is a SHORT 3 Press the following keys SHORT MODIFY STD DEFINITION SPECIFY OFFSET OFFSET DELAY 0 STD OFFSET DONE STD DONE DEFINED 4 Todefinethe THRU LINE standard press DEFINE STANDARD DELAY THRU MODIFY STD DEFINITION SPECIFY OFFSET OFFSET DELAY 90 STD OFFSET DONE STD DONE DEFINED 5 To definethe LINE MATCH standard press DEFINE STANDARD LOAD 6 For the purposes of this example change the name of the standard by pressing MODIFY STD DEFINITION LABEL STD ERASE TITLE ifa previous title exists and then modify the name to MATCH 7 When thetitle area shows the new label press DONE STD DONE DEFINED 6 56 Calibrating for Increased Measurement Accuracy LRM Error Correction Ass
109. per year The service guide includes the measurement verification procedure Reference Plane and Port Extensions Usethe port extension feature to compensate for the phase shift of an extended measurement reference plane dueto such additions as cables adapters and fixtures after completing an error correction procedure or when there is no active correction Using port extensions is similar to using electrical delay However using port extensions is the preferred method of compensating for test fixture phase shift Table 5 2 explains the difference between port extensions and electrical delay Optimizing Measurement Results Increasing Measurement Accuracy Table 5 2 Differences between PORT EXTENSIONS and ELECTRICAL DELAY PORT EXTENSIONS ELECTRICAL DELAY Main Effect Theend of a cable becomes the test port plane for all S parameter measurements Compensates for the electrical length of a cable Set the cable s electrical length x 1 for transmission Set the cable s electrical length x 2 for reflection Measurements Affected All S parameters Only the currently selected S parameter Electrical Compensation I ntelligently compensates for 1 times or 2 times the cable s electrical delay depending on which S parameter is computed Only compensates for electrical length You can activate a port extension by pressing MORE PORT EXTENSIONS EXTENSIONS ON Then enter the delay to the r
110. plot m Choose PLOT GRAT ON if you want the graticule and the reference line to appear on your plot m Choose PLOT TEXT ON if you want all of the displayed text to appear on your plot This does not include the marker values or softkey labels m Choose PLOT MKR ON if you want the displayed markers and marker values to appear on your plot Figure 4 5 Plot Components Available through Definition Text Time Date mt j nd Marker Information Graticule Reference Line CH1 START 1 078 ns STOP 1 505 ns pa5167e Selecting Auto Feed Press AUTO FEED until the correct choiceis highlighted m Choose AUTO FEED ON if you want a page eject sent to the plotter or HPGL compatible printer after each time you press PLOT LY Choose AUTO FEED OFF if you want multiple plots on the same sheet of paper 4 13 Printing Plotting and Saving Measurement Results Defining a Plot Function NOTE The peripheral ignores AUTO FEED ON when you are plotting toa quadrant Selecting Pen Numbers and Colors Press MORE and select the plot element where you want to change the pen number For example press PEN NUM DATA and then modify the pen number The pen number selects the color if you are plotting to an HPGL 2 compatible color printer Press after each modification NOTE The following color assignments are valid for HPGL 2 compatible color printers only When using word processor or graphics presentation programs diffe
111. port is dedicated for normal copy device use printers or plotters f you choose PARALLEL GPIO the parallel port is dedicated for general purpose I O and cannot be used for printing or plotting Choose SERIAL if your plotter has a serial RS 232 interface and then configure the plot function as follows a Press PLOTTER BAUD RATE and enter the plotter s baud rate followed by x1 b Toselect the transmission control method that is compatible with your plotter press XMIT CNTRL transmit control handshaking protocol until the correct method appears L4 If you choose Xon Xoff the handshake method allows the plotter to control the data exchange by transmitting control characters to the network analyzer OV If you choose DTR DSR the handshake method allows the plotter to control the data exchange by setting the electrical voltage on one line of the RS 232 serial cable NOTE Because the DTR DSR handshake takes place in the hardware rather than the firmware or software it is the fastest transmission control method If You Are Plotting Measurement Results to a Disk Drive The plot files that you generate from the analyzer contain the H PGL representation of the measurement display The files will not contain any setup or formfeed commands CAUTION Do not mistakethe line switch for the disk eject button when you are removing the disk from the analyzer If the line switch is mistakenly pushed the instrument wil
112. printing parameters to default values 4 7 resolution 3 32 range resolution 3 34 response resolution 3 32 response calibration 2 26 error correction for reflection measurements 6 12 error correction for transmission measurements 6 14 magnitude 1 7 resolution 3 32 response and isolation calibration 7 54 response and isolation error correction for reflection measurements 6 19 response calibration 7 54 restarting a calibration 6 5 reverse isolation 1 63 reviewingthelimit line segments 1 77 RF feedthrough 2 45 RF frequency range 2 21 using the calculation 2 21 using the mixer measurement diagram 2 15 2 21 RF range power meter calibration 2 21 RF defining 2 7 ripple limit testing 1 80 1 90 ripple limits editing 1 83 1 85 running the test 1 85 1 90 setting 1 80 1 83 ripple test absolute value 1 88 displaying limits 1 86 displaying values 1 87 frequency bands 1 82 margin value 1 90 message color 1 86 starting and stopping 1 85 running a bandwidth test 1 93 1 96 running a limit test 1 77 running a sequence 1 99 running the ripple limits test 1 85 1 90 S 11 and S22 one port calibration 7 55 S2P data format 4 40 safety considerations 8 5 before applying power 8 5 compliance with German FTZ emissions requirements 8 8 compliance with German noise requirements 8 8 general 8 7 Safety earth ground 8 5 servicing 8 6 safety earth ground 8 5 safety symbols 8 4 sa
113. s O m 11 5 151 CH4 START S ns STOP 5 ns CH1 START 5 ns STOP 5 ns a Short Circuit b Short Circuit at the End of a 3 dB Pad pg6194 c 3 26 Making Time Domain Measurements Windowing Windowing The analyzer provides a windowing feature that makes time domain measurements more useful for isolating and identifying individual responses Windowing is needed because of the abrupt transitions in a frequency domain measurement at the start and stop frequendies The band limiting of a frequency domain response causes overshoot and ringingin thetime domain response and causes a non windowed impulse stimulus to have a sin kt kt shape where k z frequency span and t time see Figure 3 22 This has two effects that limit the usefulness of the time domain measurement Finiteimpulse width or rise time Finite impulse width limits the ability to resolve between two closely spaced responses The effects of the finite impulse width cannot be improved without increasing the frequency span of the measurement see Table 3 3 Figure 3 22 Impulse Width Sidelobes and Windowing A m d IMPULSE WIDTH WINDOWING AMPLITUDE SIDELOBES pg665d Sidelobes The impulse sidelobes limit the dynamic range of the time domain measurement by hiding low level responses within the sidelobes of higher level responses The effects of sidelobes can be improved by windowing see Ta
114. same power range setting of that single port An error message will be displayed if you enter two power levels that do not fall within the same power range 6 59 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal Calibrating Using Electronic Calibration ECal This section describes Electronic Calibration ECal Usethe following steps to perform the calibration 1 Set up the measurement for which you are calibrating Refer to Set Up the M easurement uF WN Connect the ECal equipment Refer to Connect the ECal Equipment on page 6 61 Select the ECal options Refer to Select the ECal Options on page 6 62 Perform the calibration Refer to Perform the Calibration on page 6 64 Perform the confidence check Refer to Perform the Confidence Check on page 6 67 Set Up the Measurement 1 Press Preset 2 Select the type of measurement you want to make M If you want to make a reflection measurement on PORT 1 in the forward direction 513 leave the instrument default setting or press Refl FWD S11 A R If you want to make a transmission measurement in the forward direction S21 press Trans FWD S21 B R If you want to make a transmission measurement in the reverse direction S15 press Trans REV S12 A R If you want to make a reflection measurement on PORT 2 in the reverse direction S22 press Refl REV S22 B R 3 Set any other measu
115. seconds after disconnecting the plug from its power supply For continued protection against fire hazard replace line fuse only with same type and rating 115V operation T 5A 125 V UL CSA 230V operation T 4A H 250V IEC The use of other fuses or material is prohibited General WARNING WARNING CAUTION CAUTION WARNING Safety and Regulatory Information Safety Considerations To prevent electrical shock disconnect the analyzer from mains before cleaning Use a dry cloth or one slightly dampened with water to clean the external case parts Do not attempt to clean internally If this product is not used as specified the protection provided by the equipment could be impaired This product must be used in a normal condition in which all means for protection are intact only This product is designed for usein Installation Category I1 and Pollution Degree 2 per IEC 1010 and 664 respectively VENTILATION REQUIREMENTS When installingthe product in a cabinet the convecti on into and out of the product must not be restricted The ambient temperature outside the cabinet must be less than the maximum operating temperature of the product by 4 C for every 100 watts dissipated in the cabinet If the total power dissipated in the cabinet is greater that 800 watts then forced convection must be used Install the instrument according to the enclosure protection provided This instrument does not protect against the ingress of wa
116. sequences are finished you should have a result as shown in Figure 2 23 Figure 2 23 Example Fixed IF Mixer Measurement CH1 B log MAG 2 dB REF 20 dB START 100 000 000 MHz STOP 100 000 000 MHz The displayed trace represents the conversion loss of the mixer at 26 points Each point corresponds to one of the 26 different sets of RF and LO frequencies that were used to create the same fixed IF frequency 2 31 Making Mixer Measurements Phase or Group Delay Measurements Phase or Group Delay Measurements For information on group delay principles refer to Setting the Electrical Delay on page 1 37 Phase Measurements When you are making linear measurements you must provide a reference for determining phase by splitting the RF source power and send part of the signal into the reference channel This does not work for frequency offset measurements since the source and receiver are functioning at different frequencies To provide a reference signal for the phase measurement you need a second mixer This mixer is driven by the same RF and LO signals that are used to drive the mixer under test ThelF output from the reference mixer is applied tothe reference R channel of the analyzer Phase Linearity and Group Delay Group delay is the rate of change of phase through a device with respect to frequency do dw Traditionally group delay has been used to describe the propagation
117. stepped list mode the LIST FREQ SWEPT softkey also provides access tothe segment menu H owever swept list mode expands the way segments can be defined Refer to the following information on how to enter or modify the list segments Swept Edit List Menu The EDIT LIST softkey within the sweep type menu provides access to the edit list menu Thefunction of this menu is the same as in the stepped list mode Swept Edit Subsweep Menu Usingthe EDIT or ADD softkey within the edit list menu will display the edit subsweep menu This menu lets you select measurement frequencies arbitrarily Using this menu it is possible to define the exact frequencies to be measured on a point by point basis at specific power levels and IF bandwidth settings The total sweep is defined with a list of subsweeps 7 17 Operating Concepts Sweep Types The frequency subsweeps or segments can be defined in any of the following terms start stop number of points power l F BW Sstart stop step power l F BW e center span number of points power l F BW center span step power l F BW See Setting Segment Power and Setting Segment IF Bandwidth on page 7 18 for information on how to set the segment power and IF bandwidth The subsweeps may be entered in any particular order but they cannot overlap The analyzer sorts the segments automatically and lists them on the display in order of increasing start frequency even if they are entered in center span format
118. table Raw offsets may be turned on or off individually for each channel They follow the channel coupling For dual channel operation raw offsets should be turned off for each channel if the channels are uncoupled Spur avoidanceis always coupled between channels therefore both channels are turned on or off at the same time NOTE Both functions must be turned off to realizethe recall time savings Refer to Specifications and Characteristics chapter in the reference guide for examples of recall state times with the following functions on or off raw offsets spur avoidance and blank display Using blank display may speed up recall times Understanding Spur Avoidance In the 400 MHz to 3 GHz range where the source signal is created by heterodyning two higher frequency oscillators unwanted spurious mixing products from the source may be present at the output These spurs can become apparent in filter measurements when filters have greater than 80 dB rejection Spur avoidance slightly moves the frequency of both oscillators such that the source frequency remains the same but the spurious mixing products shift out of the measurement receiver range The calculation of the exact frequency points where the shifting must occur stored in the sampler offset table increases the ti me needed to change or recall instrument states Selecting SPUR AVOID OFF and RAW OFFSET OFF eliminates this calculation Optimizing Measurement Results Reducing Rec
119. that can be used for effective noise reduction is the marker statistics function which computes the average value of part or all of the formatted trace Optimizing Measurement Results Reducing Receiver Crosstalk Reducing Receiver Crosstalk To reduce receiver crosstalk you can dothe following Perform a response and isolation measurement calibration Set the sweep to the alternate mode Alternate sweep is intended for measuring wide dynamic range devices such as high pass and bandpass filters This sweep mode removes a type of leakage term through the device under test from one channel to another To set the alternate sweep press MORE ALTERNATE AandB Refer to Frequency Response and Isolation Error Corrections on page 6 17 5 16 Optimizing Measurement R esults Reducing Recall Time Reducing Recall Time To reduce time during recall and frequency changes the raw offset function and the spur avoidance function can be turned off Toturn these functions off press CONFIGURE MENU RAWOFFSET OFF SPUR AVOID OFF Theraw offset function is normally on and controls the sampler and attenuator offsets The spur avoidance function is normally on and generates values as part of the sampler offset table The creation of this table takes considerable time during a recall of an instrument state To savetime at recalls and during frequency changes both functions should be turned off This will avoid generating the sampler offset
120. the current active calibration set in use This process uses up an internal memory register The calibration in this register is not the calibration created by adapter removal rather it is a scratch calibration You may wish to delete the register or re save the new calibration in this register step 14 14 Press Save Recall SELECT DISK INTERNAL MEMORY RETURN and SAVE STATE You can now remove the adapter from the test setup and insert the DUT 6 44 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Figure 6 17 Calibrated Measurement NETWORK ANALYZER V 7 ee FES Reference Reference Port 1 Port 2 pa5101e Verify the Results Sincethe effect of the adapter has been removed it is easy to verify the accuracy of the technique by simply measuring the adapter itself Because the adapter was used during the creation of the two cal sets and the technique removes its effects measurement of the adapter itself should show the S parameters f unexpected phase variations are observed this indicates that the electrical delay of the adapter was not specified within a quarter wavelength over the frequency range of interest To correct this recall both cal sets sincethe data was previously stored to disk change the adapter delay and press REMOVE ADAPTER Your analyzer s programmer s guide contains an example program that demonstrates the adapter removal process over GPIB 6 45
121. the data strobe pin 16 selects the printer pin 17 resets the printer pins 18 25 are ground Electrical specifications for TTL high e volts H gt 2 7 volts V e current 20 microamps uA Electrical specifications for TTL low e volts L x 0 4 volts V current 0 2 milliamps mA 1 107 Making Measurements Using Test Sequencing Figure 1 76 Parallel Port Input and Output Bus Pin Locations in GPIO Mode 432 10 PARALLEL IN BITS a e eeeeooooe 1 25 uibs 0 2 5 u 5 6 7 PARALLEL OUT BITS 1 108 pg6129d Making Measurements Using Test Sequencing Test Set Interconnect Control Figure 1 77 Test Set Interconnect Pin Designations TEST SET I O INTERCONNECT GROUND TESTSET 5 I O BITSl 4 GROUND HIGH JE GROUND FORWARD REVERSE GROUND LIMIT TEST TEST SEQUENCE TTL OUT 22V pab176e Control of the external switch 8762B Option T24 can be done through the test set interface on the rear panel of the analyzer Pin 22 TTL 1 onthe TEST SET I O INTERCONNECT connector is a TTL line that changes from TTL high to TTL low when changing TTL I O FWD from 7 to 6 Refer to Figure 1 77 To change from 7 to 6 press the following sequence e Pres TTLI O TTLOUT TESTSET I O FWD 6 x1 Changing the switch state back to the standard mode requires a 7 to be entered in the TESTSET I O FWD Pin 1 on the external switch must be grounded I
122. the displayed menu refer to Modifying Calibration Kits on page 7 56 Toselect the correction type press CALIBRATE MENU FULL 2 PORT REFLECTION Connect a shielded open circuit to PORT 1 NOTE Include any adapters that you will have in the device measurement That is connect the standard to the particular connector where you will connect your DUT 6 29 Calibrating for Increased Measurement Accuracy Full Two Port Error Correction Figure 6 9 Standard Connections for Full Two Port Error Correction FOR REFLECTION FOR TRANSMISSION FOR ISOLATION E E oleae etetted p 1 0 Possible Open Short Load Open Short Load Adapters For S41 For 55 pa587e 6 To measure the standard when the displayed trace has settled press FORWARD OPEN The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the OPEN softkey after it measures the standard 7 Disconnect the open and connect a short circuit to PORT 1 8 To measure the device when the displayed trace has settled press FORWARD SHORT The analyzer measures the short circuit and underlines the SHORT softkey 9 Disconnect the short and connect an impedance matched load to PORT 1 10 To measure the standard when the displayed trace has settled press FORWARD LOAD select the type of load you are using and then press DONE LOADS when the analyzer has finished measuring the load
123. the first segment press ADD FREQUENCY and enter a frequency of a correction factor data point followed by the appropriate key kim Press LOSS and enter the power loss that corresponds to the attenuation of the directional coupler or power splitter at the frequency that you have entered in the previous step Complete the power loss entry by pressing DONE 6 35 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration NOTE Remember to subtract the through arm loss from the coupler arm loss before entering it into the power loss table to ensure the correct power at the output of the coupler 4 Repeat the previous two steps to enter up to 12 frequency segments depending on the required accuracy You may enter multiple segments in any order becausethe analyzer automatically sorts them and lists them on the display in increasing order of frequency If you only enter one frequency segment the analyzer assumes that the single value is valid over the entire frequency range of the correction 5 After you have entered all the segments press DONE 6 Press PWRMTR CAL PWR LOSS ON to activate the power loss compensation Using Sample and Sweep Correction Mode You can use the sample and sweep mode to correct the analyzer output power and update the power meter correction data table during the initial measurement sweep Because the analyzer measures the actual power at each frequency point during the in
124. the test device displayed in near real time Response values measured on the vertical axis now appear separated in time or distance providing valuable insight into the behavior of the test device beyond simple frequency characteristics With Option 010 the analyzer can transform frequency domain data tothe time domain or time domain data tothe frequency domain NOTE Theanalyzer can be ordered with Option 010 or the option can be added at a later date Thetransform used by the analyzer resembles time domain reflectometry TDR measurements TDR measurements however are made by launching an impulse or step into the test device and observing the response in time with a receiver similar to an oscilloscope n contrast the analyzer makes swept frequency response measurements and mathematically transforms the data into a TDR like display Figure 3 1 illustrates the frequency and time domain reflection responses of a test device The frequency domain reflection measurement is the composite of all the signals reflected by the discontinuities present in the test device over the measured frequency range 3 3 Making Time Domain Measurements Introduction to Time Domain Measurements Figure 3 1 Device Frequency Domain and Time Domain Reflection Responses CH1 S44 log MAG 10 d8 AEF 40 dB 4 36 921 dB CHi S44 lin MAG 10 mU REF OU 4 35 761 mu ta 18 dos ns 7 14 925 393 MHz Cor cor MAR 1B 5 4
125. the time axis indicates the propagation delay or electrical length of the device The markers read the electrical delay in both time and distance The distance can be scaled by an appropriate velocity factor as described in Time Domain Bandpass M ode on page 3 12 Interpreting the Low Pass Step Transmission Response Vertical Axis In thereal format the vertical axis displays the transmission response in real units for example volts For the amplifier examplein Figure 3 15 if the amplifier input is a step of 1 volt the output 2 4 nanoseconds after the step indicated by marker 1 is 5 84 volts In thelog magnitude format the amplifier gain is the steady state value displayed after theinitial transients die out Measuring Separate Transmission Paths through the Test Device Using Low Pass Impulse Mode The low pass impulse mode can be used to identify different transmission paths through a test device that has a response at frequencies down to dc or at least has a predictable response above the noise floor below 30 kHz For example usethe low pass impulse mode to measure the relative transmission times through a multi path device such as a power divider Another example is to measure the pulse dispersion through a broadband transmission line such as a fiber optic cable Both examples are illustrated in Figure 3 16 The horizontal and vertical axes can be interpreted as already described in Time Domain Bandpass M ode on page 3 12
126. these files are rolled up into a single instrument state so the analyzer shows only the FileXX part of the name without an extension The file description will say ISTATE followed by parentheses with letters in them such as CDG These letters are explained on the bottom of the analyzer screen and indicate some of what is included in that instrument state In this example the state includes the Calibration Array Data and Graphics The only way to see all the file extensions previously described is to save the instrument state to a disk and view the file structure on an external computer Saving Time Gated Frequency Data Internal data processing is done sequentially beginning with raw data and ending with error correction and all formatting applied The time domain processing occurs near the end of this processing chain so data showing the effects of time domain processing is only available in formatted arrays 4 48 Printing Plotting and Saving Measurement Results Saving Measurement Results Differences between Raw Data and Format Arrays The following discussion explains the data processing flow in the network analyzer This information is very important if you will be utilizing data from your analyzer for use in computer applications such as spreadsheets word processing programs etc Refer to Figure 4 13 on page 4 38 The analyzer receives data from its A B and R or Aux in inputs Notice the three highlighted blocks
127. to its original value and the analyzer will automatically interpolate this calibration 6 Make surethe power meter calibration is on When the power meter calibration is on PC is displayed at the left edge of the display Refer to Figure 2 15 on page 2 17 for an example 2 13 Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode 7 From the front panel of the analyzer set the desired IF start and stop frequencies by pressing INSTRUMENT MODE FREQ OFFS MENU Note that these are the example IF start and stop frequencies Enter the IF start and stop frequencies for your measurement instead 8 Tocalibrate the R channel over thelF range connect the equipment as shown in Figure 2 11 Figure 2 11 Connections for R Channel Calibration NETWORK ANALYZER 550 MHz Splitter Low Pass Filter 10 dB 50 2 Load mixer setup calr optO11 NOTE An error message will be displayed while the R In port is disconnected Ignore this error message until R In port is reconnected 9 Press Cal CALIBRATE MENU RECEIVER CAL 0 TAKE RCVR CAL SWEEP T The low pass filter is required to limit the range of frequencies passed into the R channel input port The filter is selected to pass the IF frequencies for the measurement but prevent the LO feedthrough and unwanted mixer products from confusing the phase lock loop operation T A pad is used to isolate the filter and improve the IF port match for the mixer Onc
128. to position the gate markers around the desired portion of the time domain trace 3 36 4 Printing Plotting and Saving Measurement Results 4 1 Printing Plotting and Saving Measurement Results Using This Chapter Using This Chapter This chapter contains instructions for the following tasks 4 2 Printing or plotting your measurement results L D DL D D DL D DL DL D DL DO DL DL D D D O O O Configuring a print function Defining a print function Printing one measurement per page Printing multiple measurements per page Configuring a plot function Defining a plot function Plotting one measurement per page using a pen plotter Plotting multiple measurements per page using a pen plotter Plotting a measurement to disk To view plot files on a PC Outputting plot files from a PC to a plotter Outputting plot files from a PC to an HP GL compatible printer Outputting single page plots using a printer Outputting multiple plots to a single page using a printer Plotting multiple measurements per page from disk Titling the displayed measurement Configuring the analyzer to produce a time stamp Aborting a print or plot process Printing or plotting the list values or operating parameters Solving problems with printing or plotting Saving and recalling instrument states DOUC CC O O oO Saving an instrument state Saving measurement results Re saving an instrument state Deleting a file Renaming a file Re
129. tothis pin TESTSET I O Bit 2 most significant bit 5 V when TESTSET I O has values of 4 5 6 or 7 Otherwise bit is TTL low Ground NC 22 Volts NC NC Same as Limit Test output BNC connector Ground NC NC Ground TESTSET 1 O Bit 0 least significant bit 5 V when TESTSET I O has values of 1 3 5 or 7 Otherwise bit is TTL low TESTSET I O Bit 1 middle bit 5 V when TESTSET 1 O has values of 2 3 6 or 7 Otherwise bit is TTL low Lremtrig TTL low when TEST SET I O pins are valid This bit can be used to latch these values NC 1 110 Making Measurements Using Test Sequencing TTL Out Menu The TTL OUT softkey provides access tothe TTL out menu This menu allows you to choose between the following output parameters of the TTL output signal TTL OUT HIGH TTL OUT LOW END SWEEP HIGH PULSE END SWEEP LOW PULSE The TTL output signals are sent to the sequencing BNC rear panel output Sequencing Special Functions Menu This menu is accessed by pressingthe SPECIAL FUNCTIONS softkey in the Sequencing menu This menu provides access to the decision making menu and the more special functions menu It also contains the peripheral GPIB address and titling wait x pause and marker CW functions Sequence Decision Making Menu This menu is accessed by pressing the DECISION MAKING softkey in the Sequencing Special Functions menu Decision making functions are explained in more detail
130. view the magnitude and the phase of the active marker The magnitude values appear in units and the phase values appear in degrees Choose LOG MKR if you want to view the logarithmic magnitude and the phase of the active marker The magnitude values appear in dB and the phase values appear in degrees e Choose Re Im MKR if you want to view the real and imaginary pair where the complex data is separated into its real part and imaginary part The analyzer shows the real part as the first marker value M cos and the second value is the imaginary part M sin where M magnitude Figure 1 20 Example of a Log Marker in Polar Format CHi Sj i U FS 2 2 762 dB 75 741 9 398 501 MHz a cama nin 948 d k AT __V 7104818428 MARKER ut TQS i GHz pa em s 442 foasot Maz ss A wa a x 4 y x 4 a gt NON va START 930 808 MHz STOP amp 099 000 820 MHz aw000037 1 32 Making Measurements Using Markers To Use Smith Chart Markers For greater accuracy when using markers in the Smith chart format activate the discrete marker mode Press MKR MODE MENU MARKERS DISCRETE To use Smith chart format 1 Press SMITH CHART 2 Press MARKER MODE MENU SMITH MKR MENU andturn the front panel knob or enter a value from the front panel keypad to read the resistive and reactive components of the complex impedance at any point along the trace This is the default Smith chart marker The marker annotation tell
131. what you can save to the analyzer s internal memory 4 34 widening the system bandwidth 5 11 windowing 3 27
132. 0 15 5 6538 20 167 2 0132 10 241 18 555 26 18 34 743 42 682 50 854 58 917 67 008 74 862 83 048 20 15 20 377 20 387 20 112 20 198 20 19 20 223 20 21 20 188 20 208 20 256 1 6658 10 029 17 96 26 061 34 195 42 289 50 407 58 436 66 587 74 616 82 874 attenuator 36 188 33 974 31 287 29 427 24 719 25 102 27 582 33 828 44 184 36 893 30 385 123 52 40 215 61 778 153 37 137 83 81 096 25 509 35 237 62 912 35 384 74 001 Printing Plotting and Saving Measurement Results Saving Measurement Results Saving in Textual CSV Form Textual measurement results can be saved in a comma separated value CSV format and imported into a spreadsheet application Additional information is also saved as a preamble to the measurement results The saved information includes Network analyzer model number and firmware version Date the file was saved Type of measurement being done Start and stop frequencies Sweep time Port power IF bandwidth Channel number Number of points Format The frequency or time and the real and imaginary measurement values for each of points measured Press Save Recall SAVE FILE FORMATS Makesurethat TEXT FMT CSV is displayed Makesurethat FILETYPE TEXT is underlined If it is not underlined press the softkey so that TEXT is underlined Insert a 3 5 inch floppy disk in the network analyzer s disk dri
133. 1 u7 216 dB hp 1300 GHA 1 Cor V Dp START 300 000 MHz STOP 3 000 000 MHz To Plot Measurements in Page Quadrants 1 2 Define the plot as explained in Defining a Plot Function on page 4 13 Press Copy SEL QUAD Choose the quadrant where you want your displayed measurement to appear on the hardcopy The selected quadrant appears in the brackets under SEL QUAD Figure 4 11 Plot Quadrants CH S21 log MAG 1 dB REF 20 dB CH S2 log MAG 1 dB REF 20 dB hp THANSWIBSION RESPQNSE qALIBRATION Ap FULL 2 PoRT ALIBAATION Cor Cor E aesti are wa Lh VN 1 START 300 000 MHz STOP 3 000 000 MHz START 300 000 MHz STOP 3 000 000 MHz CH S21 log MAG 10 db REF 40 dB 2 11821 dB CH S21 log MAG 10 db REF 40 dB 61 721 dB hp sf ns pe T9p a cor p cor MARKER Y MARKER 65 6 ns 1 9732 us Nd ssp u lA of of 4 CH1 CENTER 1 s SPAN 2 ps CH CENTER 1 ps SPAN 2 ps 4 28 ph647c pg65e Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page from Disk 4 Press PLOT Theanalyzer assigns the first available default filename fo
134. 1 Exe Stam Exe B JESF Esp SLE e ERF al ETF ETR o fSuw Epr Su E UM FoF Esc 12M XR S ERF Etp 12A Stim EpF S22M EDR Soim Exe Stam Exg Esp 1 Esp Ete ELR L ERF ERR Etf ETR Soom Epr m Ye S21M ExEN Stom Exr _ C E SF ELR l RR ETF ETR M 522A Stim Ep a Soim Exe Stam Exe 1 Es EsR ELF ELR E ERF el ETF ETR pg6128d How Effective Is Accuracy E nhancement In addition to the errors removed by accuracy enhancement other systematic errors exist dueto limitations of dynamic accuracy test set switch repeatability and test cable stability These combined with random errors also contribute to total system measurement uncertainty Therefore after accuracy enhancement procedures are performed residual measurement uncertainties remain The uncorrected performance of the analyzer is sufficient for many measurements H owever the next three illustrations show the improvements that can be made in measurement accuracy by using a more complete calibration routine See Figure 7 40 Figure 7 41 and Figure 7 42 7 51 Operating Concepts Measurement Calibration Figure 7 40a shows a measurement in log magnitude format with a response calibration only Figure 7 40b shows the improvement in the same measurement using an S11 one port calibration Figure 7 41a shows the measurement on a Smith chart with response
135. 1 shows sample displays of various calibration standards after calibration Electrical Offset Some standards have reference planes that are electrically offset from the mating plane of thetest port These devices will show a phase shift with respect to frequency Table 6 1 shows which reference devices exhibit an electrical offset phase shift The amount of phase shift can be calculated with the formula o 360 x f x c where f frequency electrical length of the offset c speed of light 3 x 109 meters second Fringe Capacitance All open circuit terminations exhibit a phase shift over frequency due to fringe capacitance Offset open circuits have increased phase shift because the offset acts as a small length of transmission line Refer to Table 6 1 6 6 Calibrating for Increased Measurement Accuracy Calibration Considerations Table 6 1 Calibration Standard Types and Expected Phase Shift Test Port Connector Type Standard Type Expected Phase Shift 7 mm Type N male Short 180 3 5 mm male 3 5 mm female 2 4 mm male 2 4 mm female Type N female 75Q Type N female Offset Short 180 360 xx C 7 mm Type N male Open 0 capitance 3 5 mm male 3 5 mm female 2 4 mm male 2 4 mm female Type N female 75Q Type N female Offset Open 360 x fx I C o o 0 P capitance Calibrating for Increased Measurement Accuracy Calibration Con
136. 100 to 500 MHz MIXER OUTPUT LO 1000 MHz MIXER INPUT MIXER MIXER OUTPUT NPUT MIXER INPUT Pal MHz 0 100 500 1000 1100 1500 IF Lo RF SOURCE SWEEPS FROM 1100 to 1500 MHz RECEIVER IS TUNED TO 100 to 500 MHz SOURCE SWEEPS UP IN FREQUENCY Example of a Downconverter with RF gt LO RF lt LO IF RF 400 to 100 MHz gt 600 to 900 MHz MIXER INPUT MIXER OUTPUT LO 1000 MHz MIXER INPUT MIXER MIXER INPUT MIXER OUTPUT INPUT f I I I I MHz 0 100 400 600 900 1000 iF RF LO SOURCE SWEEPS FROM 400 to 100 MHz RECEIVER IS TUNED TO 600 to 900 MHz SOURCE SWEEPS DOWN IN FREQUENCY Example of an Upconverter with RF lt LO RF lt LO RF IF 100 to 400 MHz MIXER OUTPUT 900 to 600 MHz MIXER INPUT LO 1000 MHz MIXER INPUT MIXER MIXER INPUT INPUT r 311 wd MIXER OUTPUT MHz 0 100 400 600 900 1000 E RF LO SOURCE SWEEPS FROM 900 to 600 MHz RECEIVER IS TUNED TO 100 to 400 MHz SOURCE SWEEPS DOWN IN FREQUENCY Example of a Downconverter with RF LO pb663d In standard mixer measurements the input of the mixer is always connected to the analyzer s RF source and the output of the mixer always produces thelF frequencies that are received by the analyzer s receiver H owever the ports labeled RF and IF on most mixers are not consistentl y connected to the analyzer s source and receiver ports respectively These mixer ports are switched depending on whether a down conver
137. 113 Tuned Receiver Mode The analyzer s tuned receiver mode allows you to tune its receiver to an arbitrary frequency and measure signal power This is only possibleif the signal you wish to analyze is at an exact known frequency Therefore the RF and LO sources must be synthesized and synchronized with the analyzer s ti me base Since the analyzer is not phaselocking in this configuration you can useit to measure conversion loss of a microwave mixer with an RF frequency range output Tuned receiver mode also increases dynamic range Broadband techniques like diode detection have a high noise floor while narrow band techniques like tuned receivers are much less suscepti ble to noise Sequence 1 Setup The following sequence initializes and calibrates the network analyzer It then initializes the two external sources prior to measurement This sequence includes putting the network analyzer into tuned receiver mode e setting up a frequency list sweep of 26 points performing a response calibration prompting the user to connect a mixer tothe test set up initializing a loop counter value to 26 addressing and configuring the two sources calling the next measurement sequence 1 Makethe following connections as shown in Figure 2 21 Set the GPIB address of the external RF source to 19 and the external LO source to 21 2 Confirm that the external sources are configured to receive commands in the SCPI programming language an
138. 12 B R SEL QUAD RIGHT LOWER PLOT DONE SEQ MODIFY 4 Run the test sequence by pressing DO SEQUENCE SEQUENCE 1SEQ1 4 19 Printing Plotting and Saving Measurement Results To View Plot Files on a PC To View Plot Files on a PC Plot files can be viewed and manipulated on a PC using a word processor or graphics presentation program Plot files contain a text stream of HPGL Hewlett Packard Graphics Language commands I n order to import a plot file into an application that application must have an import filter for HPGL often called HGL Two such applications from the Lotus suite of products are the word processor Ami Pro and the graphics presentation package Freelance Graphics Additionally a utility is available to convert plot files to PCX format so they can be used in additional PC applications NOTE Lotus applications are not supported by Hewlett Packard The following procedures are provided for informational use only Other applications or other versions of the same application may function differently When viewed in such programs the color and font size of the plot may vary from the output of an HPGL 2 compatible color printer The following table shows the differences between the color assignments of HPGL 2 compatible printers and Lotus applications Also refer to Selecting Pen Numbers and Colors on page 4 14 Table 4 6 Color Assignment Differences between HPGL 2 Compatible Printers and Lotus Applications
139. 1250 MHz 0 6 ns 2 32 Making Mixer Measurements Phase or Group Delay Measurements Set the LO source to the desired CW frequency of 1000 M Hz and power level to 13 dBm 2 Initialize the analyzer by pressing Preset Set the analyzer s LO frequency to match the frequency of the LO source by pressing INSTRUMENT MODE FREQ OFFS MENU LO MENU FREQUENCY CW From the front panel of the analyzer set the desired receiver frequency and source output power by pressing 0 PWR RANGE MAN Connect the instruments as shown in Figure 2 24 placing a broadband calibration mixer ZF M 4 between PORT 1 and PORT 2 CAUTION To prevent connector damage use an adapter part number 1250 1462 as a connector saver for R CHANNEL IN 2 33 Making Mixer Measurements Phase or Group Delay Measurements Figure 2 24 Connections for a Group Delay Measurement NETWORK ANALYZER 550 MHz Low Pass Filter 550 MHz Low Pass Filter 10 dB 10 dB Calibration Mixer Reference Mixer External LO Source Converter Under Test HEH pa551e 6 To select the converter type and a high side LO measurement configuration press INSTRUMENT MODE FREQ OFFS MENU DOWN CONVERTER RF lt LO FREQ OFFS ON 7 To view the measurement results on the analyzer s display press INSTRUMENT MODE FREQ OFFS MENU VIEW MEASURE 8 To select the format type press DELAY 9 To make a response error correction press B R CAL
140. 14 Customizing theFour Channel Display a4d4 13g SERA YER ERAEAEEEZEPRE R ERR S 1 17 Using Memory Traces and Memory Math Functions sees eee 1 19 Blanking Me DISpISV usqcbi t obee ES bdo PR Rkce g whe RC ee CR ECCE EROR FACE 1 21 Aqusting the Colors or the DISDIay ixiessekestexaadXaerbxarriXieik amp derXdeubEXe 1 22 Siig Markl ea iso d EROR E T REO CP RERURGRERT PN Tele iid bat bes IPIE AR E PRO RE 1 24 To Use Continuous and Discrete Markers 0 0000 cece eee eee 1 24 To Acad vateDisplay Marker ici cs ieiicew cde heedeia iE RIRE LORAN 1 25 To Move Marker Information Off the Grids 0200 c eee ees 1 26 Toss Data A MarkG Ss 22484 cce0etae tii oibeiet iol eteteesi bed eeeetiagawss 1 28 TOCAVA a Fixed MAKE fdr cece a REX TEX RESO oO Se4 RIS ee TeA ERs eR Dede He 1 29 To Couple and Uncouple Display Markers 00 0c eee ees 1 31 Tellse Polar Format Markers 423 xe vaudu ihe de YXd P dw eae ho bE eS Ge MRE 1 32 To Usesmith Chart Markers acieiRERFERAGPREE YR eset eb ied da eh E EPRidu dees 1 33 To Set Measurement Parameters Using Markers leere 1 34 Setungthe CW Frequency icceses om shed por ewe eedn ieee REG EHE ER REICH ORER ET Ai 1 38 Te Search for a Spec Amplitude iu saxa irc x Xen bk XXn ORE ROL epp RR 1 39 To Calculate the Statistics of the Measurement Data 200 0c eee eens 1 42 Measuring Electrical Length and Phase Distortion 0200 cece aee 1 43 Measuring Electrical LENG
141. 21 Making Mixer Measurements High Dynamic Range Swept RF IF Conversion Loss 3 Perform a one sweep power meter calibration over the RF frequency range at 5 dB m PWRMTR CAL ONE SWEEP TAKE CAL SWEEP Perform the High Dynamic Range Measurement 1 Return the analyzer to the IF frequency range Press G n J 2 Makethe connections shown in Figure 2 19 3 Set theLO sourcetothe desired CW frequency of 1500 MHz and power level to 13 dBm Figure 2 19 Connections for a High Dynamic Range Swept IF Conversion Loss Measurement NETWORK ANALYZER 1000 MHz Low Pass Filter 10 dB Reference Mixer 300 MHz Low Pass Filter Reference Mixer External LO Source pa542e 4 Setthe analyzers LO frequency to match the frequency of the LO source by pressing INSTRUMENT MODE FREQ OFFS MENU LO MENU FREQUENCY CW 2 22 Making Mixer Measurements High Dynamic Range Swept RF IF Conversion Loss 5 Toselect the converter type and low side LO measurement configuration press RETURN DOWN CONVERTER RF gt LO FREQ OFFS ON In this low side LO down converter measurement the analyzer s source frequency range will be offset higher than the receiver frequency range The source frequency range can be determined from the following equation receiver frequency range 100 1000 MHz LO frequency 1500 MHz 21 6 2 5 GHz 6 Toview the conversion loss in the best vertical resolution press VIEW MEASURE Scale Ref AUTOSCA
142. 26 1 1997 A1 1998 EN 61326 1 1997 A1 1998 Standard Limit CISPR 11 1990 EN 55011 1991 Group 1 Class A IEC 61000 4 2 1995 A1998 EN 61000 4 2 1995 4kV CD 8kV AD IEC 61000 4 3 1995 EN 61000 4 3 1995 3 V m 80 1000 MHz IEC 61000 4 4 1995 EN 61000 4 4 1995 0 5 kV sig 1 kV power IEC 61000 4 5 1995 EN 61000 4 5 1996 0 5 kV L L 1 kV L G IEC 61000 4 6 1996 EN 61000 4 6 1998 3 V 0 15 80 MHz IEC 61000 4 11 1994 EN 61000 4 11 1998 1 cycle 10096 Safety IEC 61010 1 1990 A1 1992 A2 1995 EN 61010 1 1993 A2 1995 CAN CSA C22 2 No 1010 1 92 Supplementary Information The products herewith comply with the requirements of the Low Voltage Directive 73 23 EEC and the EMC Directive 89 336 EEC and carry the CE marking accordingly dd Greg Pfeiffer Quality Engineering Manager Santa Rosa CA USA 6 April 2000 For further information please contact your local Agilent Technologies sales office agent or distributor Safety and Regulatory Information Declaration of Conformity 8 10 Index Numerics 2 port error corrections performing 6 42 6 73 4 Param Displays softkey 1 18 A aborting a print or plot process 4 31 absolute ripple test value 1 87 1 88 absolute power 6 39 accuracy 1 58 accuracy and input power 7 88 accuracy enhancement 7 8 7 37 7 51 accurate measurements of electrically long devices cause of measurement problems 5 7 improving measurement results 5 7 activating ave
143. 4 sending the HPGL initialization sequence to the printer 4 24 sending the plot file to the printer 4 24 storing the exit HPGL modeand form feed sequence 4 24 storing the HPGL initialization sequence 4 23 P page quadrants plotting measurements in 4 28 parameters lower stopband 1 67 measurement 1 4 1 67 6 4 passband 1 67 upper stopband 1 68 pass control mode 7 78 passband parameters 1 67 PC interface unit 6 61 PC to view files on 4 20 pen numbers and colors selecting 4 14 pen plotter 4 17 4 18 plotting to 4 10 performance verification 5 5 performance verifying 7 64 performing 2 port error corrections 6 42 6 73 TRL calibration 6 54 TRM calibration 6 58 peripheral equipment required 7 5 per raw data arrays 7 8 phase linearity 2 32 measurements 2 32 tracking 2 36 phase distortion 1 43 1 45 phase format 7 24 phase or group delay measurements 2 32 Index 8 phaselinearity and group delay 2 32 phase measurements 2 32 places where you can save 4 34 plot aborting a process 4 31 plot files outputting from a PC toa plotter 4 22 outputting from a PC toan HPGL compatible printer 4 23 sending to the printer 4 24 to output 4 12 to view on a PC 4 20 plot function configuring 4 9 plotting to a pen plotter 4 10 plotting to an HPGL 2 compatible printer 4 9 plot function defining 4 13 choosing display elements 4 13 choosing plot speed 4 16 choosing scale 4 15 resetti
144. 460 mU hp 130 cud hp 5 5 ng xx Cor MARKER l1 i J15 ds T 1 0344 m ou eee Hi START 300 000 MHz STOP 3 000 000 MHz CH1 START O s STOP 10 ns pg643e The ripples in reflection coefficient versus frequency in the frequency domain measurement are caused by the reflections at each connector beating against each other One at a time loosen the connectors at each end of the cable and observe the response in both the frequency domain and thetime domain The frequency domain ripples increase as each connector is loosened corresponding to a larger reflection adding in and out of phase with the other reflections Thetime domain responses increase as you loosen the connector that corresponds to each response Interpreting the Bandpass Reflection Response Horizontal Axis In bandpass reflection measurements the horizontal axis represents the ti me it takes for an impulse launched at the test port to reach a discontinuity and return tothe test port the two way travel time In Figure 3 10 each connector is a discontinuity Interpreting the Bandpass Reflection Response Vertical Axis The quantity displayed on the vertical axis depends on the selected format The common formats are listed in Table 3 1 The default format is LOG MAG logarithmic magnitude which displays the return loss in d
145. 5 946 Sa2 MHz T 7 R1 346522 E M M M L 1 Ps CENTER 135 968 758 MHz SPAN 31 9062 500 MHz CENTER 132 992 O11 MHz SPRN 24 909 Q22 MHz pg6233 Setting the Center Frequency 1 Press and turn the front panel knob or enter a value from the front panel keypad to position the marker at the value that you want for the center frequency 2 Press MARKER CENTER to change the center frequency value to the value of the active marker 1 35 Making Measurements Using Markers Figure 1 24 Example of Setting the Center Frequency Using a Marker CHi Sg log MAG 20 dB REF 60 dB 1 35 423 dB CH1 S2 log MAG 20 dB REF 68 dB 1 36 281 dB 134 a ede MHz 134 dae Ode MHz at vd CENTER 106 748 326 MHz SPAN 176 427 8082 MHz CENTER 134 8000 O80 MHz SPAN 176 427 B Z MHz pg6234 Setting the Frequency Span You can set the span equal to the spacing between two markers If you set the center frequency before you set the frequency span you will have a better view of the area of interest 1 Press Marker AMODE MENU AREF 1 MARKER 2 2 Turn the front panel knob or enter a value from the front panel keypad to position the markers where you want the frequency span
146. 62 specifying offset menu 7 60 calibration kit saving a modified 7 65 calibration kits modifying 7 56 calibration routines 7 54 full two port calibration 7 55 response and isolation calibration 7 54 response calibration 7 54 11 and S22 one port calibration 7 55 TRL LRM two port calibration 7 55 calibration standards 6 5 calibration techniques improper 5 4 calibration measurement 7 37 Index 1 Index calibration receiver 6 15 calibration TRL LRM 7 66 calling the next measurement sequence 2 27 capabilities mixer measurement 2 3 capacitance fringe 6 6 cause of measurement problems 5 7 center frequency setting 1 35 changing sequence title 1 102 system bandwidth 5 15 changing the ripple limits color 1 87 channel coupling 7 10 channel position softkey 1 17 channel stimulus coupling 7 14 characteristics of the filter 1 66 characterizing a duplexer 1 49 definitions 1 49 procedure 1 49 characterizing microwave systematic errors 7 41 device measurement 7 45 one port error model 7 41 two port error model 7 46 choosing display elements 4 13 measurement parameters 1 4 plot speed 4 16 scale 4 15 chop sweep mode activating 5 12 CITIfile 4 40 clarifying type N connector sex 4 dearing a sequencefrom memory 1 101 color changing the ripple limits 1 87 ripple test message 1 86 color printer using 4 6 colors of the display adjusting 1 22 default 1 22 intensity
147. 7 customizing 1 17 viewing 1 14 measurement data dividing by the memory trace 1 20 subtracting memory trace viewing 1 20 memory math functions 1 19 memory trace viewing 1 20 memory traces 1 19 primary measurement dual channel mode with decoupled channel power 1 13 dual channel mode with decoupled sti mulus 1 13 primary measurement channels 1 12 viewing 1 12 ratio measurements in channel 1 and 2 to 1 20 display intensity 1 22 display markers coupling 1 31 uncoupling 1 31 display markers activating 1 25 display memory 1 19 7 9 display reference value setting display ripple test limits 1 86 display ripple test values 1 87 displayed measurement titling 4 30 displaying the bandwidth markers 1 94 displaying the bandwidth value 1 95 drift frequency 5 5 drift temperature 5 5 dual channel modewith decoupled power 1 13 dual channel modewith decoupled stimulus 1 13 dual channel operation 1 57 7 87 duplexer characterizing 1 49 dynamic range increasing 5 14 ECal 6 60 6 77 adapter removal calibration 6 71 6 77 calibration 6 60 6 70 confidence check 6 67 equipment 6 61 isolation calibration 6 63 manual thru 6 62 module information 6 66 options 6 62 service menu 6 69 edit limits menu 7 82 edit segment menu 7 82 editing a sequence 1 99 deleting commands 1 99 editing line segments 1 77 editing ripple limits 1 83 1 85 electrical length 1 43 offset 6 6 electric
148. 8 dB REF 59 dB YOUR MEASUREMENT TITLE GOES HERA m RECDEFGHIIKEMNO T 1 i CENTER 135 A80 888 MHz SPAN 52 008 880 MHz aw000029 CAUTION The NEWLINE and FORMFEED keys are not intended for creating display titles Those keys are for creating commands to send to peripherals during a sequence program 4 30 Printing Plotting and Saving Measurement Results Configuring the Analyzer to Produce a Time Stamp Configuring the Analyzer to Produce a Time Stamp You can set a clock and then activate it if you want the time and date to appear on your hardcopies 1 Press System SET CLOCK Press Press Press Press Press Press pr b p own de GM Om Press SET YEAR and enter the current year followed by x7 SET MONTH and enter the current month of the year followed x7 SET DAY and enter the current day of the month followed by x1 SET HOUR and enter the current hour of the day 0 23 followed by x1 SET MINUTES and enter the next immediate minute followed by x1 ROUND SECONDS when the current timeis exactly as you have set it TIME STAMP until TIME STAMP ON appears on the softkey label Aborting a Print or Plot Process 1 Press the key to stop all data transfer 2 If your peripheral is not responding press again or reset the peripheral 4 31 Printing Plotting and Saving Measurement Results Printing or Plotti
149. Bm 2 41 Making Mixer Measurements Isolation Example Measurements Isolation Example Measurements Isolation is the measure of signal leakage in a mixer Feedthrough is specifically the forward signal leakagetothelF port High isolation means that the amount of leakage or feedthrough between the mixer s ports is very small Isolation measurements do not use the frequency offset mode Figure 2 32 illustrates the signal flow in a mixer Figure 2 32 Signal Flow in a Mixer Example RF Feedthrough RF 0 IF LO TO RF Leakage LO Feedthrough pg6105d LO to RF Isolation LO to RF isolation is the amount the LO power is attenuated when it appears directly at the RF port 1 Initialize the analyzer by pressing Preset 2 To select the analyzer frequency range and source power press 0 This source sti mulates the mixer s LO port 3 To select a ratio B R measurement press B R 4 Makethe connections as shown in Figure 2 33 2 42 Making Mixer Measurements Isolation Example Measurements Figure 2 33 Connections for a Response Calibration NETWORK ANALYZER 20 dB pa563e 5 Perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU NOTE A full 2 port calibration will increase the accuracy of isolation measurements Refer to Chapter 5 Optimizing Measurement Results 6 Makethe connections as shown in Figure 2 34 CAUTION To get an accurate assessment of the LO IF isol
150. CT LETTER c Repeat the previous two steps to enter the rest of the characters in your title You can enter a title that has a maximum of 50 characters d Press DONE to complete the title entry Figure 1 6 Example of a Display Title CH1 Sg log MAG 180 dB REF 58 dB YOUR MEASUREMENT TITLE GOES HERA RI EUN m NEN T NN I CENTER 135 88 8BB MHz SPAN 58 008 880 MHz aw000029 CAUTION The NEWLINE and FORMFEED keys arenot intended for creating display titles Those keys are for creating commands to send to peripherals during a sequence program Making Measurements Using Display Functions Viewing Both Primary Measurement Channels In some cases you may want to view more than one measured parameter at a time Simultaneous gain and phase measurements for example are useful in evaluating stability in negative feedback amplifiers You can easily make such measurements using the dual channel display 1 To see channels 1 and 2 in the same grid press DUAL QUAD SETUP set DUAL CHAN on OFF toON and SPLIT DISP to 1X Figure 1 7 Example of Viewing Channel 1 and 2 Simultaneously CH1 S21 log MAG 10 dB REF 50 dB CH2 S24 phase 90 REF O tal PRm i Conr F Ed CENTER 134 000 000 MHz SPAN 50 000 000 MHz pa5108e 2 To view the measurements on s
151. Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Matched Adapters With this method you use two precision matched adapters which are equal To be equal the adapters must have the same match Zo insertion loss and electrical delay The adapters in most Agilent calibration kits have matched electrical length even if the physical lengths appear different Figure 6 18 Calibrating for Noninsertable Devices PORT 1 ia PORT 2 NON INSERTABLE DEVICE 1 TRANSMISSION CAL USING ADAPTER A PORT 1 ADAPTER PORT 2 A N REFLECTION CAL USING PORT 1 UAE TESS PORT 2 ADAPTER B LENGTH OF ADAPTERS MUST BE EQUAL w MEASURE DUT USING ADAPTER B PORT 1 DUT ADAPTER PORT 2 pg6136d To use this method refer to Figure 6 18 and perform the following steps 1 Perform a transmission calibration using the first adapter 2 Remove adapter A and place adapter B on port 2 Adapter B becomes the effecti ve test port 3 Perform a reflection calibration 4 Measurethetest device with adapter B in place The errors remaining after calibration with this method are equal to the differences between the two adapters that are used 6 46 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Modify the Cal Kit Thru Definition With this method it is only necessary to use a thru adapt
152. DUAL CHAN ON PHASE The channel 2 portion of Figure 1 4 shows the insertion phase response of the device under test The analyzer measures and displays phase over the range of 180 to 180 As phase changes beyond these values a sharp 360 transition occurs in the displayed data Making Measurements Measuring Magnitude and Insertion Phase Response Figure 1 4 Example Insertion Phase Response Measurement CH1 S21 log MAG 10 dB REF 50 dB 1_ 23 507 dB ta ENT 139 600 odo MHz PRm 7 Cor MARKER 1 1B9 5 MH phase REF o e 1 97 982 9 500 OQO MHz CENTER 134 000 000 MHz SPAN 50 000 000 MHz pa5107e The phase response shown in Figure 1 5 is undersampled that is there is more than 180 phase delay between frequency points If the A gt 180 incorrect phase and delay information may result Figure 1 5 shows an example of phase samples being with Ao less than 180 and greater than 180 Figure 1 5 Phase Samples A 90 A 7 A 200 A P A Y o 170 ACTUAL PHASE RESPONSE UNDER SAMPLED REGION INCORRECT PHASE AND DELAY pb6125d Undersampling may arise when measuring devices with long electrical length To correct this problem the frequency span should be reduced or the number of points increased until A is less than
153. Domain Measurements Making Reflection Response Measurements Making Reflection Response Measurements Thetime domain response of a reflection measurement is often compared with the time domain reflectometry TDR measurements Likethe TDR the analyzer measures the size of the reflections versus time or distance Unlikethe TDR the time domain capability of the analyzer allows you to choose the frequency range over which you would like to make the measurement 1 To choose the measurement parameters press Refl FWD S11 A R 2 Perform an Sj 1 port correction on PORT 1 Refer to Chapter 5 Optimizing Measurement Results for a detailed procedure 3 Connect your device under test as shown in Figure 3 7 Figure 3 7 Device Connections for Reflection Time Domain Example Measurement NETWORK ANALYZER Oo oooo a 0000 0000 ooo 009 og o0 og 00 00 pr o0 000 o e 0 Oo ADAPTER E CABLES ADAPTERS p 5 502 TERMINATION CABLES uide 4 To better view the measurement trace press Scale Ref AUTO SCALE Figure 3 8 shows the frequency domain reflection response of the cables under test The complex ripple pattern is caused by reflections from the adapters interacting with each other By transforming this data to the time domain you can determine the magnitude of the reflections versus distance along the cable Making Time Domain Measurements
154. E BAND and then use the lt 3 Jand X keys or the numerical keypad to select the desired frequency band Viewing the Ripple Value in Absolute Format When RIPL VALUE ABSOLUTE is Selected the absolute ripple value of the selected frequency band is displayed The absolute ripple value is the measured maxi mum level minus the measured minimum level within the frequency band This value is displayed in dB Figure 1 67 shows the rippletest with absolute ripple value displayed for Frequency Band 1 The B1 indicates that the ripple value displayed is for Frequency Band 1 Notice that Frequency Band 1 passes the ripple test It has an absolute ripple value of 1 675 dB while the maximum ripple value entered for Frequency Band 1 was 2 0 dB Thus even though the ripple test fails because of Frequency Band 3 the ripple passes in Frequency Band 1 1 88 Making Measurements Using Ripple Limits to Test a Device Figure 1 67 Filter Pass Band with Absolute Ripple Value for Band 1 Activated 2 Jun 2888 18 48 12 CHI 311 Log i dB REF 3 dB RIFLI FRIL B1 1 675 dH Frequency Band 1 Absolute Ripple Value START 100 000 000 GHz STOP 3 500 000 666 GHz pa5200e Viewing the Ripple Value in Margin Format When RIPL VALUE MARGIN is selected the margin by which the ripple value passed or failed is displayed The ripple value margin is the user defined
155. E S228521 where Ep effective directivity Eg effective reflection tracking E s effective source match E effective load match Ex effective crosstalk E effective transmission tracking S47 S parameters of the device under test The TRL Calibration Procedure Requirements for TRL Standards When building a set of TRL standards for a microstrip or fixture environment the requirements for each of these standard types must be satisfied Types THRU Zero length THRU Non zero length REFLECT Requirements No loss Characteristic impedance Zo need not be known 521751271 20 511752 70 Zo of the thru must be the same as the line If they are not the same the average impedance is used Attenuation of the thru need not be known If the thru is used to set the reference plane the insertion phase or electrical length must be well known and specified If a non zero length thru is specified to have zero delay the reference planeis established in the middle of the thru resulting in phase errors during measurement of devices Reflection coefficient r magnitude is optimally 1 0 but need not be known Phase of r must known and specified to within 1 4 wavelength or 90 During computation of the error model the root choice in the solution of a quadratic equation is based on the reflection data An error in definition would show up as a 180 error in the measured phase 7 71 Operatin
156. ERTURE S kW SPA Smo 118 kHz J f i i CENTER 134 088 098 MHz SPAN 2 9800 APA MHz aw000009 Group delay is calculated by dividing the phase difference between points by the frequency spacing Thus if n equals the number of points the number of phase difference values or frequency segments will be n 1 Thefirst data point is repeated sothat the total number of points remains n 1 48 Making Measurements Characterizing a Duplexer Characterizing a Duplexer This measurement example demonstrates how to characterize a 3 port device in this case a duplexer using four parameter display mode You must use a test adapter or a special 3 port test adapter to route the signals from the analyzer a two port instrument to the duplexer a three port device This example procedure is performed using one of the following test adapters m 8753D Option K36 Duplexer Test Adapter Qj 8753D Option K 39 3 Port Test Adapter Qj 8753ES Option H 39 3 Port Test Adapter use the same instructions as those for K 39 mode Definitions Thefollowing abbreviations are used in reference to a duplexer Tx Transmitter port Ant Antenna port Rx Receiver port Procedure 1 Press Preset 2 Connect the test adapter to the analyzer according to the instructions for your particular model Connect any test fixture or cables to the duplexer test adapter Refer to Figure 1 40 NOTE Yo
157. FSET OFFSET DELAY MAXIMUM FREQUENCY Enter a frequency greater than the maximum frequency range of the analyzer For example press Gin Then press STD OFFSET DONE 6 For the purposes of this example change the name of the standard by pressing LABEL STD and modifying the name to LINE 6 52 Calibrating for Increased Measurement Accuracy Calibrating for Non Coaxial Devices 7 When thetitle area shows the new label press DONE STD DONE DEFINED Assign the Standards to the Various TRL Classes 8 Toassign the calibration standards to the various TRL calibration casses press CAL KIT MODIFY SPECIFY CLASS MORE MORE TRL REFLECT 9 Since you previously designated standard 1 for the REFLECT standard press 10 Since you previously designated standard 6 for the LINE MATCH standard press TRL LINE OR MATCH 6 11 Since you previously designated standard 4 for the THRU LINE standard press TRL THRU 12 To complete the specification of dass assignments press SPECIFY CLASS DONE Label the Classes NOTE To enter the following label titles an external keyboard may be used for convenience 13 Press LABEL CLASS MORE MORE 14 Change the label of the TRL REFLECT dass to TRLSHORT 15 Change the label of the TRL LINE OR MATCH dass to TRLLINE 16 Change the label of the TRL THRU dass to TRLTHRU 17 Press LABEL CLASS DONE Label the Calibration Kit 18 Press LABEL KIT and create a label up to 8 characters long For this
158. Files with 10 11 12 1a 1b and 1c File Extensions The following files are only produced if you have an active calibration FileXX 10 isa binary file which stores the stimulus state of the instrument as it relates to an active calibration specifically the Power Sweep Setup Start Stop Center and Span settings The same type of file is produced if Channel 2 is active but the file extension is 20 instead of the 10 file extension mentioned in the previous paragraph Files FileXX 11 through 12 1a 1b and 1c are binary files which contain the 12 error correction coefficients for Channel 1 If Channel 2 is active it will have the same array but file extensions arein the form 21 22 2a 2b and 2c If you save in ASCII format only 10 and 1c are produced with 1c containing the entire error correction array in a two column real imaginary CITIfile format Files with File Extensions r1 through r8 FileXX r1 through r4 are produced when RAW ARRAY on OFF is turned ON They may be either binary or ASCII and contain the four raw uncorrected S parameters for channel 1 Channel 2 has the same array but file extensions are r5 through r8 In ASCII format the data is displayed as two columns of real imaginary numbers CITIfile format S11 appears first S21 appears second S12 appears third and S22 appears last 4 46 Printing Plotting and Saving Measurement Results Saving Measurement Results Files with d1
159. HREREESCRERISTEPGRERIdGOG S E 4 46 Saving Time Gated Frequency Data sii scsqesii bosiresebPRRRbP feReR RA 4644 p ek 4 48 Differences between Raw Data and Format Arrays 0 0c cece tee eee 4 49 ReSaving an Instrument State 14d a oe eH wd RE LIRA ER ORE ORES ECEREES e a PE 4 51 ere ee ee ee ee ee ee ee eer RR 4 51 To Delete an Instrument State File g1 4c0caeis44e 24 ees ee base Cw PEG r eb REY decade 4 51 TO Delete all Files cise chee scant Rb KR Pa a bereieriabaG R doe RGRRdoRgd Rack dado 4 51 Bea A EE used Xd ong He pd ae aco ae ETC eoi e POOR EGER CR i dca a ERS 4 52 ocr FIG uoa ad EE E PERTH ERE d EP PERF RT IDE ER V TRI E ER ERI d ERE 4 52 POs DISE xd darsasp eed dieters deb xd ae XC pt ORDERS d OP pd dee Quo PEI 4 53 Solving Problems with Saving or Recalling Files cece eee eee 4 53 If You Are Using an External Disk Drive 0 2 4 53 5 Optimizing Measurement Results Usna THiS Chapter 46i d ERE HACERTE iehe eet dd deeS eek ERAEER eee Eq dud 5 2 Taking Care of Microwave COPNEGEUFS exe dukquoxXx d p EQee TEREYHIPITPRUPARIPEQeN praes 5 3 Increasing Measurement Accuracy ssssseeselsee ene 5 4 liber ConPmeceIg CADES Vuqugiobed deque Xp dw PER OE I PORE ROC ER DOE IR XA cw Pob dod 5 4 Improper Calibration Technik des iue RRERRRASUEERTAIA IF P X YER EAT YS eteteadees 5 4 Sweeping Too Fast for Electrically Long Devices 0 0 20 c eee eee 5 4 Connector RepeatabllEy 2ss0c nian batowsstwdesiwisd
160. IBRATE MENU RESPONSE THRU 2 34 Making Mixer Measurements Phase or Group Delay Measurements 10 Replace the calibration mixer with the device under test If measuring group delay set the delay equal to the calibration mixer delay for example 0 6 ns by pressing Scale Ref ELECTRICAL DELAY 11 Scale the data for best vertical resolution Scale Ref AUTOSCALE Figure 2 25 Group Delay Measurement E xample CH1 B R delay 5 ns REF 0 S 1 19 524 ns eel 300 1000 000 GHz PRm Cor Del Smo N X f Hid Ofs Y N he uh uf f a v CENTER 300 000 000 GHz SPAN 100 000 000 GHz The displayed measurement trace shows the device under test delay relative to the calibration mixer This measurement is also useful when the device under test has pb6102d built in filtering which requires gt 30 dB range the maximum of R input PORT 1toPORT 2rangeis 2100 dB 2 35 Making Mixer Measurements Amplitude and Phase Tracking Amplitude and Phase Tracking The match between mixers is defined as the absolute difference in amplitude or phase response over a specified frequency range Thetracking between mixers is essentially how well the devices are matched over a specified interval This interval may be a frequency interval or a temperature interval or a combination of both You can make tracking measurements by ratioing the responses of two
161. Inelles liue rrr oiv Rd EXRAG RW lee IP RECPRGC QE Ed acp 7 29 Eledgrical De Sy taiicuch diese kee Geib owt RISES te Leia wee REICCRRG ie ER 7 33 Nose Reduction Techniques yea ccs up Pipe d doe Re Kad FERRE E ed CR SE ORE dea RR 7 34 Br GU oid od ae ee ee ee ee ee eee Te eee eer ERIT RES 7 34 DION 6 53452 L HEAT LESOSDOSEETESIS PETALS RE DER ADE qupd DOES 7 35 IF Banrgwidh PBedactloni jadsaceedioex perpe E E HSI Wd Tee eae ee 7 35 Measurement Ca Miri Sce tard adde ce srdd e946 CEPSE EDS PX X4 ab ER aR EDR we dy 7 37 What Is Accuracy Enhancement LeisasdweelERA T e kiiit dniki A OR EROR ies 7 37 What Causes Measurement EFTOFS iilius sa oda bo RO Yu CE PRG acRERE Ru PER 7 38 Characterizing Microwave Systematic Errors 0 00 eet eae 7 41 How Effective ls Accuracy Enhancement 0 0c 7 51 CalibrauoT ROUTINES a d etd cera dp REEEETNERCHENSPeUNTUHERPTEPSP CERES TERES 7 54 Response CANDO woaeeadeeacred ptuaepac rad eh epa tdrtreideq PEIppiIeqqbeq deside 7 54 Response and Isolation Calibration 0 0000 eee 7 54 Enhanced Respoansec alibratlor iis 6400544 ed G5 aisd REO DNS whe DEE wEDEY 7 54 Sl lang S22 OnePort CallbESE DE i2 Geese es hike beret eirebat iat bp eh ded RE RR 7 55 Fall Two Port GCallbrallpgfi gan copsesctactexxd vae Tes d Y SERS ORI ERROR be E 7 55 TRL SELREM Twe Port Callbrallon 2uin caieteraBieiebrpeBiG id k amp doe3d OA 7 55 E AL ik gin sab a LEK hai d e DPKG ERE e bae eC dw FER EORR da bed 7 55 Modfyngcs
162. LE Figure 2 20 shows the conversion loss of this low side LO mixer with output filtering Notice that the dynamic range from the pass band to the noise floor is well abovethe dynamic range limit of the R Channel If the mixer under test also contained amplification then this dynamic range would have been even greater due to the conversion gain of the mixer Figure 2 20 Example of Swept IF Conversion Loss Measurement CH1 B log MAG 10 dB REF 50 dB teal PRM PC Cor Ofs START 100 000 9000 MHz STOP 1 000 000 000 MHz 2 23 Making Mixer Measurements Fixed IF Mixer Measurements Fixed IF Mixer Measurements A fixed IF can be produced by using both a swept RF and LO that are offset by a certain frequency With proper filtering only this offset frequency will be present at thelF port of the mixer This measurement requires two external RF sources as stimuli Figure 2 22 shows the hardware configuration for the fixed IF conversion loss measurement This example measurement procedure uses the analyzer s test sequence function for automatically controlling the two external synthesizers with SCPI commands and making a conversion loss measurement in tuned receiver mode The test sequence function is an instrument automation feature internal to the analyzer For more information on the test sequence function refer to Using Test Sequencing to Test a Device on page 1
163. Making Reflection Response Measurements Figure 3 8 Device Response in the Frequency Domain CH1 Sj lin MAG 28 mU REF 69 mU START 380 OAA MHz STOP 3 200 008 AAA MHz aw000025 5 Totransform the data from the frequency domain to the time domain press TRANSFORM MENU BANDPASS TRANSFORM ON 6 To view the time domain over the length lt 4 meters of the cable under test press Format LIN MAG Start 0 GD The stop time corresponds to the length of the cable under test The energy travels about 1 foot per nanosecond or 0 3 meter ns in free space Most cables have a relative velocity of about 0 66 the speed in free space Calculate about 3 ns foot or 10 ns meter for the stop time when you are measuring the return trip distance to the cable end 7 To enter the relative velocity of the cable under test press MORE VELOCITY FACTOR and enter a velocity factor for your cable under test NOTE Most cables have a relative velocity of 0 66 for polyethylene dielectrics or 0 7 for teflon dielectrics If you would like the markers to read actual one way distance rather than return trip distance enter one half the actual velocity factor Then the markers will read the actual one way distance to the reflection of interest rather than the electrical length that assumes a relative velocity of 1 1 Velocity Factor E where e is the relative permittivity of t
164. Markers The analyzer allows you to set measurement parameters with the markers without going through the usual key sequence You can change certain stimulus and response parameters to make them equal to the current active marker value Setting the Start Frequency l Press and turn the front panel knob or enter a value from the front panel keypad to position the marker at the value that you want for the start frequency 2 Press MARKER gt START tochangethe start frequency value to the value of the active marker Figure 1 22 Example of Setting the Start Frequency Using a Marker CH1 S2 log MAG 1 dB REF 50 dB 1 72 403 dB ul CHL Sg log MAG 18 dB REF 59 dB 1 74 689 dB i28 jii sgo MHz L CENTER 134 000 008 MHz SPAN 35 008 008 MHz as pat e i CENTER 135 388 750 MHz SPAN 31 062 508 MHz pg6232 1 34 Making Measurements Using Markers Setting the Stop Frequency 1 Press and turn the front panel knob or enter a value from the front panel keypad to position the marker at the value that you want for the stop frequency 2 Press MARKER STOP to change the stop frequency value to the value of the active marker Figure 1 23 Example of Setting the Stop Frequency Using a Marker CHi Sag log MAG 18 dB REF 50 dB 1 72 085 dB CH S2 log MAG i8 dB REF 50 dB 1 71 78 dB fw T 145 46 592 MHz be 14
165. O Specifies dots only at the points that are plotted 1 g 2 3 yo 5S z 6 qs pg6135d NOTE You must define the line types for each measurement channel channel 1 3 and channel 2 4 Choosing Scale Press SCALE PLOT until the selection appears that you want m Choose SCALE PLOT FULL if you want the normal scale selection for plotting This indudes space for all display annotations such as marker values and stimulus values The entire analyzer display fits within the defined boundaries of P1and P2 on the plotter while maintaining the exact same aspect ratio as the display m Choose SCALE PLOT GRAT if you want the outer limits of the graticule to correspond to the defined P1 and P2 scaling point on the plotter Intended for plotting on preprinted rectangular or polar forms 4 15 Printing Plotting and Saving Measurement Results Defining a Plot Function Figure 4 7 Locations of Pland P2in SCALE PLOT GRAT Mode P1 Choosing Plot Speed P2 Press PLOT SPEED until the plot speed appears that you want m Choose PLOT SPEED FAST for normal plotting Speed provides a more consistent line width m Choose PLOT SPEED SLOW for plotting directly on transparencies The slower To Reset the Plotting Parameters to Default Values Press Copy DEFINE PLOT MORE MORE YES Table 4 5 Plotting Parameter D
166. OFFSET LOSS allows you to specify energy loss due to skin effect along a one way length of coax offset The value of loss is entered as ohms nanosecond or Giga ohms second at 1 GHz Such losses are negligible in waveguide so enter 0 as the loss offset OFFSET ZO allows you to specify the characteristic impedance of the coax offset Note This is not the impedance of the standard itself For waveguide the offset impedance as well as the system ZO must always be set to 10 MINIMUM FREQUENCY allows you to define the lowest frequency at which the standard can be used during measurement calibration n waveguide this must be the lower cutoff frequency of the standard sothat the analyzer can calculate dispersive effects correctly see OFFSET DELAY MAXIMUM FREQUENCY allows you to define the highest frequency at which the standard can be used during measurement calibration n waveguide this is normally the upper cutoff frequency of the standard COAX defines the standard and the offset as coaxial This causes the analyzer to assume linear phase response in any offsets WAVEGUIDE defines the standard and the offset as rectangular waveguide This causes the analyzer to assume a dispersive delay see OFFSET DELAY Label Standard Menu This menu allows you to label reference individual standards during the menu driven measurement calibration sequence The labels are user definable using a character set shown on the disp
167. POSITION RETURN CENTER 134 000 606 MHz SPAN 43000 686 MHz 4 Press Chan 4 or press Chan 2 set AUX CHAN toON This enables channel 4 and the screen now displays four separate grids as shown in Figure 1 10 Channel 4 is in the lower right quadrant of the screen Making Measurements Using Display Functions Figure 1 10 Four Channel Display 2 Sep 1338 14 15 57 CHi LOG 5 dB REF 2 dB CH2 LOG 18 de REF 58 dB LA Set DUAL CHAN H EO Ee peg espe epe AUX CHAM ON off PR tip PRm OTATTE 4 PARAM cea A e T CA DISPLAYS Baebes CECE ee 41 t t CENTR 134 888 MHz SPAN 45 888 MHz CENTR 134 888 MHz SPAN 45888 MHz CH3 LOG 18 dB REF 58 dB CH4 LOG 5 dB REF 3 dB 812 22 Coo zs LI LL LLLLLLI I NLLLLLLLLI LL 7 d EISE ES CIS CHANNEL Lj POSITION E ABEE efi Mea tlie 3 3 Pt tty yy tt fet ees Yl fe ee s ET gp T RETURN CENTRE 134 668 MHz SPAN 45 888 MHz CENTR 134 888 MHz SPAN 43868 MHz BRA 5 Press Chan 4 Observe that the amber LED adjacent tothe key is lit and the CH4 indicator on the display has a box around it This indicates that channel 4 is now active and can be configured 6 Press Marker MARKER 1 MARKER 2 Markers 1 and 2 appear on all four channel traces Rotating the front panel control knob moves marker 2 on all four channel traces Notethat the active function in this case the marker frequency is the same color and in the same grid as the active cha
168. PPLICABLE LAW AGILENT DISCLAIMS ALL WARRANTIES EITHER EXPRESS OR IMPLIED WITH REGARD TO THIS MANUAL AND ANY INFORMATION CONTAINED HEREIN INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AGILENT SHALL NOT BE LIABLE FOR ERRORS OR FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES IN CONNECTION WITH THE FURNISHING USE OR PERFORMANCE OF THIS DOCUMENT OR ANY INFORMATION CONTAINED HEREIN SHOULD AGILENT AND THE USER HAVE A SEPARATE WRITTEN AGREEMENT WITH WARRANTY TERMS COVERING THE MATERIAL IN THIS DOCUMENT THAT CONFLICT WITH THESE TERMS THE WARRANTY TERMS IN THE SEPARATE AGREEMENT WILL CONTROL Assistance Product maintenance agreements and other customer assistance agreements are available for Agilent Technologies products For any assistance contact your nearest Agilent Technologies sales or service office See Table 8 1 for the nearest office Safety Notes The following safety notes are used throughout this manual Familiarize yourself with each of the notes and its meaning before operating this instrument All pertinent safety notes for using this product are located in Chapter 8 Safety and Regulatory Information WARNING Warning denotes a hazard It calls attention to a procedure which if not correctly performed or adhered to could result in injury or loss of life Do not proceed beyond a warning note until the indicated conditions are fully understood and met CAUTION Cautio
169. Printer You can output plot files to an HPGL compatible printer using the DOS command line and the files created in the previous steps This example assumes that the escape sequence files and the plot files are in the current directory and the selected printer port is PRN Command Remarks Co type hpglinit gt PRN C type PLOTOO FP PRN C type exithpgl gt PRN 4 24 Printing Plotting and Saving Measurement Results Outputting Multiple Plots to a Single Page Using a Printer Outputting Multiple Plots to a Single Page Using a Printer Refer to Plotting Multiple Measurements Per Page Using a Pen Plotter on page 4 18 for the naming conventions for plot files that you want printed on the same page You can use the following batch file to automate the plot file printing In this example the batch fileis be saved as do_plot bat However before running this batch file you must first create the hpglinit file and the exithpgl1 file described in Outputting Plot Files from a PC toan HPGL Compatible Printer on page 4 23 rem rem rem rem rem rem rem rem rem rem rem Name do plot Descripti on output HPGL initialization sequence to a file spooler append all the requested plot files to the spooler append the formfeed sequence to the spooler copy the file to the printer This routine uses COPY instead of PRINT because COPY rem will not return until the action is completed PRINT rem will queuethe file so the subsequent
170. R PHASE AUTO SCALE 1 43 Making Measurements Measuring Electrical Length and Phase Distortion You may also want to select settings for the number of data points averaging and IF bandwidth 3 Substitute a thru for the device and perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU 4 Reconnect your test device 5 To better view the measurement trace press Scale Ref AUTO SCALE Noticethat in Figure 1 34 the SAW filter under test has considerable phase shift within only a 2 MHz span Other filters may require a wider frequency span to see the effects of phase shift Thelinearly changing phase is due tothe device s electrical length You can measure this changing phase by adding electrical length electrical delay to compensate for it Figure 1 34 Linearly Changing Phase CH1 S2 phase 100 REF O I PRm Cor 100 4 di CENTER 134 000 000 MHz SPAN 2 000 000 MHz pa5103e 6 To place a marker at the center of the band press and turn the front panel knob or enter a value from the front panel keypad 7 To activate the electrical delay function press Marker Fctn MARKER DELAY This function calculates and adds in the appropriate electrical delay by taking a 10 span about the marker measuring the Ad and computing the delay as the negative of A A frequency Alternatively press ELECTRICAL DELAY and turn the
171. RR 3 15 Setting the Frequency Range for Time Domain Low Pass 000 eee eaee 3 15 Reflection Measurements in Time Domain Low Pass 000 0c cetera 3 16 Fault Location Measurements Using Low Pass liliis sees 3 18 Transmission Measurements in Time Domain Low Pass 200 0 eee sess 3 19 Transforming CW Time Measurements into the Frequency Domain 3 22 Forward Transform Measurements amp isssdeskERREERRRERKRREKERRENRRGREZYERR ERG 3 22 AEK d bac Pee Nac dox POE en bac e ed aa dd epee edad acd Raid eda Rd a POOR qe eda do Pe dy 3 26 XUL ODE 66426054 RERO ERE ESTROUS THAI SEA CERE E HACER IEEE 3 27 Sc fee XO Hee TE PRI RA E EYE Xe EPOR CIE ded PERCY EORR QUOE qoe E E a p dede 3 30 FoesolIL OI qucddebesesi T RF ERO kiA HEQREER E RAN Earn 3 32 Response Res OU OIL aua aped eve SRE KN oe SRE REAL E e P REE IEG MOR RR NEES wee 3 32 Rade RCSL ON riete ERE EP RENT AREE SE TOL ERA EA CER IER 3 34 Se ee ee eee ee eee re Rie que dc ied aed Pa Cdp ee UP dox dba dede Poen 3 35 SeLUig CB QBUS casado qeu Es ob RERHCC EURO EC ERR ORG R ERE es ERREUR ER LR dees 3 35 Selecting Gabe SDap a a SOROS acie eq deb ERE ES Eh eb ER d debe Era 3 36 vii Contents 4 Printing Plotting and Saving Measurement Results viii eng THIS GUS cins badd Werie ne XX AR X quad d Eq PEE d wed doedaqu qe xe 4 2 Printing or Plotting Your Measurement Results 000 cece ee sess 4 3 Cour s PEDE EAREDDI eaa d de xd de Reward
172. RRRROG EWE AG E ewes Rae Rae ERA 8 2 mue c mb s oaa 4 daret Te Pace Pd a Mee a et p dress dae aon ad x dard do 3 dana bd des 8 4 instrument MIKIIdS costos RAE ERECTA IRE FEX LENS DER AA E HERE ER E RR RR 8 4 Solely LORI UEUIIS a oss aS OWS em ORE RP eH TEER ONE GR EEXCG Gd qqedbqce pee des 8 5 Sane Earth OGPOUDO cispn eub ersrPetiebereskibePeberpRegdudGodxdo 4 gREr d EG rd pd ee 8 5 Bere AOE VINE PONE iaa addet Pack die PCI del dae DORE ORES SON Ic Xa Pow Pod arcae da 8 5 Ser cti s s eba 24864 P RE RIPId E EREC IDEE PERITI RELAX ERE TE ETLICHE E D E RE 8 6 CONE Al uaria de e ORS ARTS Qd He QAO eR EX QE PRAE RT OSES ONS DES 8 7 Compliance with German FTZ Emissions Requirements uussa 8 8 Compliance with German Noise Requirements lle eres 8 8 Compliance with Canadian EMC Requirements usleseleee eere 8 8 Detar alia C ODTOHITIL aaa x vao pp copa EREE Ww qeEUE PERPE P Ead E CPP Edd 8 9 xiii Contents xiv l Making Measurements Making Measurements Using This Chapter Using This Chapter Th is chapter contains the following example procedures for making measurements Mixer and time domain measurements are covered in Chapter 2 Making Mixer Measurements and Chapter 3 Making Time Domain M easurements This chapter also describes how to use most display marker and sequencing functions Making a Basic M easurement on page 1 4 Measuring M agnitude and Insertion Phase Response on page 1 7
173. TRG ON POINT Incrementing the Source Frequencies MORE TITLE ERASE TITLE Input as title FREQ CW UP DONE SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL Decrementing the Loop Counter DECISION MAKING DECR LOOP COUNTER IF LOOP COUNTER O SEQUENCE 2SEQ2 2 29 Making Mixer Measurements Fixed IF Mixer Measurements Labeling the Screen MORE TITLE ERASE TITLE Input as title MEASUREMENT COMPLETED DONE DONE SEQ MODIFY Press NEW SEQ MODIFY SEQ SEQUENCE 2SEQ2 and the analyzer will display the following sequence commands SEQUENCE SEQ2 Start of Sequence WAIT x 1 xi MANUAL TRG ON POINT TITLE FREQ CW UP PERIPHERAL HPIB ADDR 19x1 TITLE TO PERIPHERAL ERIPHERAL HPIB ADDR I TO PERIPHERAL ECR LOOP COUNTER IF LOOP COUNTER lt gt 0 THEN DO SEQUENCE 2 TITLE MEASUREMENT COMPLETED H p E P 2 T D 2 Press the following keys to run the sequences DONE SEQ MODIFY DOSEQUENCE SEQUENCE 2SEQ2 When the prompt CONNECT MIXER appears connect the equipment as shown in Figure 2 22 2 30 Making Mixer Measurements Fixed IF Mixer Measurements Figure 2 22 Connections for a Conversion Loss Using Tuned Receiver Mode NETWORK ANALYZER 19 21 Ext Reference External ous External RF Source LO Source pa548e When the
174. The analyzer can automatically calculate and display the bandwidth BW center frequency CENT Q and loss of the device under test at the center frequency Q stands for quality factor defined as the ratio of a circuit s resonant frequency to its bandwidth These values are shown in the marker data readout 1 Press Marker Search and SEARCH MAX to place the marker near the center of the filter passband Press MKR ZERO if you want the bandwidth relative to the maximum 3 Press Marker Search to access the marker search menu Press WIDTHS ON tocalculate the center stimulus value bandwidth and the Q of a bandpass or band reject shape on the measurement trace If you want to changethe amplitude value default is 3 dB that defines the passband or reject band press WIDTH VALUE and enter the new value from the front panel keypad Figure 1 31 Example of Searching for a Bandwidth Using Markers CH1 Soy lag MAG 10 dB REF 45 dB 1 638 dB d MARKER WIDTH URLUE 3 HB 41 CENTER 134 800 80008 MHz SPRN 38 800 8080 MHz aw000055 Tracking the Amplitude that You Are Searching 1 Set up an amplitude search by following one of the previous procedures in To Search for a Specific Amplitude on page 1 39 Press Marker Search TRACKING ON totrack the specified amplitude search with every new trace and put the active marker on that point When tracking i
175. User s Guide Agilent Technologies 8753E S Option O11 Network Analyzer S Agilent Technologies Part Number 08753 90479 Printed in USA J une 2002 Supersedes February 2001 Copyright 1999 2002 Agilent Technologies Inc Notice The information contained in this document is subject to change without noti ce Agilent Technologies makes no warranty of any kind with regard to this material including but not limited to the implied warranties of merchantability and fitness for a particular purpose Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing performance or use of this material Certification Agilent Technologies certifies that this product met its published specifications at the time of shipment from the factory Agilent Technologies further certifies that its calibration measurements are traceable to the U nited States National Institute of Standards and Technology to the extent allowed by the I nstitute s calibration facility and to the calibration facilities of other International Standards Organization members Regulatory Information The regulatory information is located in Chapter 8 Safety and Regulatory Information Warranty THE MATERIAL CONTAINED IN THIS DOCUMENT IS PROVIDED AS IS AND IS SUBJ ECT TO BEING CHANGED WITHOUT NOTICE IN FUTURE EDITIONS FURTHER TO THE MAXIMUM EXTENT PERMITTED BY A
176. a user defined TRM calibration kit 6 56 labeling the calibration kit 6 57 labeling the classes 6 57 modifying the standard definitions 6 56 performing the TRM calibration 6 58 TTL 1 O menu 1 107 input decision making 1 107 out menu 1 111 output for controlling peripherals 1 107 tuned receiver mode 2 24 2 26 7 85 Index 12 in depth description 7 86 test setup typical 7 86 two sources addressing and configuring 2 27 two port calibration full 7 55 two port calibration TRL LRM 7 55 two port error model 7 46 type N connector sex darifying 6 4 types of error correction 6 10 finite impulse width or rise time 3 27 sidelobes 3 27 U uncoupling display markers 1 31 understanding harmonic operation 1 57 spur avoidance 5 17 understanding S parameters 7 20 upper stopband parameters 1 68 using continuous correction mode 6 38 using external calibration 5 12 using fast 2 port calibration 5 12 using sample and sweep correction mode 6 36 using swept list mode 5 9 detecting IF delay 5 10 using the parallel port 7 79 copy mode 7 79 GPIO mode 7 80 V vector error correction 7 8 verification performance 5 5 verifying performance 7 64 vertical axis 3 13 3 14 3 17 3 20 3 22 viewing a single measurement channel 5 12 viewing plot files on a PC 4 20 using AmiPro 4 21 using Freelance 4 21 Ww what you can save to a computer 4 35 what you can savetoa floppy disk 4 35
177. accomplished with remote onl y commands Refer to the programmer s guide for information on how to use external calibration To Use Fast 2 Port Calibration With a 2 port calibration on faster trace updates are possible by not measuring the reverse path for every forward sweep This is controlled by the test set switch command This is convenient for tuning applications because it gives a faster trace update When making measurements using full two port error correction the following types of test set switching can be defined by the user Hold In this modethe analyzer does not switch between the test ports on every sweep The measurement stays on the active port after an initial cyding between the ports Thefastest measurements can be made by using this type of test set switching Pressing the key changing to a different S parameter measurement or any other action which restarts a sweep will cause the test set to switch and cycle between the ports 5 12 Optimizing Measurement R esults Increasing Sweep Speed Continuous n this mode the analyzer will switch between the test ports on every sweep Although this type of test set switching provides the greatest measurement accuracy it requires a reverse sweep for every forward sweep Number of Sweeps n this mode there is an initial cycling between the test ports and then the measurement stays on the active port for a user defined number of sweeps After the specified number of sweeps h
178. acteristics of the test device and it usually produces the major ambiguity in measurements of low reflection devices Source Match Source match is defined as the vector sum of signals appearing at the analyzer receiver input due to the impedance mismatch at the test device looking back into the source as well as to adapter and cable mismatches and losses In a reflection measurement the source match error signal is caused by some of the reflected signal from the test device being reflected from the source back toward the test device and re reflected from the test device This is illustrated in Figure 7 22 In a transmission measurement the source match error signal is caused by reflection from the test device that is re reflected from the source Source match is most often given in terms of return loss in dB thus thelarger the number the smaller the error Figure 7 22 Source Match Coupled Output AT anal L bs Main AJ tt Coupler DUT 5s Output Reflected A Mecum from the Reflected source Re reflected Incident pg647d Theerror contributed by source match is dependent on the relationship between the actual input impedance of the test device and the equivalent match of the source It is a factor in both transmission and reflection measurements Source match is a particular problem in measurements wherethere is a large impedance mismatch at the measurement plane For example ref
179. ad match still interact with the input and output matches of the DUT which contributes to transmission measurement errors These errors are largest for devices with highly reflective ports Isolation Crosstalk Leakage of energy between analyzer signal paths contributes to error in a transmission measurement much like directivity does in a reflection measurement Isolation is the vector sum of signals appearing at the analyzer samplers due to crosstalk between the reference and test signal paths This indudes signal leakage within the test set and in both the RF and IF sections of the receiver The error contributed by isolation depends on the characteristics of the test device Isolation is a factor in high loss transmission measurements H owever analyzer system isolation is more than sufficient for most measurements and correction for it may be unnecessary For measuring devices with high dynamic range accuracy enhancement can provide improvements in isolation that are limited only by the noise floor Generally the isolation falls below the noise floor therefore when performing an isolation calibration you should use a noise reduction function such as averaging or reduce the IF bandwidth Frequency Response Tracking Thisis the vector sum of all test setup variations in which magnitude and phase change as a function of frequency This includes variations contributed by signal separation devices test cables adapters and variat
180. al TDR response which displays the reflected signal in a real format volts versus time or distance on the horizontal axis Thereal format can also be used in thelow pass impulse mode but for the best dynamic range for simultaneously viewing large and small discontinuities use the log magnitude format 3 17 Making Time Domain Measurements Time Domain Low Pass Mode Fault Location Measurements Using Low Pass As described the low pass mode can simulate the TDR response of the test device This response contains information useful in determining the type of discontinuity present Figure 3 13 illustrates the low pass responses of known discontinuities Each circuit element was simulated to show the corresponding low pass time domain S41 response waveform The low pass mode gives the test device response either to a step or to an impulse stimulus M athematically the low pass impulse sti mulus is the derivative of the step stimulus Figure 3 13 Simulated Low Pass Step and Impulse Response Waveforms R eal Format ELEMENT STEP RESPONSE IMPULSE RESPONSE OPEN EM EN UNITY REFLECTION UNITY REFLECTION SHORT EM i UNITY REFLECTION 180 UNITY REFLECTION 180 RESISTOR MN R Zg POSITIVE LEVEL SHIFT POSITIVE PEAK RESISTOR o o Noo R Zg NEGATIVE LEVEL SHIFT NEGATIVE PEAK INDUCTOR 7 POSITIVE PEAK POSITIVE THEN NEGATIVE PEAKS CAPACITOR J NEGATIVE PEAK NEGATIVE
181. al delay 7 33 electrical delay block 7 8 electrical delay determining 6 75 electrical delay setting 1 37 electrically long devices 5 4 electronic calibration See E Cal eliminating unwanted mixing and leakage signals 2 6 embedding loop counter value in title 1 105 enhanced frequency response error correction 6 22 enhanced reflection error correction 6 22 6 25 enhancement accuracy 7 37 entering the power sensor calibration data 6 34 deleting frequency signals 6 35 editing frequency segments 6 34 error minimizing error while using adapters 6 49 error correcting measurements 6 10 error correction enhanced frequency response 6 22 enhanced reflection 6 22 6 25 frequency response 6 12 full two port 6 29 one port reflection 6 26 error correction 1 5 stimulus state 6 9 error correction vector 7 8 errors measurement 7 38 exit HPGL mode 4 24 sending to the printer 4 24 external calibration 5 12 disk drive 4 53 external source mode 7 83 capture range 7 85 compatible sweep types 7 85 CW frequency range 7 85 external source auto 7 84 external source manual 7 84 in depth description 7 84 locking onto a signal with frequency modulation component 7 85 primary applications 7 83 requirements 7 85 typical test setup 7 83 F fabricating and defining calibration standards for TRL LRM 7 72 fast 2 port calibration 5 12 fault location measurements using low pass 3 18 features that opera
182. albr auo IUS auuisesqEPTSPeTARC ee ee HERE QE RA ERE EYERPI RES 7 56 EHUPHTIQIIS 4 40 v3 ied 3 E Ca PRORA ORE E ebd pP TET FR RI ERE P P Xd WO dar RIQ Rew eRe Ps 7 56 got eee eee Tee OE ee Tee eee ree ee ee ee ee ee ROPA 7 57 Mody Calibration KEMEM uva debe piede bed Ce Yd dA eer kd web ERG Ee LORE 7 57 Yey Per TOF al IO erriei khe Ak PSOE d erbdsljisbaiY iat db Eqs 7 64 Saving Modified Calibration Kits toa DISK iiis se re x RR ER RR 7 65 Modifying and Saving a Calibration Kit from the Calibration Kit Selection Menu 7 65 TRE CRN CONO SUD 4 ike wits wa dede X Ead e CP INS deu P e E dean ERR UE ie E 7 66 Why Use TRE S allbratloni diese 44i DERRPSIDR Geeta ee bebe T4Q C ERO P REER lee RR 7 66 FRE TWO cucqqueqdebkadqxte querd4Xxeqe xvEp o eTesQrpekEG de ixkqrkd e ed 7 67 How TRL ERM Calibration WOKS sacssesbskazekbrbkg RE da ER GR Eon ERGORCA Rd OR FOR 7 67 Improving Raw Source Match and Load Match for TRL LRM Calibration 7 70 The TRL Calibration Procedule iiiseca d RH HC HERR iiiki nnak REESE Slee rs as 7 71 GPIB ODE ee eee re er eefqi qe eX ATTERRA ee ee ee cee 7 77 Loca REN codesusudisdedieieidTPiQbehesda dd iube d RAEADR ASE ieee 7 77 GPIB STATUS MICI S espe wd Rea ee om DRE RH eoe SORENESS ode ce Yee bd RE 7 78 System Controller MOOR suis ERE P ERRE QE HII E ERI RE SEA RAP EEPTITqQ P wees 7 78 Contents TalkerListener M ODE Ls ai d D 4b eb ORARE HEAHERE OPERI iia shade es IAS XEPRIdER P ET ed 7 78 Pass COMO MS LequeterhteQ
183. alibration results Refer to Perform the Confidence Check on page 6 67 10 Savethe calibration results by pressing Save Recall Display the Module Information Display information about the module by pressing ECal MENU CONFIGURE MODULE INFO A text window is displayed that contains the following information about the selected module 1 PC interface unit port to which it is connected 6 Number of measurement points 2 M odel number 7 Start minimum frequency 3 Serial number 8 Stop maximum frequency 4 Connector type 9 Suggested warmup time 5 Date of last certification 10 Warmup status This is the remaining time on an internal analyzer timer The timer simply counts down the recommended E Cal module warm up time When the timer reaches zero a message is displayed indicating that the ECal moduleis ready The E Cal module temperature or status is not read Thetimer is reset when the analyzer is powered up or preset or when a new module is attached 6 66 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal Perform the Confidence Check The confidence check is a means of visually checking the quality of the calibration The confidence check displays the currently measured data DATA trace and the factory premeasured data MEM trace for the module s confidence state The confidence state an independent reference standard was not used for the
184. all Time 5 18 6 Calibrating for Increased Measurement Accuracy 6 1 Calibrating for Increased Measurement Accuracy How to Use This Chapter How to Use This Chapter Th 6 2 is chapter is divided into the following subjects Calibration Considerations on page 6 4 Procedures for Error Correcting Your Measurements on page 6 10 frequency response error correction frequency response and isolation error correction enhanced frequency response error correction with enhanced reflection error correction one port reflection error correction full two port error correction Power M eter Measurement Calibration on page 6 33 Calibrating for Noninsertable Devices on page 6 40 adapter removal calibration matched adapters modify the cal kit thru definition Calibrating for Non Coaxial Devices on page 6 52 TRL calibration LRM calibration Calibrating Using Electronic Calibration ECal on page 6 60 Adapter Removal Using ECal on page 6 71 Calibrating for Increased Measurement Accuracy Introduction Introduction The accuracy of network analysis is greatly influenced by factors external to the network analyzer Components of the measurement setup such as interconnecting cables and adapters introduce variations in magnitude and phase that can mask the actual response of the device under test Error correction is an accuracy enhancement procedure that removes sy
185. ally channel dependent channel 1 cannot access the channel 2 memory trace or vice versa M emory traces can be saved with instrument states one memory trace can be saved per channel for each saved instrument state There are up to 31 save recall registers available so the total number of memory traces that can be present is 128 including the four active for the current instrument state The memory data is stored as full precision complex data Memory traces must be displayed in order to be saved with instrument states Additional data can be stored onto 3 5 inch floppy disks using the front panel disk drive NOTE You may not be able to store 31 instrument states if they include a large amount of calibration data The calibration data contributes considerably to the size of the instrument state file and therefore the available memory may be full prior to filling all 31 registers Two trace math operations are implemented e DATA MEM data memory e DATA MEM data memory Notethat normalization is DATA MEM not DATA MEM Memory traces are saved and recalled and trace math is done immediately after error correction This means that any data processing done after error correction including parameter conversion time domain transformation Option 010 scaling etc can be performed on the memory trace You can also use trace math as a simple means of error correction although that is not its main purpose All data processing operations tha
186. although a procedure similar to the System verification procedure may be used 7 64 Operating Concepts Modifying Calibration Kits Saving Modified Calibration Kits to a Disk The calibration kit along with any calibration data and other instrument state information can be saved to an ISTATE file on a floppy disk To save a modified calibration kit with an instrument state press CAL KIT SELECTCAL KIT USER KIT Save Recall SAVE STATE Modifying and Saving a Calibration Kit from the Calibration Kit Selection Menu To modify a calibration kit from the calibration kit selection menu press CALKIT SELECTCALKIT MODIFY KIT DONE MODIFIED To savethe modified calibration kit press CAL KIT SELECT CAL KIT USERKIT SAVEUSERKIT or Save Recall SAVE STATE Ensurethat USER KIT is underlined before saving the modified user kit 7 65 Operating Concepts TRL LRM Calibration TRL LRM Calibration The network analyzer has the capability of making calibrations using the TRL thru reflect line method This section contains information on the following subjects Why UseTRL Calibration TRL Terminology How TRL LRM Calibration Works e Improving Raw Source Match and Load Match for TRL LRM Calibration TheTRL Calibration Procedure Requirements for TRL Standards TRL Options Why Use TRL Calibration This method is convenient in that calibration standards can be fabricated for a specific measurement enviro
187. ample of Setting the Reference Value Using a Marker CH1 Sg log MAG 10 0B REF P 9E Ice AN CHi Sg log MAG 10 dB REF 23 55 dB 1 23 55 dB 135 459 sda MHz TS5 469 5AP Mur i m AN yy CENTER 134 8800 0AB MHz SPON 3520081008 Hz CENTER 134 0800 820 MHz SPAN 35 0880 MHz pg6228 Setting the Electrical Delay This feature adds phase delay to a variation in phase versus frequency therefore it is only applicable for ratioed inputs 1 37 Making Measurements Using Markers 1 Press Format PHASE 2 Press and turn the front panel knob or enter a value from the front panel keypad to position the marker at a point of interest 3 Press MARKER DELAY to automatically add or subtract enough line length tothe receiver input to compensate for the phase slope at the active marker position This effectively flattens the phase trace around the active marker You can use this to measure the electrical length or deviation from linear phase Additional electrical delay adjustments are required on devices without constant group delay over the measured frequency span Figure 1 27 Example of Setting the Electrical Delay Using a Marker CRECSAELIOBRORg c c ee REO CH1 S2 phase S REF B 1 198 89 m 141 20 al MHz Im AA d pm EET REPARARE i
188. ance The intersecting dotted lines on the Smith chart represent constant resistance and constant reactance values normalized to the characteristic impedance Zo of the system Reactance values in the upper half of the Smith chart circle are positive inductive reactance and those in the lower half of the circle are negative capacitive reactance The default marker readout is in ohms Q to measure resistance and reactance R X Additional marker types are available in the Smith marker menu The Smith chart is most easily understood with a full scale value of 1 0 If the scale per division is less than 0 2 the format switches automatically to polar If the characteristic impedance of the system is not 50 ohms modify the impedance value recognized by the analyzer by pressing MORE SET ZO the impedance value x1 An inverted Smith chart format for admittance measurements is also available This is shown in Figure 7 9 Access this by selecting SMITH CHART in the format menu and pressing MKR MODE MENU SMITH MKR MENU G 4BMKR The Smith chart is inverted and marker values are read out in siemens S to measure conductance and susceptance G B Figure 7 9 Standard and Inverse Smith Chart Formats 1 11 1U FS i 9 2383 ohm 11 839 ohm 10 292 nh MARKERS 126 650 000 MHz DISCRETE CH1 S11 1uFS 1 70 679 aS 30 037 mS 62 68 pf 128 850 000 MHz LIN MKR CONTINUOUS Cor LOG MKR 7 MARKER 1 SU 126 65 MHz T DA Re Im MKR
189. and d2 File Extensions There are two type of files with d1 and d2 file extensions There is FileXX d1 or d2 and DataXX d1 or d2 FileXX d1 produced only when DATA ARRAY on OFF isturned ON may be either binary or ASCII This file contains the error corrected measurement data but without port extensions or electrical delay In ASCII format this is a two column real imaginary array CITIfile format without any direct frequency information S11 appears first S21 second 12 third and S22 last If Channel 2 is active the same type of file is produced but the file extension is d2 If dual display is on both d1 and d2 files are produced DataXX d1 created only when DATA ONLY on OFF is turned ON is either a binary file or an ASCII filein CITIfile format Turningthe DATA ONLY on OFF softkey ON suppresses the generation of all the previous file types The contents of this file are identical to those of the FileXX d1 file The same type of file is produced if Channel 2 is active but thefile extension is d2 If dual display is on both d1 and d2 files are produced NOTE The DataXX files are much smaller than an entire instrument state and are the best way to get just the data you want without saving the entire instrument state Selecting more than one disk save option does not confuse the analyzer and simply produces all files associated with the selected options The only exception tothis is that selecting DATA ONLY on OFF suppress
190. and SYSTEM CONTROLLER if there is no external controller connected to the GPIB bus c Press and USE PASS CONTROL ifthere is an external controller connected to the GPIB bus Choose PARALLEL if your printer has a parallel Centronics interface and then configure the print function as follows Press and then select the parallel port interface function by pressing PARALLEL until the correct function appears m If you choose PARALLEL COPY the parallel port is dedicated for normal copy device use printers or plotters m If you choose PARALLEL GPIO the parallel port is dedicated for general purpose I O and cannot be used for printing or plotting Choose SERIAL if your printer has a serial RS 232 interface and then configure the print function as follows a Press PRINTER BAUD RATE and enter the printer s baud rate followed by x1 b To select the transmission control method that is compatible with your printer press XMIT CNTRL transmit control handshaking protocol until the correct method appears LY If you choose Xon Xoff the handshake method allows the printer to control the data exchange by transmitting control characters to the network analyzer LY If you choose DTR DSR the handshake method allows the printer to control the data exchange by setting the electrical voltage on one line of the RS 232 serial cable Becausethe DTR DSR handshake takes placein the hardware rather than the firmware or s
191. and a measurement calibration performed on the full frequency list one or all of the frequency segments can be measured and displayed without loss of calibration When the LIST FREQ STEPPED key is pressed the network analyzer sorts all the defined frequency segments into CW points in order of increasing frequency It then measures each point and displays a singletrace that is a composite of all data taken If duplicate frequencies exist the analyzer makes multiple measurements on identical points to maintain the specified number of points for each subsweep Since the frequency points may not be distributed evenly across the display the display resolution may be uneven and more compressed in some parts of thetrace than in others However the stimulus and response readings of the markers are always accurate Because the list frequency sweep is a stepped CW sweep the sweep ti me is slower than for a continuous sweep with the same number of points Segment Menu The LIST FREQ STEPPED softkey provides access to the segment menu which allows you to select any single segment SINGLE SEG SWEEP in the frequency list or all of the segments ALL SEGS SWEEP in the frequency list Seethe following information on how to enter or modify the list frequencies If nolist has been entered the message CAUTION LIST TABLE EMPTY is displayed A tabular printout of the frequency list data can be obtained usingthe LIST VALUES function in the copy menu
192. andwidth Test Activated 15 Jun 2888 12 35 53 Hi 21 LOG 18 dB REF 30 dB Bit Wide Channel 1 ay Bandwidth Test Result CENTER 321 888 08080 GHz SPAN 2080 00A 986 GHz pa5192e Displaying the Bandwidth Markers 1 Display the bandwidth markers by pressing the BW MARKER on OFF softkey until ON is displayed on the softkey When the bandwidth markers are displayed a marker is placed on each side of the peak amplitude at a position equal tothe N dB Points value below the peak The markers are placed at the 40 dB points on the signal in Figure 1 73 The bandwidth markers resemble the following symbol T 1 94 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter Figure 1 73 Bandwidth Markers Placed 40 dB Below the Bandpass Peak 15 Jun 2888 12 39 23 EHI 21 LOG 16 dB REF 30 dB BWI Wide PRm NdB Bandwidth Markers CENTER 321 000000 GHz SPAN 200 000 Bag GHz pa5193e Displaying the Bandwidth Value 1 Display the bandwidth value by pressing the BW DISPLAY on OFF softkey until ON is displayed on the softkey When this softkey is set to the ON position the measured bandwidth valueis displayed in the upper left corner of the display to the right of the bandwidth Pass Wide N arrow message This value changes as the analyzer continues measuring the bandwidth The bandwidth val
193. atch Esp reverse load match E n 11 reverse source match Esp forward load match E c 22 For a fixture TRL can eliminatethe effects of the fixture s loss and length but does not completely remove the effects due to the mismatch of the fixture NOTE Because the TRL techniquerelies on the characteristic impedance of transmission lines the mathematically equivalent method LRM for line reflect match may be substituted for TRL Since a well matched termination is in essence an infinitely long transmission line it is well suited for low RF frequency calibrations Achieving a long line standard for low frequencies is often times physically impossible 7 69 Operating Concepts TRL LRM Calibration Improving Raw Source Match and Load Match for TRL LRM Calibration A technique that can be used to improve the raw test port mismatch is to add high quality fixed attenuators The effective match of the system is improved because the fixed attenuators usually have a return loss that is better than that of the network analyzer Additionally the attenuators provide some isolation of reflected signals The attenuators also help to minimize the difference between the port source match and load match making the error terms more equivalent With the attenuators in place the effective port match of the system is improved so that the mismatch of the fixture transition itself dominates the measurement errors after a calibration
194. ated to the A and B input ports on the analyzer 7 20 Figure 7 3 S Parameters of a Two Port Device Operating Concepts S Parameters S INCIDENT 21 FORWARD TRANSMITTED a 944 REFLECTED us 1 REFLECTED 322 PORT PORT 2 b a2 TRANSMITTED INCIDENT S42 REVERSE a b 1 321 2 say 11 A Sx b 1 S49 0 pg639d S parameters are exactly equivalent to these more common description terms requiring only that the measurements be taken with all test device ports properly terminated S Parameter Definition by aj 2 0 bjla 85 0 bia a 0 bj a a 0 Test Set Description Input reflection coefficient Forward gain Reverse Gain Output reflection coefficient Direction FWD FWD REV REV 7 21 Operating Concepts S Parameters The S Parameter Menu The S parameter menu allows you to define the input ports and test set direction for S parameter measurements The analyzer automatically switches the direction of the measurement according to the selections you made in this menu Therefore the analyzer can measure all four S parameters with a single connection The S parameter being measured is labeled at thetop left corner of the display The S parameter menu contains the following softkeys e Refl FWD S11 A R Trans FWD S21 B R Trans REV S12 A R Refl REV S22 B R ANALOG IN Aux Input CONVERSION accesses the conversion menu e INPUT
195. ating for Non Coaxial Devices Calibrating for Non Coaxial Devices The analyzer has the capability of making calibrations using the TRL LRM method TRL and LRM are implementations of the thru reflect line and line reflect match calibrations modified for the three sampler receiver architecture in the analyzer TRL Error Correction Create a User Defined TRL Calibration Kit In order to use the TRL technique the calibration standards characteristics must be entered into the analyzer s user defined calibration kit The following steps show you how to define a calibration kit to utilize a set of TRL THRU REFLECT LINE standards This example TRL kit contains the following zerolength THRU e flush short for the REFLECT standard 0 second offset e 50 ohm transmission line with 80 ps of offset delay for the LINE Modify the Standard Definitions 1 Press the following keys to start modifying the standard definitions CAL KIT MODIFY DEFINE STANDARD 2 To select a short press x1 In this example the REFLECT standard isa SHORT 3 Press the following keys SHORT MODIFY STD DEFINITION SPECIFY OFFSET OFFSET DELAY 0 STD OFFSET DONE STD DONE DEFINED 4 Todefinethe THRU LINE standard press DEFINE STANDARD DELAY THRU MODIFY STD DEFINITION SPECIFY OFFSET OFFSET DELAY 0 STD OFFSET DONE STD DONE DEFINED 5 To definethe LINE MATCH standard press DEFINE STANDARD DELAY THRU MODIFY STD DEFINITION SPECIFY OF
196. ation This calibration is only allowed for non ratioed measurements A B and R This calibration normalizes the trace to the current reference value Typically this reference value is entered to be the same as the current source power 1 Perform a power meter calibration to the desired level Refer to step A of Figure 6 4 Use 10 dBm for this example See also Power M eter M easurement Calibration on page 6 33 This provides a calibrated power referenced to the power meter to use as a receiver calibration standard or Set the analyzer test port power to the desired level 10 dBm in this example by pressing x1 This calibrates the receiver to the approximate accuracy of the source output power which is subject to the source power flatness specification 2 Makea thru connection between the points where you will connect your device under test Refer to Step B of Figure 6 4 NOTE Indude any adapters or cables that you will havein the device measurement That is connect the standard device where you will connect your device under test 6 15 Calibrating for Increased Measurement Accuracy Frequency Response Error Corrections Figure 6 4 Standard Connections for a Receiver Calibration NETWORK ANALYZER NETWORK ANALYZER POWER METER Test Port Cables Test Port Cables Possible Adapters Power Sensor Possible Adapters Step A Step B pa5164e 3 To choose a
197. ation the proper LO power level must be input to the LO port 2 43 Making Mixer Measurements Isolation Example Measurements Figure 2 34 Connections for a Mixer Isolation Measurement NETWORK ANALYZER 20 dB 50 2 Load pa564e 7 To adjust the display scale press Scale Ref AUTO SCALE The measurement results show the mixer s LO to RF isolation Figure 2 35 Example Mixer LO to RF Isolation Measurement CH1 B R log MAG 10 dB REF 45 dB tal PRm Cor START 10 000 000 MHz STOP 3 000 000 000 MHz 2 44 Making Mixer Measurements Isolation Example Measurements RF Feedthrough The procedure and equipment configuration necessary for this measurement are very similar to those of the previous LO to RF Isolation procedure with the addition of an external source to drive the mixer s LO port as we measure the mixer s RF feedthrough RF feedthrough measurements do not use the frequency offset mode 1 Select the CW LO frequency and source power from the front panel of the external source CW frequency 300 MHz Power 10 dBm 2 Initialize the analyzer by pressing Preset 3 To select the analyzer frequency range and source power press 0 This source stimulates the mixer s LO port 4 Toselect a ratio B R measurement press B R NOTE Isolation is dependent on LO power level and frequency To ensure good test results you should choose these parameters as c
198. ation Error Corrections 7 Make a thru connection between the points where you will connect your device under test NOTE Include any adapters that you will have in the device measurement That is connect the standard device to the particular connector where you will connect your device under test 8 To measure the standard when the displayed trace has settled press THRU The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the THRU softkey after it measures the calibration standard and computes the error coefficients 9 Connect impedance matched loads to PORT 1 and PORT 2 as shown in Figure 6 5 Include the adapters that you would include for your device measurement Figure 6 5 Standard Connections for a Response and Isolation Error Correction for Transmission Measurements FOR RESPONSE FOR ISOLATION Possible Adapters pa583e NOTE If you will be measuring highly reflective devices such as filters usethe test device connected to the reference plane and terminated with a load for the isolation standard 10 To help remove crosstalk noise set the analyzer as follows a Press AVERAGING ON AVERAGING FACTOR and enter at least four times more averages than desired during the device measurement b Press MORE ALTERNATE AandB toeliminate one crosstalk path 6 18 Calibrating for Increased Measurement Accuracy Frequency Response and Isolation Er
199. ats Thelist values feature in the copy menu provides tabular listings tothe display or a printer for every measured stimulus value These include limit line or limit test information if these functions are activated If limit testing is on an asterisk is listed next to any measured value that is out of limits If limit lines are on and other listed data allows sufficient space the upper limit and lower limit arelisted together with the margin by which the device data passes or fails the nearest limit 7 81 Operating Concepts Limit Line Operation If limit lines are on they are plotted with the data on a plot If limit testing is on the PASS or FAIL message is plotted and the failing portions of the trace that are a different color on the display are also a different color on the plot If limits are specified they are saved in memory with an instrument state Edit Limits Menu This menu allows you to specify limits for limit lines or limit testing and presents a table of limit values on the display Limits are defined in segments Each segment is a portion of the stimulus span Up to 22 limit segments can be specified for each channel The limit segments do not have to be entered in any particular order the analyzer automatically sorts them and lists them on the display in increasing order of start stimulus value For each segment the table lists the segment number the starting stimulus value upper
200. automatic gain control slope To set the frequency of the power sweep use CWFREQ in the stimulus menu The span of the swept power is limited to being equal toor within one of the eight pre defi ned power ranges The attenuator will not switch to a different power range while in the power sweep mode Therefore when performing a power sweep power range selection will automatically switch to the manual mode n power sweep the entered sweep time may be automatically changed if it is less than the minimum required for the current configuration number of points IF bandwidth averaging etc CW Time Sweep Seconds The CW TIME softkey turns on a sweep mode similar to an oscilloscope The analyzer is set to a single frequency and the data is displayed versus time The frequency of the CW time sweep is set with CWFREQ in the stimulus menu In this sweep mode the data is continuously sampled at precise uniform time intervals determined by the sweep time and the number of points minus 1 The entered sweep time may be automatically changed if it is less than the minimum required for the current instrument configuration In time domain using Option 010 the CW time mode data is translated to frequency domain and the x axis becomes frequency In this mode the instrument can be used as a spectrum analyzer to measure signal purity or for low frequency 1 kHz analysis of amplitude or pulse modulation signals Selecting Sweep Modes In add
201. ave been executed the analyzer switches between the test ports and begins the cyde again This type of test set switching can provide improved measurement accuracy over the hold mode and faster measurement speeds than continuous mode NOTE Fast 2 Port Calibration Accuracy For most devices the fast 2 Port Calibration method is nearly as accurate as the full 2 Port Calibration method Toaccess the test set switch functions press MORE TESTSET SW CONTINUOUS Toactivate the hold mode press MCD The analyzer will then display the softkey as TESTSET SWHOLD Toactivate the continuous mode press The analyzer will then display TESTSET SW CONTINUOUS Toenter the number of sweeps for this example 8 sweeps press The analyzer will then display the softkey as TESTSET SW 8 Sweeps 5 13 Optimizing Measurement Results Increasing Dynamic Range Increasing Dynamic Range Dynamic range is the difference between the analyzer s maxi mum allowable input level and minimum measurable power For a measurement to be valid input signals must be within these boundaries The dynamic range is affected by these factors e test port input power e test port noise floor receiver crosstalk Increase the Test Port Input Power You can increase the anal yzer s source output power so that the test device output power is at the top of the measurement range of the analyzer test port Press and enter the new source power level
202. aving Measurement Results Saving Measurement Results Files with f1and f2 File Extensions FileXX f1 produced only when FORMAT ARY on OFF isturned ON may be either binary or ASCII This file contains the formatted data in whichever format is currently displayed on the network analyzer dB phase VSWR and soforth with error correction trace math port extensions electrical delay time domain gating and smoothing applied Port extensions are really only evident if the measured parameter is phase The same type of fileis produced for Channel 2 but the file extension is f2 If dual display is on both f1 and f2 are produced In ASCII format the data appears as two columns CITIfile format If the currently selected display format is not complex data neither Smith Chart nor Polar the second column will be meaningless place holder values Files with gO File Extension FileXX g0 produced only when GRAPHICS on OFF is turned ON is a binary file containing the active measurement trace and display graticule The contents of this fileare not meant to be read in an external computer so this file is only of use in the instrument Binary Files The size of the data files is very small about one tenth the size compared to the ASCII format Binary is theformat to use when you want to store and recall instrument states on the analyzer quickly but do not need to read the data in an external computer ViewingFiles Within the Analyzer All
203. ay due tothe long electrical length of the SAW filter under test Measuring Phase Distortion This portion of the example shows you how to measure the linearity of the phase shift over a range of frequencies The analyzer allows you to measure this linearity and read it in two different ways deviation from linear phase or group delay 1 45 Making Measurements Measuring Electrical Length and Phase Distortion Deviation From Linear Phase By adding electrical length to flatten out the phase response you have removed the linear phase shift through your device The deviation from linear phase shift through your device is all that remains 1 Follow the procedure in Measuring Electrical Length on page 1 43 2 Toincrease the scale resolution press Scale Ref SCALE DIV and turn the front panel knob or enter a value from the front panel keypad 3 Tousethe marker statistics to measure the maximum peak to peak deviation from linear phase press MKR MODE MENU STATSON 4 Activate and adjust the electrical delay to obtain a minimum peak to peak value NOTE It is possible to use delta markers to measure peak to peak deviation in only one portion of the trace See To Calculate the Statistics of the Measurement Data on page 1 42 Figure 1 36 Deviation From Linear Phase Example Measurement CH1 S24 phase 500 m REF 171 1 170 4 A 134 000 OGO MHz SCALE RV MR V
204. ble 3 3 Windowing improves the dynamic range of a time domain measurement by filtering the frequency domain data prior to converting it to the time domain producing an impulse stimulus that has lower sidelobes This makes it much easier to see time domain responses that are very different in magnitude The sidelobe reduction is achieved however at the expense of increased impulse width The effect of windowing on the step stimulus low pass mode only is a reduction of overshoot and ringing at the expense of increased rise time To select a window press TRANSFORM MENU WINDOW A menu is presented that allows the selection of three window types see Table 3 3 3 27 Making Time Domain Measurements Windowing Table 3 3 Impulse Width Sidelobe Level and Windowing Values Window Type Impulse Sidelobe Low Pass Impulse Step Sidelobe Step Rise Time Level Width 5046 Level 10 90 Minimum 13 dB 0 60 F req Span 21 dB 0 45 F req Span Normal 44 dB 0 98 F req Span 60 dB 0 99 F req Span Maximum 75 dB 1 39 F req Span 70 dB 1 48 F req Span NOTE The bandpass mode simulates an impulse stimulus Bandpass impulse width is twice that of low pass impulse width The bandpass impulse sidelobe levels are the same as low pass impulse sidelobe levels Choose one of the three window shapes listed or use the knob to select any windowing pulse width or rise time for a step stimulus between the softkey
205. c Calibration ECal Investigating the Calibration Results Using the ECal Service Menu CAUTION The confidence check described in the previous section displays the E Cal data of a single state This confidence state is a calibrated standard not used during ECal It is provided to give an independent assessment of the quality of a calibration In the Ecal Service menu you may also display each of the calibration standards which are used during an ECal calibration along with the analyzer s measurement of those standards Y ou may nctice a difference in measurement results when comparing E Cal confidence state data and ECal standard state data This result may be related to certain measurement errors with the network analyzer system which add uncertainty to measurement results More detailed information regarding measurement uncertainty is documented in the Determining System M easurement U ncertainties chapter of the network analyzer s reference guide Additional information on improving your measurements can be found in Chapter 5 Optimizing Measurement Results Using the ECal Service menu is not a standard part of the ECal procedure It is a tool to allow you to identify problems in the calibration equipment cables connectors or procedures The Confidence Check menu supports the comparison of the measured data versus the module s premeasured calibration data for the confidence state The ECal Service menu supports the comparison of the
206. calibration For a good calibration measurement there should be no significant difference between the traces see Figure 6 24 To Perform the Confidence Check NOTE A confidence check is only valid after an ECal has been performed 1 Press Cal ECal MENU CONFIGURE 2 Press MODULE A b until the correct module A or B is selected 3 Select CONFIDENCE CHECK to display the confidence check and the E Cal Confidence M enu 4 Press PARAMETER until the S parameter that you want to view is displayed Pressing the PARAMETER softkey toggles between the S11 S21 S12 and S22 calibration traces The confidence check will only display the S parameter calibration data for which you calibrated Uncalibrated S parameter data traces are invalid The memory trace still displays the module s factory premeasured trace For example If you performed You can view A 1 port calibration Only one calibrated S parameter 111 PORT S22 I PORT An enhanced response calibration Only two calibrated S parameters one at a time e 117 S21ENH RESP e S22 S12 ENH RESP A full 2 port calibration All four calibrated S parameters one at atime e FULL 2 PORT 6 67 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal 5 Press TRACE TYPE until the calibration confidence check trace that you want to view is displayed Pressing the TRACE TYPE softkey togg
207. calling a file Formatting a disk Solving problems with saving or recalling files Printing Plotting and Saving Measurement Results Printing or Plotting Your Measurement Results Printing or Plotting Your Measurement Results You can print your measurement results to the following peripherals printers with GPIB interfaces printers with parallel interfaces printers with serial interfaces You can plot your measurement results to the following peripherals HPGL compatible printers with GPIB interfaces HPGL compatible printers with parallel interfaces plotters with GPIB interfaces plotters with parallel interfaces plotters with serial interfaces Most Hewlett Packard desktop printers and plotters are compatible with the analyzer For a list of recommended peripherals refer to the configuration guide for your analyzer The following Web site also contains a link tothe configuration guide www agilent com find 8753 A printer compatibility guide an up to date list of printers that are compatible with the network analyzer can be found at the following Web site www agilent com find pcg 4 3 Printing Plotting and Saving Measurement R esults Configuring a Print Function Configuring a Print Function All copy configuration settings are stored in non volatile memory Therefore they are not affected if you press or switch off the analyzer power 1 Connect the printer to the interface port Figure 4 1 P
208. can create subprograms for a larger test sequence You can also cascade sequences to extend the length of test sequences to greater than 200 lines In this example you are shown two sequences that have been cascaded You can dothis by having the last command in sequence 1 call sequence position 2 regardless of the sequence title Because sequences are identified by position not title the call operation will always go to the sequence loaded into the given position 1 Tocreate the example multiple sequences press NEW SEQ MODIFY SEQ SEQUENCE 1SEQ1 DO SEQUENCE SEQUENCE 2 DONE SEQ MODIFY NEW SEQ MODIFY SEQ SEQUENCE 2SEQ2 Trans FWD S21 B R LOG MAG AUTOSCALE DONE SEQ MODIFY 1 113 Making Measurements Using Test Sequencing to Test a Device The following sequences will be created SEQUENCE SEQ1 Start of Sequence CENTER 134 M u SPAN 50 M u DO SEQUENCE SEQUENCE 2 SEQUENCE SEQ2 Start of Sequence Trans FWD S21 B R LOG MAG SCALE DIV AUTO SCALE You can extend this process of calling the next sequence from the last line of the present sequence to 6 internal sequences or an unlimited number of externally stored sequences 2 Torun both sequences press SEQUENCE 1SEQ1 Loop Counter Example Sequence This example shows you the basic steps necessary for constructing a looping structure within a test sequence A typical application of this loop counter structureis for repeatin
209. ce Reference Port 1 Port 2 pa597e 4 Perform a full 2 port calibration between ports 1 and 2 using calibration standards appropriate for the connector type at port 1 the connector type for adapter A1 Save the calibration by selecting SAVE STATE Namethe file PORT1 5 Connect adapter A3 to adapter A1 on port 1 as shown in Figure 6 16 6 43 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Figure 6 16 Two Port Cal Set 2 NETWORK ANALYZER Reference Reference Port 1 Port 2 pa599e 6 Perform a full 2 port calibration between ports 1 and 2 using calibration standards appropriate for the connector type at port 2 the connector type for adapter A2 Save the calibration by selecting Save Recall SAVE STATE Namethe file PORT2 NOTE In the following steps calibration data is recalled not instrument states 7 Press MORE ADAPTER REMOVAL RECALL CAL SETS 8 Turn the knob to select the file that contains the port 1 calibration data where adapter A3 was on port 2 9 Press RECALL CAL PORT 1 10 Turn the knob to select the file that contains the port 1 calibration data where adapter A3 was on port 1 ll Press RECALL CAL PORT 2 RETURN 12 Press ADAPTER DELAY Enter the delay value of the adapter from step 2f Select the appropriate type ADAPTER COAX or ADAPTER WAVEGUIDE 13 Press REMOVE ADAPTER to complete the technique for calculating the new coeffiecients and overwrite
210. ce a normalized trace that represents gain compression perform either step 5 or step 6 Step 5 uses trace math and step 6 uses uncoupled channels and the display function DI D2to D2 ON 5 Press DATA MEMORY DATA MEM to produce a normalized trace 6 To produce a normalized trace perform the following steps Press DUAL QUAD SETUP and select DUAL CHANNEL ON to view both channels simultaneously Press Trans FWD S21 B R To uncouple the channel stimulus so that the channel power will be uncoupled press COUPLED CH OFF This will allow you to separately increase the power for channel 2 and channel 1 so that you can observe the gain compression on channel 2 while channel 1 remains unchanged To display the ratio of channel 2 data to channel 1 data on the channel 2 display press DISPLAY MORE D2 D1toD20N This produces a trace that represents gain compression onl y 7 Press MARKER 1 and position the marker at approximately mid span 8 Press Scale Ref SCALE DIV to changethe scaleto 1 dB per division 9 Press Power 10 I ncrease the power until you observe approximately 1 dB of compression on channel 2 using the step keys or the front panel knob 11 To locate the worst case point on the trace press Marker Search SEARCH MIN 1 60 Making Measurements Measuring Amplifiers Figure 1 49 Gain Compression Using Linear Sweep and D2 D1to D2 ON CH1 S2 log MAG 10 dB REF dB 1 19 723 dB 1 boa eda MHz
211. ceiver to a synthesized CW input signal at a precisely specified frequency All phase lock routines are bypassed increasing sweep speed significantly The external source must be synthesized and must drive the analyzer s external frequency reference The analyzer s internal source frequency is not accurate and the internal source should not be used in the tuned receiver mode 7 85 Operating Concepts Knowing the Instrument Modes Usingthe analyzer s tuned receiver mode is useful for automated test applications where an external synthesized source is available and applications where speed is important Although the tuned receiver mode can function in all sweep types it is typically used in CW applications Typical test setup 1 Activate the tuned receiver mode by pressing INSTRUMENT MODE TUNED RECEIVER 2 To perform a CW measurement using the tuned receiver mode connect the equipment as shown in Figure 7 47 Figure 7 47 Typical Test Setup for Tuned Receiver Mode SYNTHESIZED SWEEPER 10MHz REF EXT a REF IN NETWORK ANALYZER Sooo oS 0000 o00000 0000 ooo 000 o a o 2o 0000 2 uns 0000 Q I 0000 0000 000 6 oo ogg 0D QD 0D 00 00 888 o 000 ooo coo 0000 c3 DUT pg66e Tuned Receiver Mode In Depth Description If you press INSTRUMENT MODE TUNED RECEIVER theanalyzer receiver operates independently of any signa
212. cer RR cee dateis bined eeed iat XY APP SPERA 5 12 Tollse Fast 2 P ort Callbrauol asoxaacexqeteebrre4wte C EXpPEEZQUYATGeqoweb EQ Pda 5 12 Increasing Dynamic Ranger peices pacekesribe bra ACER GU E XAR 4 RGrbgnHE d PE ded 5 14 Contents Increasethe Test Port Input POWEr 2 cccceethdee RR ERE ERERRRERRHRRTERTYRERERRPRRE 5 14 Reducethe Receiver Noise FIOO iossusseskaee uad dee a Pees nee RAw p OR RE EA ERE 5 14 Reduce the Receiver Crosstalk 00 c ete 5 14 REONE NOSE iu cis ERE aed Spb e ERE HSE deed IS Oe dee GOES d hee oye Vb de 5 15 To Achats AVE SONY cuieprd Re EPRESERE VER ARERPETYADANERPEYNG d dais ER dees 5 15 Tothange system BandWidth uou pae RP PREGXAU REC ac PEG M RI PI RIPCRER 5 15 Reduong Receiver Crosstalk i4escewe Cobo wiGia RERO KA piri ii kiN E iE 5 16 PIONS Recall TIG usd e de erp eee EG EORR eae POP ER RE od e EQ ERNE ORME RIA eK 5 17 Understanding Spur AVOIGSNGCE ui Lebe Rid remer isi EPR EE AT A ERRRSK EYE EGER 5 17 6 Calibrating for Increased Measurement Accuracy How tese This CNS 43 ax ao poe ced biete pex PE ee PXqpEP3chev qve rbiwve rr 6 2 OEFOCBIEEIDET i i ck IE EAR EER EM EMER E RIAL IIR ERR EE RR CROCE 6 3 Calibration Considerations nia asad a die Ee 4 Goda de PEOR K de OE ROI o dd ww be 6 4 Measurement Pal amelers iis set iide bee ARAS EGE REA ROG EERE o C d p Ra den 6 4 Device Measurements saa p05 0054 0 EXEC Ve do Ce dO ORE UC OP ee P C dedos 6 4 Clarity TypeN Connector SEX iocsesuatererekbeteLberd
213. ch on bilateral devices 54 l port Reflection of any Directivity source Short open and load one port device or match frequency or ECal module well terminated response two port device S2 l port Reflection of any Directivity source Short open and load one port device or match frequency or ECal module well terminated response two port device Full 2 port Transmission or Directivity source Short open load and reflection of highest match load match thru 2 loads for accuracy for two port isolation frequency isolation or ECal devices response forward and module reverse TRL LRM Transmission or Directivity isolation Thru reflect line or reflection in frequency response line reflect match or noncoaxial forward and reverse thru reflect match environment such as in a fixture or on wafer NOTE Response calibration is not as accurate as other calibration methods Calibrating for Increased Measurement Accuracy Frequency Response Error Corrections Frequency Response Error Corrections You can remove the frequency response of the test setup for the following measurements e reflection measurements e transmission measurements e combined reflection and transmission measurements Response Error Correction for Reflection Measurements 1 Press Preset 2 Select the type of measurement you want to make OV If you want to make a reflection measurement on PORT 1 in the forward direction S11 lea
214. ch the standard applies and defined as coax or waveguide The SPECIFY OFFSET softkey accesses the specify offset menu described next The LABEL STD softkey allows you to define a distinct label for each standard so that the analyzer can prompt you with explicit standard labels during calibration such as SHORT The function is similar to defining a display title except that the label is limited to ten characters After each standard is defined induding offsets the STD DONE DEFINED softkey will terminate the standard definition Specify Offset Menu The specify offset menu allows additional specifications for a user defined standard Features specified in this menu are common to all five types of standards Offsets may be specified with any standard type This means defining a uniform length of transmission lineto exist between the standard being defined and the actual measurement plane Example a waveguide short circuit terminator offset by a short length of waveguide For reflection standards the offset is assumed to be between the measurement plane and the terminating element of the standard one way only For transmission standards the offset is assumed to exist between the two reference planes in effect the offset is the thru For both reflection and transmission the offset is entered as a one way offset Three characteristics of the offset can be defined its delay length loss and impedance In addition the freque
215. chart When CAL ZO LINE ZO is selected the values entered for SET ZO under menu and OFFSET ZO within the define standard menu are ignored CAL ZO SYSTEM ZO is selected when the desired measurement impedance differs from the impedance of the line standard This requires a knowledge of the exact value of the Zp of the line The system reference impedance is set using SET ZO under the calibration menu The actual impedance of the lineis set by entering the real part of theline impedance as the OFFSET ZO within the define standard menu For example if the line was known to have a characteristic impedance of 51 Q OFFSET ZO 51 Q it could still be used to calibrate for a 50 Q measurement SET ZO 50 Q After a calibration all measurements would be referenced to 50 Q instead of 51 Q When the line standard is remeasured the center of the Smith chart is at the current value of SET ZO in this case 50 Q Since only one value of offset Zo can be selected for the line standard the value of Zo should be a constant value over the frequency range of interest in order to be meaningful The location of the reference planeis determined by the selection of SET REF THRU and SET REF REFLECT By default the reference plane is set with the thru standard which must have a known insertion phase or electrical length If a non zero length thru is specified to have zero delay the reference plane will be established in the middle of the thru The reflect stan
216. cludes graticules annotation and softkey labels If user display graphics are written these are also stored in display memory When a print or plot is made the information is taken from display memory Thedisplay is updated frequently and synchronously with the data processing operations Operating Concepts Output Power Output Power Source output power can be set over a range of 5 to 20 dBm 5 to 18 dBm for Option 006 The power setting can be combined with the test set step attenuator setting for a wide output power range at the test ports The actual test power range depends on the test set NOTE After measurement calibration you can change the power within a range i e without changing the step attenuator setting and still maintain nearly full accuracy n some cases better accuracy can be achieved by changing the power within a range It can be useful to set different power levels for calibration and measurement to minimize the effects of sampler compression or noise floor If you decideto changethe step attenuator setting the calibration accuracy is degraded and accuracy is nolonger specified H owever the analyzer leaves the correction on The annotation cA will be displayed whenever you change the power after calibration Power Coupling Options There are two methods you can use to couple and uncouple power levels with the analyzer channel coupling port coupling By uncoupling the channel powers you
217. computer sends commands or instructions to and receives data from the analyzer All of the capabilities available from the analyzer front panel can be used in this remote operation mode except for control of the power line switch and some internal tests Pass Control Mode The USE PASS CONTROL softkey activates the third mode of GPIB operation the pass control mode n an automated system with a computer controller the controller can pass control of the bus tothe analyzer on request from the analyzer The analyzer is then the controller of the peripherals and can direct them to plot print or store without going through the computer When the peripheral operation is complete control is passed back to the computer Only one controller can be active at a time The computer remains the system controller and can regain control at any time Preset does not affect the selected controller mode but cycling the power returns the analyzer to talker listener mode Information on compatible peripherals is provided in the Options and Accessories chapter of the reference guide 7 78 Operating Concepts GPIB Operation Address Menu This menu can be accessed by pressing the SET ADDRESS softkey within the GPIB menu In communications through the General Purpose Interface Bus GPIB each instrument on the bus is identified by a GPIB address This decimal based address code must be different for each instrument on the bus This menu lets you
218. corresponds to the actual GPIB address of the peripheral The procedure is explained earlier in this chapter Make sure that the analyzer is in system controller mode by pressing SYSTEM CONTROLLER if the analyzer is not connected to an external controller Otherwise the analyzer must be in the pass control mode Substitute the interface cable Substitute a different printer or plotter 4 33 Printing Plotting and Saving Measurement Results Saving and Recalling Instrument States Saving and Recalling Instrument States Places Where You Can Save e analyzer internal memory floppy disk using the analyzer s internal disk drive e floppy disk using an external disk drive e IBM compatible personal computer using GPIB mnemonics What You Can Save to the Analyzer s Internal Memory The number of registers that the analyzer allows you to save depends on the size of associated error correction sets and memory traces H owever the maximum number of registers that can be saved to internal memory is 31 Refer to the Preset State and M emory Allocation chapter of the reference guide for further information You can save instrument states in the analyzer internal memory along with the following list of analyzer settings The default file names are REG 01 31 error corrections on channels 1 and 2 displayed memory trace print plot definitions measurement setup frequency range number of points sweep time output
219. cs of Measurement Data CH1 S log MAG 20 dB REF dB 2 3 7131 dB 21 g 26 04 ada MHz PRm AREF 1 hean 18 931 5 dB MARKER 2 dev 1 5481 dB 26 304 MHz p p 5 6718 dB CENTER 125 8000 8880 MHz SPAN 120 000 808 MHz 1 42 Making Measurements Measuring Electrical Length and Phase Distortion Measuring Electrical Length and Phase Distortion Electrical Length The analyzer mathematically implements a function similar to the mechanical line stretchers of earlier analyzers This feature simulates a variable length lossless transmission line which you can add to or remove from the anal yzer s receiver input to compensate for interconnecti ng cables etc In this example the electronic line stretcher measures the electrical length of a SAW filter Phase Distortion Theanalyzer allows you to measurethe linearity of the phase shift through a device over a range of frequencies and the analyzer can express it in two different ways deviation from linear phase group delay Measuring Electrical Length 1 Connect your test device as shown in Figure 1 33 Figure 1 33 Device Connections for Measuring Electrical Length NETWORK ANALYZER pa53e 2 Press and choose the measurement settings For this example the measurement settings include reducing the frequency span to eliminate under sampl ed phase response Press the following keys as shown Trans FWD S21 B
220. ct reflection coefficient for the first discontinuity p 0 50 H owever the second discontinuity appears as a 37 5 reflection p 0 375 because only some the incident voltage reached the second discontinuity and some of that reflected energy is reflected off the first discontinuity as it returns For two discrete discontinuities the apparent reflection of the second discontinuity is appears as approximately p 1 p p Where p is the apparent reflection of the second discontinuity p is the reflection of the first discontinuity and p is the reflection of the second discontinuity NOTE This example assumes a lossless transmission line Real transmission lines with non zero loss attenuate signals as a function of the distance from the reference plane As an example of masking due to line loss consider the time domain response of a 3 dB attenuator and a short circuit The impulse response log magnitude format of the short circuit aloneis a return loss of 0 dB as shown in Figure 3 21a When the short circuit is placed at the end of the 3 dB attenuator the return loss is 6 dB as shown in Figure 3 21b This value actually represents the forward and return path loss through the attenuator and illustrates how a lossy network can affect the responses that follow it Figure 3 21 Masking Example CH1 S44 10g MAG 2 dB REF 000 dB 0 daB CH1 S log MAG e dB REF 000 dB i 6 0724 dB wa m D JMAR ER ol
221. cted to the B input does not apply tothe HP Agilent 85044A B T R test sets The HP Agilent 85046A B and H P Agilent 85047A S parameter test sets contain the hardware required to make simultaneous transmission and reflection measurements in both the forward and reverse directions An RF path switch in the test set allows reverse measurements to be made without changing the connections to the test device Test Set Step Attenuator The step attenuator contained in the test set is used to adjust the power level tothe DUT without changing the level of the incident power in the reference path The attenuator in the 85046A B or 85047A test set is controlled from the front panel of the analyzer using the ATTENUATOR PORT 1 or ATTENUATOR PORT 2 softkeys located in the menu TheReceiver Block The receiver block contains three sampler mixers for the R A and B inputs The signals are sampled and mixed to produce a 4 kHz IF intermediate frequency A multiplexer sequentially directs each of the three IF signals to the ADC analog to digital converter where it is converted from an analog toa digital signal The signals are then measured and processed for viewing on the display Both amplitude and phase information are measured simultaneously regardless of what is displayed on the analyzer The Microprocessor A microprocessor takes the raw data and performs all the required error correction trace math formatting scaling averaging and marker op
222. ctivate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE 2 To movethe pointer symbol 2 on the analyzer display to the segment you wish to modify press SEGMENT lt gt or repeatedly OR SEGMENT and enter the segment number followed by xt 3 To change the upper limit for example 20 of a limit line press EDIT UPPER LIMIT DONE Deleting Limit Segments 1 To access the limits menu and activate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE 2 To movethe pointer symbol 2 on the analyzer display to the segment you wish to delete press SEGMENT lt gt or Q repeatedly OR SEGMENT and enter the segment number followed by x1 3 To delete the segment that you have selected with the pointer symbol press DELETE Running a Limit Test 1 To access the limits menu and activate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE Reviewing the Limit Line Segments Thelimit table data that you have previously entered is shown on the analyzer display Toverify that each segment in your limits table is correct review the entries by pressing SEGMENT lt gt and C5 To modify an incorrect entry refer to the Editing Limit Segments procedure located earlier in this section 1 77 Making Measurements Using Limit Lines to Test a Device Activating the Limit Test To activate the limit test and the beep fail indicator
223. ctory equipped with a remote programming interface using the General Purpose I nterface Bus GPIB This enables communication between the analyzer and a controlling computer as well as other peripheral devices This menu indicates the present GPIB controller mode of the analyzer Three GPIB modes are possible system controller talker listener and pass control 7 77 Operating Concepts GPIB Operation GPIB STATUS Indicators When the analyzer is connected to other instruments over GPIB the GPIB STATUS indicators in the instrument state function block light up to display the current status of the analyzer R remote operation L listen mode T talk mode S service request SRQ asserted by the analyzer System Controller Mode The SYSTEM CONTROLLER softkey activates the system controller mode When in this mode the analyzer can use GPIB to control compatible peripherals without the use of an external computer It can output measurement results directly to a compatible printer or plotter store instrument states using a compatible disk drive or control a power meter for performing service routines The power meter calibration function requires system controller or pass control mode Talker Listener Mode The TALKER LISTENER softkey activates the talker listener mode which is the mode of operation most often used In this mode a computer controller communicates with the analyzer and other compatible peripherals over the bus The
224. cy can be determined from the following equation receiver frequency 800 M Hz LO frequency 600 MHz 200 MHz The measurements setup diagram is shown in Figure 2 30 2 39 Making Mixer Measurements Conversion Compression Using the Frequency Offset Mode Figure 2 30 Measurement Setup Diagram Shown on Analyzer Display NETWORK ANALYZER FREQ OFFS ON off LO MENU DOWN CONVERTER I UP CONVERTER RF LO CW 200 MHz RF LO CW 800 MHz VIEW MEASURE 600 MHz 13 dBm RETURN pa560e 12 To view the mixer s output power as a function of its input power press VIEW MEASURE 13 To set up an active marker to search for the 1 dB compression point of the mixer press Scale Hef AUTO SCALE Marker Search SEARCH MAX 14 Press MKR ZERO Marker Search TARGET The measurement results show the mixer s 1 dB compression point By changing the target value you can easily locate other compression points for example 0 5 dB 3 dB SeeFigure 2 31 15 Read the compressed power on by turning marker A off AMODE MENU AMODE OFF 2 40 Making Mixer Measurements Conversion Compression Using the Frequency Offset Mode Figure 2 31 Example Swept Power Conversion Compression Measurement CH1 RM log MAG 1 dB REF 10 dB 1 9949 dB eal 14 9 dBm PRM AREF a TARGET VAWUE 1 dB t i Ofs lt START 10 0 dBm CW 800 000 000 MHz STOP 10 0 d
225. d according to the following formula o Length meters Freq MHz x 1 20083 Once the linear portion of the test device s phase has been removed the equivalent length of the lossless transmission line can be read out in the active marker area If the average relative permittivity e of the test device is known over the frequency span the length calculation can be adjusted to indicate the actual length of the test device more closely This can be done by entering the relative velocity factor for the test device using the calibrate more menu The relative velocity factor for a given dielectric can be calculated by 1 Velocity Factor Fe assuming a relative permeability of 1 7 33 Operating Concepts Noise Reduction Techniques Noise Reduction Techniques The key is used to access three different noise reduction techniques sweep to sweep averaging display smoothing and variable IF bandwidth All of these can be used simultaneously Averaging and smoothing can be set independently for each channel and thelF bandwidth can be set independently if the stimulus is uncoupled Averaging Averaging computes each data point based on an exponential average of consecutive sweeps weighted by a user specified averaging factor Each new sweep is averaged into the trace until the total number of sweeps is equal to the averaging factor for a fully averaged trace Each point on the trace
226. d direction S254 S11 press Trans FWD S21 B R 1 If you want to make measurements in the reverse direction 515 S22 press Trans REV S12 A R Set any measurement parameters that you want for the device measurement power format number of points or IF bandwidth To access the measurement correction menus press Cal If your calibration kit is different than the kit specified under the CAL KIT softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in the displayed menu refer to Modifying Calibration Kits on page 7 56 To select the correction type press CALIBRATE MENU ENHANCED RESPONSE and select the correction type 6 22 Calibrating for Increased Measurement Accuracy Enhanced Frequency Response Error Correction L1 If you want to make measurements in the forward direction press 11 S21 ENH RESP T If you want to make measurements in the reverse direction press 22 S12 ENH RESP 7 Connect a shielded open circuit to PORT 1 or PORT 2 for reverse measurements NOTE Include any adapters that you will have in the device measurement That is connect the standard tothe particular connector where you will connect your device under test Figure 6 7 Standard Connections for Enhanced Response Calibration FOR REFLECTION FOR TRANSMISSION FOR ISOLATION E pott 4 p 1 i Possible Open Shor
227. d ee Rie ees Ie Re eee REED 5 4 Terperadare DING auia bia apt 9 3 PEU Ieee Pede X aed De Ue Ced e Dae dd ed dob me bacio d 5 5 Frequency DIO eiset sebbespbCERis RP Reed ti SS eee eee e se die bee Pe dd adds 5 5 Perro mance Vert cd DIT 944 pckeww REG CEP Xd PEU ER ER PIER OR HERE Fa Eq Te P EF 5 5 Reference Plane and Port Extensions 000 eee eene 5 5 Making Accurate Measurements of Electrically Long Devices 00000 cee eeee 5 7 The Cause of Measurement Problems 6 cesueecew ew ee eee ew rh ERR 5 7 Tolmprove Measurement Results xsisaciertadRieqe tniii in rke Ri Pp nda 5 7 Increasing Sweep Speed jac tice eeidw be wwh abe dee ERHOREOGRKREELGDE Es SER ee tae EG OR 5 9 T atlssSwept LISC MOIS c250Gi adobe d sd adhe God ede bob ERI EEde PER REED bERd 5 9 To Decresce the Frequency Spall scesxed Nuikieri eX Ri EHE AREA Ris dA ddi RR 5 10 ToSet the Auto Sweep Time Mode si ccccevieabee sei REG rEERES REG a PEG d 5 11 To Widen the System Bandwidth irisiinisirirsinisromiira i EERRREER RE ER ET 5 11 To Reduce the Averaging Factor iissaaxudetkkuerX ebbrvaerXg besEx4A Ek dea 5 11 To Reduce the Number of Measurement Points llle eee eee eee 5 11 Taser rhe Swebp TVDE os ska cde tie EEES EORR Gee REPE LEE Snorer deae e qae pde 5 11 To View a Single Measurement Channel 0 02 cece eee eee 5 12 To Acdivatet hop Sweep Mode ci a 0 ives sid woe Sea Nd ee des BIS he dd eae dee b 5 12 TOUSS External Callbrallom secp os
228. d not follow the order in this example NOTE You can save or store the error correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving M easurement Results for procedures 14 This completes the one port correction for reflection measurements You can connect and measure your device under test 6 28 Calibrating for Increased Measurement Accuracy Full Two Port Error Correction Full Two Port Error Correction removes directivity errors of the test setup in forward and reverse directions removes source match errors of the test setup in forward and reverse directions removes load match errors of thetest setup in forward and reverse directions removes isolation errors of the test setup in forward and reverse directions optional removes frequency response of the test setup in forward and reverse directions NOTE This is the most accurate error correction procedure Sincethe analyzer takes both forward and reverse sweeps to update one measurement trace this procedure takes more time than the other correction procedures Set any measurement parameters that you want for the device measurement power format number of points or IF bandwidth To access the measurement correction menus press If your calibration kit is different than the kit specified under the CAL KIT softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in
229. d that their output power is switched on 2 24 Making Mixer Measurements Fixed IF Mixer Measurements NOTE You may have to consult the user s guide of the external source being used to determine how to set the source to receive SCPI commands 3 Besureto connect the 10 MHz reference signals of the external sources tothe EXT REF connector on the rear panel of the analyzer a BNC tee must be used NOTE If the 10 MHz reference signals of the external sources are connected together then it will only be necessary to connect one reference signal from one of the sources to the EXT REF connector of the analyzer Figure 2 21 Connections for a Response Calibration NETWORK ANALYZER tret Ext Reference In Ext Reference Out 21 6 dB External External RF Source LO Source pa545e NOTE To enter the following sequence commands that require titling an external keyboard may be used for convenience 4 Press the following keys on the analyzer to create sequence 1 NEW SEQ MODIFY SEQ SEQUENCE 1 SEQ1 Presetting the Instrument Save Recall SELECT DISK INTERNAL MEMORY RETURN Selec the preset state RECALL STATE 2 25 Making Mixer Measurements Fixed IF Mixer Measurements Putting the Analyzer into Tuned Receiver Mode SYSTEM CONTROLLER INSTRUMENT MODE TUNED RECEIVER Setting Up a Frequency List Sweep of 26 Points SWEEP TYPE MENU EDIT LIST ADD START STOP NUMBER OF POINTS DONE DONE LIST FREQ Performing a Response Cal
230. d within the specify class menu e 11A allows you to enter the standard numbers for the first class required for an S44 1 port calibration For default calibration kits this is the open e 11B allows you to enter the standard numbers for the second dass required for an S11 1 port calibration For default calibration kits this is the short e S11C allows you to enter the standard numbers for the third class required for an S14 1 port calibration For default calibration kits this is the load e S22A allows you to enter the standard numbers for the first class required for an S5 1 port calibration For default calibration kits this is the open S22B allows you to enter the standard numbers for the second dass required for an S gt 1 port calibration For default calibration kits this is the short e S22C allows you to enter the standard numbers for the third class required for an S55 1 port calibration For default calibration kits this is the load FWD TRANS allows you to enter the standard numbers for the forward transmission thru calibration For default calibration kits this is thethru REV TRANS allows you to enter the standard numbers for the reverse transmissi on thru calibration For default calibration kits this is the thru e FWD MATCH allows you to enter the standard numbers for the forward match thru calibration For default calibration kits this is the thru e REV MATCH allows you to
231. dard may be used to set the reference plane instead of the thru provided the phase response offset delay reactance values and standard type of the reflect standard is known and is specified in the calibration kit definition 7 75 Operating Concepts TRL LRM Calibration NOTE 7 76 Dispersion Effects Dispersion occurs when a transmission medium exhibits a variable propagation or phase velocity as a function of frequency Theresult of dispersion is a non linear phase shift versus frequency which leads to a group delay which is not constant Fortunately the TRL calibration technique accounts for dispersive effects of the test fixture up tothe calibration plane provided that 1 Thethru zero or non zero length is defined as having zero electrical length and is used to set the reference plane SET REF THRU 2 Thetransmission lines used as calibration standards have identical dispersion characteristics i e identical height width and relative dielectric constant When a non zero length thru is used to set the reference plane it should be defined as having zero length in the TRL standards definition even though it has physical length The actual electrical length of the thru standard must then be subtracted from the actual electrical length of each line standard in theTRL calibration kit definition The device must then be mounted between two short lengths of transmission line so that each length is exactly one half of the
232. dbREREP Ra bapor oa EACE a RERA C eC ER RC 7 3 The Built Synthesized SOUTE ee ics a5 iad eb ER Ne redken iaee DRE CEE Qa PER E 7 4 ie earn ee tee cece ee eer dor ICE Ie ee er eee ad 7 4 The REVA BIGEK ud eraxadrbqeYpera ete gag nq Te PX q EPqqP EK dp pqqve 24 4x 7 4 THe MICFODUOCBESDE auaxauua e CER aR REOR Rr Rc oe RENE EROR ieee CREER RA 7 4 Regum ed Peripheral EQUIPMENT iuixsesex nbkxr amp ke3XdembXxGREPEP dee tu Kinabii RS 7 5 PIOUBSSIHO 2i dis pbrEERCERRSUL ARR CIRRS POE RT C HAGERqe CERE E NE A ei LEE oe aess 7 6 Processing Details 44x ex d pete RPRTd PREXQPET ERG QV PRSpI E QVI REORPP EQ d 7 7 DULDUt PONB uud xcbesadckbieb E RERDE ME EA br ES ia PRG ENG ERAGE PARS 7 10 Power C DUDIB DB DIS 44949 peu SKK due DEKE ORE dra Y P GC ORE OO POE CI Ne ADORED 7 10 SWED TIME Lies ei PERDU reiii e nRa RP MERERI RO WPRPU END CHEERERYA T RERE S 7 11 Manual Sweep Time MOJE sc ckiew pct nee ein Fear dodo ee TQpkDEPPbQqerEd dea qXq 3s 7 11 Auta Sweep Toe MOJE 126 e dws es be EOE RE RR RETR oe EREEREER DN REEERE see aes 7 11 Pium Sweep THN ie iad enh S294 ea De dw bode ated we xd 7 11 Source Attenuater Switch PPOEECDOIT suk ci gae ARE e ERE ie Ee RAM dixic RA d Ede 7 13 Allowing Repetitive Switching of the Attenuator 0 00 cee es 7 13 Chahine Stimulus COUBING 22sec kt eeeche wee shi REESE IDICERERE RAS GERE ER AK EGER 7 14 Sweep TUVDES prar ei SARTRE OD PRR OTIS v dO a PRE TAK PREC PME red A 7 15 Linear Frequency Sweep HZ 22 6269 eteet d
233. ded Thetime domain measurement is an average of the response over the frequency range of the measurement If the frequency domain data is measured out of band the time domain measurement is also the out of band response You may with these limitations in mind chooseto use a frequency span that is wider than the test device bandwidth to achieve better resolution 3 33 Making Time Domain Measurements Resolution Range Resolution Time domain range resolution is defined as the ability to locate a single response in time If only one response is present range resolution is a measure of how dosely you can pinpoint the peak of that response The range resolution is equal to the digital resolution of the display which is the time domain span divided by the number of points on the display To get the maximum range resolution center the response on the display and reduce the time domain span The range resolution is always much finer than the response resolution see Figure 3 25 Figure 3 25 Range Resolution of a Single Discontinuity CH1 S11 Re 1 mU REF 4 mU 1 7 4215 mU hp 1 321 ns 4 Cor MARKER 1 I 1 321 ns 396 03 mm N CH1 START 1 078 ns STOP 1 505 ns pg683d 3 34 Making Time Domain Measurements Gating Gating Gating provides the flexibility of selectively removing time domain responses The remaining time domain responses can then be transfo
234. delay tg and deviation from linear phase through a linear device H owever this parameter also contains valuable information about transmission delay and distortion through a non linear device such as a mixer or frequency converter For example flat group delay corresponds to low modulation distortion that is carrier and sidebands propagate at the same rate Phase linearity and group delay are both measurements of the distortion of a transmitted signal Both measure the non linearity of a device s phase response with respect to frequency In standard vector error correction a thru delay 0 is used as a calibration standard The solution to this problem is to use a calibration mixer with very small group delay as the calibration standard An important characteristic to remember when selecting a calibration mixer is that the delay of the device should be kept as low as possible To do this select a mixer with very wide bandwidth wider bandwidth results in smaller delay The accuracy of this measurement depends on the quality of the mixer that is being used for calibration and how well this mixer has been characterized The following measurement must be performed with a broadband calibration mixer that has a known group delay The following table lists the specifications of two mixers that may be used for calibration Model Number Useful Frequency Range Group Delay ANZAC MCD 123 0 03 to 3 GHz 0 5 ns Mini Circuits ZF M 4 dc to
235. dicate product compliance with the Canadian nterference Causing Equipment Standard I CE S 001 Safety and Regulatory Information Safety Considerations Safety Considerations NOTE This instrument has been designed and tested in accordance with IEC Publication 1010 Safety Requirements for Electronics Measuring Apparatus and has been supplied in a safe condition This instruction documentation contains information and warnings which must be followed by the user to ensure safe operation and to maintain the instrument in a safe condition Safety Earth Ground WARNING This is a Safety Class product provided with a protective earthing ground incorporated in the power cord The mains plug shall only be inserted in a socket outlet provided with a protective earth contact Any interruption of the protective conductor inside or outside the instrument is likely to make the instrument dangerous Intentional interruption is prohibited CAUTION Always usethethree prong AC power cord supplied with this product Failure to ensure adequate earth grounding by not using this cord may cause product damage Before Applying Power CAUTION Install the instrument so that the ON OFF switch is readily identifiable and is easil y reached by the operator The ON OFF switch or the detachable power cord is the instrument disconnecting device It disconnects the mains circuits from the mains supply before other parts of the instru
236. e Frequency Band 3 to be deleted by pressing FREQUENCY BAND DELETE 3 Repeat step 2 until you have deleted the required frequency bands from the list 4 f you need to delete all of the frequency bands you can delete them all by pressing CLEAR LIST When this softkey is pressed you will be asked to confirm that you want to delete all of the frequency bands from the list 5 After you have finished deleting the frequency bands you can return tothe ripple test menu by pressing DONE Running the Ripple Test Once the list of ripple limits has been set up you are ready to run the ripple test From the Ripple Test Menu you can Start and stop the ripple test e Display and hide the ripple test limit lines Select a frequency band and display its ripple measurement in two ways m the absolute measured ripple value Q the margin which the measured ripple passes or fails the user defined maximum ripple value Starting and Stopping the Ripple Test Once the list of ripple limits has been set up start the ripple test by pressing RIPL TEST on OFF fromthe Ripple Test Menu until ON is displayed on the softkey Pressing this softkey toggles the analyzer between ripple test on and ripple test off status Figure 1 65 shows the filter pass band with the scale changed to 1 dB division being ripple tested Note that the filter fails the ripple test The portions of the pass band trace which do not meet the test requirements are dis
237. e Devices 8 Modify the calibration kit thru definition by entering in the electrical delay of adapter A3 Savethis as a user kit For example if A3 has 100 ps of delay press CAL KIT MODIFY DEFINE STANDARD MODIFY STD DEFINITION SPECIFY OFFSET OFFSET DELAY STD DONE DEFINED RETURN KIT DONE MODIFIED SAVE USER KIT 9 Perform the desired calibration with this new user kit 10 Connect the test device as shown in Figure 6 17 and measure the device 6 48 Calibrating for Increased Measurement Accuracy Minimizing Error When Using Adapters Minimizing Error When Using Adapters To minimize the error introduced when you add an adapter to a measurement system the adapter needs to have low SWR or mismatch low loss and high repeatability Figure 6 20 Adapter Considerations Leakage signals Reflected signal AA Coupler has 40dB Directivity Worst NU Adapter orst ELT est TM Cane H E DUT System P total P nak P 7mm SMA Male Directivity a S 7 mm to SMA f me lp SWR 1 06 17 dB UE 7 mm to N f N m to SMA f SWR 1 05 SWR 1 25 7 mm to N m N f to SMA m SMA f to f 14 dB SWR 1 05 SWR 1 25 SWR 1 15 pg6237 In areflection measurement the directivity of a system is a measure of the error introduced by an imperfect signal separation device It typically includes any signal that is detected at the coupled port which has not been reflected by the test device This directivi
238. e ECal calibration to accurately measure noninsertable devices The following adapters shown in Figure 6 26 are needed Adapter A1 which mates with port 1 of the DUT must be installed on Port 1 of the analyzer Adapter A2 which mates with port 2 of the DUT must be installed on Port 2 of the analyzer Adapter A3 must match the connectors on the DUT The effects of this adapter will be completely removed with this calibration technique NOTE Adapters A1 and A2 become part of the test setup to allow connection to the DUT Adapter A3 is used during the calibration only Its effects will be removed 6 71 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Figure 6 26 Adapters Needed NETWORK ANALYZER Reference Reference Port 1 Port 2 pa595e The following requirements must also be met An ECal module for performing a 2 port error correction for each connector type must be available Specified electrical length of adapter A3 within 1 4 wavelength for the measurement frequency range For each port a separate 2 port error correction needs to be performed to create two calibration sets The adapter removal algorithm uses the resultant data from the two calibration sets and the nominal electrical length of the adapter to compute the adapter s actual S parameters This data is then used to generate a separate third calibration set in which the forward and reverse match and tracking terms ar
239. e Swept RF IF Conversion Loss High Dynamic Range Swept RF IF Conversion Loss The frequency offset mode enables the testing of high dynamic range frequency converters mixers by tuning the analyzer s high dynamic range receiver above or below its source by a fixed offset This capability allows the complete measurement of both pass and reject band mixer characteristics The analyzer has a 35 dB dynamic range limitation on measurements made directly with its R phaselock channel For this reason the measurement of high dynamic range mixing devices such as mixers with built in amplification and filtering with greater than 35 dB dynamic range must be made on either the analyzer s A or B channel with a reference mixer providing input to the analyzer s R channel for phaselock This example describes the swept IF conversion loss measurement of a mixer and filter The output filtering demonstrates the analyzer s ability to make high dynamic range measurements Set Measurement Parameters for the IF Range Set the following analyzer parameters 100 NUMBER of POINTS Perform a Power Meter Calibration Over the IF Range 1 Calibrate and zero the power meter 2 Connect the measurement equipment as shown in Figure 2 16 CAUTION To prevent connector damage use an adapter part number 1250 1462 as a connector saver for R CHANNEL IN Making Mixer Measurements High Dynamic Range Swept RF IF Conversion Loss Figure 2 16 Connections for Po
240. e arbitrary confusion can be minimized by using consistency H owever standard 5 is always a sliding load SPECIFY CLASS leads to the specify dass menu After the standards are modified use this key to specify a class to group certain standards LABEL CLASS leads tothe label dass menu to give the class a meaningful label for future reference 7 57 Operating Concepts Modifying Calibration Kits LABEL KIT leads toa menu for constructing a label for the user modified cal kit If a label is supplied it will appear as one of the five softkey choices in the select cal kit menu The approach is similar to defining a display title except that the kit label is limited to ten characters TRL LRM OPTION brings up the TRL Option menu KIT DONE MODIFIED terminates the calibration kit modification process after all standards are defined and all classes are specified Be sure to save the kit with the SAVE USER KIT softkey if it is to be used later Define Standard Menus Standard definition is the process of mathematically modeling the electrical characteristics delay attenuation and impedance of each calibration standard These electrical characteristics coefficients can be mathematically derived from the physical dimensions and material of each calibration standard or from its actual measured response The parameters of the standards can be listed in Table 7 1 Table 7 1 Standard Definitions
241. e as if port 1 and port 2 could be connected This is possible because the actual S parameters of the adapter are measured with great accuracy thus allowing the effects of the adapter to be completely removed when the third calibration set is generated 6 72 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Perform the 2 Port Error Corrections 1 Connect adapter A3 to adapter A2 on port 2 as shown in Figure 6 27 Figure 6 27 Two Port Cal Set 1 NETWORK ANALYZER Parallel Port Connection PC Interface Unit ECal Module Reference Port 1 Reference Port 2 PC Interface Power Supply to AC Power pl508ets 2 Connect the ECal module between adapter A1 and adapter A3 3 Press ECal MENU MODULE Ab 4 Press FULL 2 PORT to perform the first 2 port error correction using the E Cal module NOTE When using adapter removal calibration you must save calibration sets to the internal disk not to internal memory 5 Save the results to disk Name the file PORT 1 6 Removethe ECal module and adapter A3 from the setup Connect adapter A3 to adapter A1 on port 1 as shown in Figure 6 28 6 73 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Figure 6 28 Two Port Cal Set 2 NETWORK ANALYZER Parallel Port Connection PC Interface Unit ECal Module A2 Reference Port 1 PC Interface Power Supply Re
242. e bxc a RERERPRE RPPRQIIRPEEXQUEPEQCGqG EQ 1 102 Naming Files Generated by a Sequence 0 cee 1 102 Storing a SEQUENCE oh a DISK uia de ppxbexa4 Ped Rd Xx Ge SRR H IK oh RE RS dde 1 103 Loading a Sequence irom DISK 444 3 3b s ASA ERXEEDRPRC ERPRRESUTREPAPERTEREE PRA 1 103 Purginga Sequence ram DISK osea quwadk attt rikiai TARE e Ei cpi cR bad 1 103 Prnt a SegUbEB ucadaxgag d 4 EXIRET KD EERE KERB IGE EERE Rn Fo EORR 1 104 In Depth Sequencing Information sslseseeseeseeee nne 1 104 Using Test Sequencing to Test a Device 1 2 2 eee 1 113 Cascading Multiple Example Sequences 0 0002 cee 1 113 Loop Counter Example Sequence swe dew nd ERRRROROERAOEREEGROG EAR ETCRERR REA ER EA 1 114 Generating Files in a Loop Counter ExampleSequence l llsulslsss 1 115 Limit Test Example SedgUence aci 60505044200 09S0Rs S40 ore PENIS ERE RER da d 1 117 2 Making Mixer Measurements Usma TES E DO BE ees qdaradebdape d wr qiek d d oq OPER E E Pac Ger needa teas ae CAO 2 2 Mixer Measurement Capabilities lille eene 2 3 Measurement CONICS GUNS eiria rire tidia diet c 3d we hee NIS dw HSE ESE we xk 2 4 Minimizing Source and Load Mismatches 0000 e eee eee 2 4 Reducing the Effect of Spurious Responses 0 00 eee 2 5 Eliminating Unwanted Mixing and Leakage Signals 00 cee eee eee 2 6 How RF and IF Are Denied oeaad tsaax AG be ECCE doe EEN EEE CCCo ee 2 7 Frequency Offset Mode Opera
243. e completed the display should read 0 dBm 10 Savethe power meter and receiver calibration to an instrument state by pressing Save Recall SAVE STATE 2 14 Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode Setting the Analyzer to Make an R Channel Measurement 1 Connect the equipment as shown in Figure 2 12 Figure 2 12 R Channel Mixer Measurement Equipment Setup NETWORK ANALYZER 550 MHz Low Pass Filter 3 dB External LO Source pa5186e NOTE An error message will be displayed while the R In port is disconnected Ignorethis error message until step 3 is complete The analyzer is now displaying the conversion loss of the mixer calibrated with power meter accuracy 2 While the analyzer is still set to the IF frequency range set the frequency offset mode LO frequency from the analyzer by pressing INSTRUMENT MODE FREQ OFFS MENU LOMENU FREQUENCY CW Note that this is the example LO frequency Enter the LO frequency for your measurement instead The LO menu is used to set only the LO CW frequency All other settings apply when using the HP Agilent 8625A external source 3 To select the converter type and a high side LO measurement configuration press RETURN DOWN CONVERTER RF lt LO Note that these are the example settings Enter the settings for your measurement instead Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode 4 Turn on frequency offset op
244. e delta reference 1 Press AMODE MENU AREF 1 tomake marker 1 a reference marker 2 To move marker 1 to any point that you want to reference e Turn the front panel knob OR Enter the frequency value relative to the reference marker on the numeric keypad 3 Press MARKER 2 and move marker 2 to any position that you want to measure in reference to marker 1 1 28 Making Measurements Using Markers Figure 1 16 Marker 1 as the Reference Marker Example CHL Soy log MAG 19 dB REF 50 dB 2 2 9117 dB CENTER 134 880 8 MHz SPAN 35 8880 OBB MHz aw000032 4 To change the reference marker to marker 2 press AMODE MENU AREF 2 To Activate a Fixed Marker When a reference marker is fixed it does not rely on a current trace to maintain its fixed position This is convenient when comparing two different measurement conditions To activate a fixed marker on the analyzer press MKR ZERO Marker zero puts a fixed reference at the current position of the active marker To change to a Delta Marker to a fixed reference marker press A MODE MENU AREF AFIXED MKR Using the MKR ZERO Key to Activate a Fixed Reference Marker Marker zero enters the position of the active marker as the A reference position Alternatively you can specify the fixed point with FIXED MKR POSITION Marker zero is canceled by switching delta mode off 1 To place marker 1 at a point that you wou
245. e extra care to selecting the attenuator located at the mixer s IF port to avoid overdriving the receiver For best results you should choose the attenuator value so that the power incident on the analyzer R channel input is less than 10 dBm and greater than 35 dBm Making Mixer Measurements Measurement Considerations Figure 2 2 Conversion Loss versus Output Frequency without Attenuators at Mixer Ports CHI A M log MAG 5 gB REF O aB Sar START 300 000 GOO mhz STOP 1 500 006 OOO MHz pg l 2 c Figure 2 3 Example of Conversion Loss versus Output Frequency with Attenuation at All Mixer Ports CH1 R M log MAG 5 dB8 REF O gB Hig ofs START 500 000 000 MHz STOP 1 800 000 000 MHz pa l l c Reducing the Effect of Spurious Responses By choosing test frequencies frequency list mode you can reduce the effect of spurious responses on measurements by avoiding frequencies that produce IF signal path distortion Making Mixer Measurements Measurement Considerations Eliminating Unwanted Mixing and Leakage Signals By placing filters between the mixer s IF port and the receiver s input port you can eliminate unwanted mixing and leakage signals from entering the analyzer s receiver Filtering is required in both fixed and broadband measurements Therefore when configuring broad band swept measurements you may need to trade some measurement bandwidth for the ability to more select
246. e following steps provide detailed instruction on how to apply various features of the analyzer to accomplish these measurements NOTE In a compression measurement it is necessary to know the RF input or output power at a certain level of gain compression Therefore both gain and absolute power level need to be accurately characterized Uncertainty in a gain compression measurement is typically less than 0 05 dB Also each input channel of the analyzer is calibrated to display absolute power typically within 0 5 dBm up to 3 GHz and 1 dB up to 6 GHz This can be improved by calibrating the power meter Refer to Power Meter Measurement Calibration on page 6 33 for information on calibrating the power meter Figure 1 48 Diagram of Gain Compression a b n qd m PINNA m ex ye e o c UT et i o o o a ot D c5 nput Power dBm Input Power dBm pb697d 1 Set up the stimulus and response parameters for your amplifier under test To reduce the effect of noise on the trace press IF BW 1099 GD Trans FWD S21 B R 2 Perform the desired error correction procedure Refer to Chapter 6 Calibrating for Increased M easurement Accuracy for instructions on how to make a measurement correction 3 Connect the amplifier under test 1 59 Making Measurements Measuring Amplifiers 4 To produ
247. e in degrees RI for real and imaginary pair Rn the reference impedance in ohms for the analyzer making the measurement R 50 or R 75 The format choice is selected by the current selection under the FORMAT menu To select the DB format the FORMAT must be LOG MAG For MA the FORMAT must be LIN MAG unlike CITIfile and all other FORMAT selections will output RI data The S2P data will always represent the format array data including effects of electrical delay and port extensions A CITIfile will be saved at the same time To be consistent with previous versions the CITIfile data saved will represent the DATA array corrected data without effects of electrical delay or port extensions CAUTION Using the smoothing feature or saving data displayed in time domain format may result in invalid S2P data Avoid using these functions when saving S2P files 4 41 Printing Plotting and Saving Measurement Results Saving Measurement Results Here is an S2P example filefor an 11 point measurement of a 20 dB HZ S DB R 50 Network Analyzer HP8753E 0611 50000000 250000000 450000000 650000000 850000000 1050000000 1250000000 1450000000 1650000000 1850000000 2050000000 4 42 56 74 53 015 52 094 51 758 50 95 50 235 49 883 48 477 48 462 47 503 46 938 15 178 20 219 1 7331 20 373 5 8173 20 391 8 02 20 189 11 472 20 163 9 3562 20 178 9 2574 20 442 5 9944 20 201 3 5156 20 161 1840 2
248. e softkey for the desired sequence NOTE If the sequence is on a disk load the sequence as described in a previous procedure and then follow the printing sequence In Depth Sequencing I nformation Features That Operate Differently When E xecuted in a Sequence The analyzer does not allow you to use the following keys in a sequence lt 3 and X keys key and backspace key vidue That Sequencing Completes Before the Next Sequence Command egins Theanalyzer completes all operations related to thefollowing commands before conti nuing with another sequence command Single sweep e number of groups auto scale marker search e marker function data 2 memory recall or save internal or external copy list values and operating parameters CHANT CHAN2 Wait O Wait O is the special sequencing function WAIT x with a zero entered for the delay value 1 104 Making Measurements Using Test Sequencing Commands That Require a Clean Sweep Many front panel commands disrupt the sweep in progress for example changing the channel or measurement type When the analyzer does execute a disruptive command in a sequence some instrument functions are inhibited until a complete sweep is taken This applies to the following functions autoscale data memory Forward Stepping in Edit Mode In the sequence modify mode you can step through the selected sequence list wherethe analyzer executes each step us
249. e test set Option 014 No Yes Yes Segmented error correction in frequency list mode Yes Yes Yes Swept list frequency sweep No Yes Yes Sweep speed 201 points one port cal ms 200 77 70 Sweep speed 201 points full 2 port cal 510 145 121 Speed in time domain transform 350 46 42 Data I O speed GPIB ms internal binary 35 11 16 Four parameter display No Yes Yes Markers display channel 4 5 5 Total viewable markers at any time 8 20 20 Color display Yes Yes Yes Flat panel LCD No Yes Yes VGA output No Yes Yes Delete display Option 1DT No Yes No Test sequencing Yes Yes Yes Automatic sweep time Yes Yes Yes External source capability Yes Yes Yes Tuned receiver mode Yes Yes Yes Printer plotter buffer Yes Yes Yes Harmonic measurements Option 002 Yes Yes Yes Frequency offset mode mixer measurements Yes Yes Yes dc bias to test device Yes Yes Yes 7 90 Table 7 6 Comparing the 8753D E ES Continued Operating Concepts Differences between 8753 Network Analyzers Feature 8753D 8753E 8753ES nterfaces RS 232 parallel and DIN keyboard Yes Yes Yes User defined preset Yes Yes Yes Non volatile memory in Kbytes 512 2000 2000 Dynamic range 30 kHz 3 GHz 110 dB 110 dB8 110 dB8 Dynamic range 3 GHz 6 GHz 105 dB 105 dB 105 dB Real time dock Yes Yes Yes a 90 dB from 30 kHz to 50 kHz 100 dB from 300 kHz to 16 MHz Table 7 7 Comparing the 8753D E E S Option 011 Network Analyzers
250. e the T pointer to the A character 5 Press SELECT LETTER DONE 6 Define the next measurement plot that you will be saving to disk For example you may want only the data trace to appear on the second plot for measurement comparison n this case you would press DEFINE PLOT and choose PLOT DATAON PLOT MEM OFF PLOT GRAT OFF PLOT TEXT OFF PLOT MKR OFF Press PLOT The analyzer will assign PLOTOOFP because you renamed the last file saved Press and turn the front panel knob to highlight the name of the file that you just saved Press FILE UTILITIES RENAME FILE and turn the front panel knob to place the T pointer to the B character 10 Press SELECT LETTER DONE 11 Continue defining plots and renaming the saved file until you have saved all the data that you want to put on the same page Renaming the files as shown allows you to use the provided program that organizes and plots the files according tothe file naming convention Plot File Recognized Filename First File Saved PLOTOOFPA Second File Saved PLOTOOFPB Third File Saved PLOTOOFPC Fourth File Saved PLOTOOFPD 4 27 Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page from Disk Figure 4 10 shows plots for both the frequency and time domain responses of the same device Figure 4 10 Plotting Two Files on the Same Page CH1 S11 log MAG 10 dB REF 40 dB
251. ePes 4d b RARROGROAC AP A 6 4 tng Faolatrom C all bl SU BEL ossa acp dee dC Qe PERCY d o DORE ONES Fe e s de deb 6 4 saving talibraber Date casvetesibieveiee E IATERERGHEET eR T A REPEENA Tp E 6 5 Restarting 3 CIBC OL DE saa bode ee gered sq Pees Ride Ow rri eqq iode pa 6 5 The Calibradon Standards 24064 pa OU EACH EROCIECROR REDS REE DEES we Oe 6 5 Frequency Response of Calibration Standards 0 0 eee eens 6 6 Initerpolated Error Correction asciicetar taki estaxqsteseesbed AK ee ERI RN RE bo ees 6 8 Erro Correction Stimulus State 4c deck d dO RC COR CR HE OO ER ORO ER Ced 6 9 Procedures for Error Correcting Your Measurements 0 0 cece eee nee ene eee 6 10 TPSO ECFOP SOS thers hard e HE Y XR e DOR Res EXER b Noe PRAM lai 6 10 Frequency Response Error Corrections isxssssnesxkkkexker ER kEFerkEecrkbexxds 6 12 Response Error Correction for Reflection Measurements 000 cece eee eens 6 12 Response Error Correction for Transmission Measurements 0000 cence ees 6 14 Recover CalDration 4133 0 944 dee EXC ROGO ERE e XR E de Pedo e Y de b 6 15 Frequency Response and Isolation Error CorrectionS eee eee eens 6 17 Response and Isolation Error Correction for Transmission Measurements 6 17 Response and Isolation Error Correction for Reflection Measurements 6 19 Enhanced Frequency Response Error Correction 0000 e eects 6 22 Enhanced Reflection Calibration ise x vei eee eR ec ie XC
252. ear in the brackets under SEL QUAD Figure 4 8 Plot Quadrants STOP 3 000 000 MH 4 f i i ko hw EE d CHI CENTER 1 SPAN 2 ps H SPAN 2 ps pg65e 4 Press PLOT 5 Makethe next measurement that you want to see on your hardcopy 6 Press and choose another quadrant where you want to place the displayed measurement 7 Repeat the previous three steps until you have captured the results of up to four measurements 4 18 Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page Using a Pen Plotter If You Are Plotting to an HPGL Compatible Printer 1 Configure and define the plot as explained in Configuring a Plot Function on page 4 9 and Defining a Plot Function on page 4 13 2 Press PLOT PLOTTER FORM FEED toprint the data the printer has received NOTE Use test sequencing to automatically plot all four S parameters 1 Set all measurement parameters 2 Perform a full 2 port calibration 3 Enter the test sequence NEW SEQ MODIFY SEQ SEQUENCE 1SEQ1 Refl FWD S11 A R SEL QUAD SELECT DISK LEFT UPPER PLOT Trans FWD S21 B R SEL QUAD LEFT LOWER PLOT Refl REV S22 B R SEL QUAD RIGHT UPPER PLOT Trans REV S
253. easurement data for the active channel 1 To view a data trace that you have already stored to the active channel memory press MEMORY This is the only memory display mode where you can change the smoothing and gating of the memory trace 2 To view both the memory trace and the current measurement data trace press DATA and MEMORY To Divide Measurement Data by the Memory Trace You can usethis feature for ratio comparison of two traces for example measurements of gain or attenuation 1 You must have already stored a data tracetothe active channel memory as described in To Save a Data Traceto the Display Memory on page 1 19 2 Press DATA MEM todividethe data by the memory The analyzer normalizes the data to the memory and shows the results To Subtract the Memory Trace from the Measurement Data Trace You can usethis feature for storing a measured vector error for example directivity Then you can later subtract it from the device measurement 1 You must have already stored a data tracetothe active channel memory as described in To Save a Data Traceto the Display M emory on page 1 19 2 Press DATA MEM to subtract the memory from the measurement data Theanalyzer performs a vector subtraction on the complex data To Ratio Measurements in Channel 1 and 2 You may want to usethis feature when making amplifier measurements to produce a trace that represents gain compression For example with the channels uncoup
254. easurement data points to 101 press NUMBER OF POINTS CZ To select the transmission measurement press Trans FWD S21 B R To view the data trace press Scale Ref AUTOSCALE Step 3 Perform and apply the appropriate error correction Refer tothe Chapter 5 Optimizing Measurement Results for procedures on correcting measurement errors To save the instrument state and error correction in the analyzer internal memory press Save Recall SELECT DISK INTERNAL MEMORY RETURN SAVE STATE Step 4 Measure the device under test Replace any standard used for error correction with the device under test To measure the insertion loss of the bandpass filter press Marker Search SEARCH MAX 1 5 Making Measurements Making a Basic Measurement Step 5 Output the measurement results To create a printed copy of the measurement results press PRINT MONOCHROME or PLOT Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures on how to set up a printer and define a print plot or save results Making Measurements Measuring Magnitude and Insertion Phase Response Measuring Magnitude and Insertion Phase Response This measurement example shows you how to measure the maximum amplitude of a surface acoustic wave SAW filter and then how to view the measurement data in the phase format which provides information about the phase response Measuring the Magnitude Response 1 Connec
255. ecibels dB LIN MAG linear magnitude is a format that displays the response as reflection coefficient p This can be thought of as an average reflection coefficient of the discontinuity over the frequency range of the measurement Usethe REAL format only in low pass mode 3 13 Making Time Domain Measurements Time Domain Bandpass Mode Table 3 1 Time Domain Reflection Formats Format Parameter LIN MAG Reflection Coefficient unitless O p 1 REAL Reflection Coefficient unitless 1 lt p lt 1 LOG MAG Return Loss dB SWR Standing Wave Ratio unitless Transmission Measurements Using Bandpass Mode The bandpass mode can also transform transmission measurements to the time domain For example this mode can provide information about a surface acoustic wave SAW filter that is not apparent in the frequency domain Figure 3 11 illustrates a time domain bandpass measurement of a 321 MHz SAW filter Figure 3 11 Transmission Measurement in Time Domain Bandpass Mode CH1 S21 log MAG 10 db REF 40 dB 2 11 821 dB CH S21 log MAG 10 db REF 40 dB 4 61 721 dB hp 65516 ns hp 1 973 ps Cor Cor MARKER 4 149132 s 57356 m 3 jp Er Lue CH1 CENTER 1 ps SPAN 2 ps CH1 CENTER 1 ps SPAN 2 ps 655 6 ns gt A m E D an Interpreting the Bandpass Transmiss
256. ecti ng Cables Cables that connect the device under test DUT to the analyzer are often the most significant contribution to random errors of your measurement You should frequently perform the following steps as a precaution against errors caused by cable interconnections nspect for lossy cables nspect for damaged cable connectors Practice good connector care techniques Minimize cable position changes between error correction and measurements nspect for cables which dramatically change magnitude or phase response when flexed This may indicate an intermittent problem Improper Calibration Techniques Calibrations techniques performed improperly contribute to random errors to your measurement You should frequently perform the following steps as a precaution against errors caused by calibration techniques Verify the correct calibration kit definition is selected Verify the correct standards have been connected Sweeping Too Fast for Electrically Long Devices It is possible to sweep too fast for electrically long devices This will result in measurement error Refer to Making Accurate Measurements of Electrically Long Devices on page 5 7 Connector Repeatability Connector repeatability is a source of random measurement error Measurement error corrections do not compensate for these errors For all connectors you should frequently perform the following steps as a precaution against errors caused by conn
257. ection NETWORK ANALYZER Open Short Load Open Short Load For S44 For Soo pa585e 8 To measure the standard when the displayed trace has settled press OPEN NOTE If the calibration kit that you selected has a choice between male or female calibration standards remember to select the sex that applies tothe test port and not the standard The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the OPEN softkey after it measures the calibration standard 9 Disconnect the open and connect a short circuit to the test port 10 To measure the standard when the displayed trace has settled press SHORT The analyzer measures the short circuit and underlines the SHORT softkey 11 Disconnect the short and connect an impedance matched load to the test port 12 When the displayed trace has settled press LOADS select the type of load you are using and then press DONE LOADS when the analyzer has finished measuring the load Noticethat the LOADS softkey is now underlined 6 27 Calibrating for Increased Measurement Accuracy One Port Reflection Error Correction 13 To compute the error coefficients press DONE 1 PORT CAL Theanalyzer displays the corrected data trace The analyzer also shows the notation Cor tothe left of the screen indicating that the correction is switched on for this channel NOTE The open short and load could be measured in any order and nee
258. ector repeatability nspect the connectors Clean the connectors Gaugethe connectors Usecorrect connection techniques Refer to Taking Care of Microwave Connectors on page 5 3 5 4 Optimizing Measurement R esults Increasing Measurement Accuracy Temperature Drift Electrical characteristics will change with temperature due to the thermal expansion characteristics of devices within the analyzer calibration devices test devices cables and adapters Therefore the operating temperature is a critical factor in their performance During a measurement calibration the temperature of the calibration devices must be stable and within 25 5 C Useatemperature controlled environment Ensurethetemperature stability of the calibration devices Avoid handling the calibration devices unnecessarily during calibration e Ensurethe ambient temperature is 1 C of measurement error correction temperature Frequency Drift Minute changes in frequency accuracy and stability can occur as a result of temperature and aging on the order of parts per million If you require greater frequency accuracy override the internal crystal with a high stability external source frequency standard or if your analyzer is equipped with Option 1D5 usethe internal frequency standard Performance Verification You should periodically check the accuracy of the analyzer measurements by performing a measurement verification at least once
259. ed as filename DATAOO d1 Thefile extension d1 indicates that the data from the analyzer s channel 1 is error corrected data only if the analyzer s error correction featureis enabled in other words you have performed a calibration Otherwise the data is the same as data stored in the analyzer s raw data arrays Data stored in the data arrays does not have any formatting applied to it Format Arrays Press Save Recall DEFINE DISK SAVE FORMAT ARY ON Data created the first time in this manner will be saved as filename FILEOO f1 The file extension f1 indicates the data is formatted per Figure 4 13 using the analyzer s channel 1 Depending on what features you ve selected data in the format arrays includes data in the data arrays plus one or more of the following features Trace math i e data memory Gating Option 010 Electrical delay Conversion for complex impedance Z admittance Y etc Transform Option 010 Format log lin phase delay SWR exduding Smith and Polar e Smoothing In each of these examples most users will select SAVE USING ASCII under the DEFINE DISK SAVE softkey menu If GRAPHICS on OFF is turned ON an additional file will be created with file extension gO This is a Hewlett Packard Graphics Language HPGL file 4 50 Printing Plotting and Saving Measurement Results Re Saving an Instrument State Re Saving an Instrument State f you re save a file the analyzer overwr
260. edifficult to make repeatable on wafer contacts due to the size of the device contact pads The capability of making non coaxial measurements is available with TRL thru reflect line or LRM line reflect match calibration For in depth information on TRL LRM calibration refer to Calibrating for Non Coaxial Devices on page 6 52 Duetothe simplicity of the calibration standards TRL or LRM calibrations may be used for non coaxial applications such as on wafer measurements This type of calibration with time domain gating and a variety of probe styles can provide optimal accuracy in on wafer measurements At frequencies where on wafer calibration standards are available short open load thru SOLT calibrations can also be done and may be preferred due to the better accuracy of the SOLT calibration method Fixtures Fixtures are needed to interface non coaxial devices to coaxial test instruments It may also be necessary to transform the characteristic impedance from standard 50 Q instruments to a non standard impedance and to apply bias if an active device is being measured For accurate measurements the fixture must introduce minimum change to the test signal not destroy the test device and provide a repeatable connection to the device For information about test fixtures for your measurement systems ask for literature number 5962 9723E or contact nter Continental Microwave 1515 Wyatt Drive Santa Clara CA 95054 USA Web site
261. eePERRAGU REC REXQEQE REO ORERIERqu DEERE qd pads 7 78 Sudgpess NBI eee eee ee eS ee eee ee doe ERE EEG d e Perder Eck ARA 7 79 WS ie Parallel POE dan eee deiecta asset duet tesa OILERS sas CERT SISA x PP Ee 7 79 Lint Line OBErat lola sees Ed eER IS ER ERR HR ERE RIF PESP QUERI abate thi ee E 7 81 EGIELITIES MOI cease ca EEIRICe PRIEST O SSE RES ee 249 E IESUS P Se OEE 7 82 Ed Segment MENU cuseaxsctetx EPePb i iakin uii ORE Rp oe Pabace Pap ap dedos 7 82 Css EMS MONU ugue addo ded e XR DECR e Crue LOSERS ES AEE EOE debe 7 82 Knowing Ehe Instrument Modes i Ligas ER CR ERT RRERSFETERGRIC P HERE E RE E be ERE 7 83 Network Analvzer MOJE eii osqepeptbebTOqeRPARERTPCOTePTIQITUPPPQRPGGE d eR Pqq peas 7 83 External Source MOD cecruiocerbmsrud 4b da RERE E hA Ru ER dees ERR ROG EROR 7 83 Tuned Becever MOS ui ead oe bee oh RYE eR REE her bReSy Ss a S4 Kasse oon dis 7 85 Freguenc Ol sel Operation ois4ic2 es ceeb ii bei eX Ed sca bedeeebiad ee sadbiosees 7 87 Harmonie Operation Option 002 ONIY ixawoxaka kA WTARXCPEERQE P eannes eae E uen 7 87 Differences between 8753 Network Analyzers 0 000 c eee 7 89 8 Safety and Regulatory Information General Enter iatOre sia by xa ERA ee PEN HN wo DER d drfore POR ae INS PEER RISC wea ERRORS 8 2 MantenNa oed dtd CEP RREATASIHD VERAT AP breed did EqERERATEPEEDEPJIHS Fa d 8 2 Bis E VLonld RRCPRPRERRPRIYEQTPPPEPRPERBQVPRPEREEGCqQRPPERRISORQRPCREIF PRORLRPEdpa 8 2 Shipment TOf SEVIS Ludbxackiwia seed KRG CA E
262. efault Values Plotting Parameter Default Value Plotting Parameter Default Value Select Quadrant Full page Plot Scale Full Auto Feed ON Plot Speed Fast Define Plot All plot elements on Line Type 7 solid line Data M emory Graticule Text Marker Pen Numbers Channel 1 and 3 2 5 1 7 7 Pen Numbers Channel 2 and 4 Data M emory Graticule Text Marker 3 6 1 7 7 4 16 Printing Plotting and Saving Measurement Results Plotting One Measurement Per Page Using a Pen Plotter Plotting One Measurement Per Page Using a Pen Plotter 1 Configure and define the plot as explained in Configuring a Plot Function on page 4 9 and Defining a Plot Function on page 4 13 2 Press Copy PLOT 1 If you defined the AUTO FEED OFF press PLOTTER FORM FEED after the message COPY OUTPUT COMPLETED appears Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page Using a Pen Plotter Plotting Multiple Measurements Per Page Using a Pen Plotter 1 Configure and definethe plot as explained in Configuring a Plot Function on page 4 9 and Defining a Plot Function on page 4 13 2 Press Copy SEL QUAD 3 Choose the quadrant where you want your displayed measurement to appear on the hardcopy The following quadrants are available L LEFT UPPER 1 LEFT LOWER I RIGHT UPPER 1 RIGHT LOWER The selected quadrant will app
263. eference plane 5 6 Optimizing Measurement R esults Making Accurate Measurements of Electrically Long Devices Making Accurate Measurements of Electrically Long Devices A device with a long electrical delay such as a long length of cable a SAW filter or normal devices measured over wide sweeps with very fast rates presents some unusual measurement problems to a network analyzer operating in swept frequency mode Often the measured response is dependent on the analyzer s sweep ti me and incorrect data may be obtained At faster sweep rates the magnitude of the response may seem to drop and look distorted while at slower sweep rates it looks correct The results may indicate that a cable has more loss than it truly does or that a filter has some unusual ripple in the passband which is not really there This section describes the cause of this behavior and how to accurately measure these electrically long devices The Cause of Measurement Problems When using a vector network analyzer to measure a device that has a long electrical delay AT the device s time delay causes a frequency shift between its input and output signals The frequency shift AF equals the product of the sweep rate and the time delay AF dF dt x AT Since frequency is changing with time as the analyzer sweeps the time delay of the DUT causes a frequency offset between its input and output In the analyzer receiver the test and reference input signals
264. effectively have two separate sources U ncoupling the test ports allows you to have different power levels on each port Channel coupling CH PWR COUPLED toggles between coupled and uncoupled channel power With the channel power coupled the power levels are the same on each channel With the channel power uncoupled you can set different power levels for each channel For the channel power to be uncoupled the other channel stimulus functions must also be uncoupled COUPLED CH OFF Test port coupling PORT PWR COUPLED toggles between coupled and uncoupled test ports With the test ports coupled the power level is the same at each port With the ports uncoupled you can set a different power level at each port This can be useful for example if you want to simultaneously perform a gain and reverse isolation measurement on a high gain amplifier using the dual channel mode to display the results In this case you would want the power in the forward direction S21 much lower than the power in the reverse direction S15 7 10 Operating Concepts Sweep Time Sweep Time The SWEEP TIME softkey selects sweep time as the active entry and shows whether the automatic or manual mode is active The following explains the difference between automatic and manual sweep ti me Manual sweep time As long as the selected sweep speed is within the capability of the instrument it will remain fixed regardless of changes to other mea
265. egins 1 104 commands that require a clean sweep 1 105 decision making functions 1 111 embedding loop counter valuein title 1 105 features that operate differently in a sequence 1 104 forward stepping in edit mode 1 105 gosub sequence command 1 106 GPIO mode 1 106 limit test decision making 1 111 loop counter decision making 1 112 sequence decision making menu 1 111 sequence size 1 105 sequence that jumps to itself 1 111 sequencing special functions menu 1 111 titles 1 105 TTL I O menu 1 107 TTL input decision making 1 107 1 111 TTL out menu 1 111 TTL output for controlling peripherals 1 107 indicators GPIB STATUS 7 78 initializing loop counter value to 26 2 27 input ports menu 7 23 input power 1 58 inserting a command 1 100 insertion phase response 1 7 1 8 instrument markings 8 4 instrument modes 7 83 external source mode 7 83 frequency offset operation 7 87 harmonic operation 7 87 network analyzer mode 7 83 tuned receiver mode 7 85 instrument state file deleting 4 51 files 4 46 resaving 4 51 saving 4 36 7 65 saving and recalling 4 34 interconnecting cables 5 4 internal memory 4 34 interpolated error correction 6 8 interpolation in power meter calibration 6 34 interpreting bandpass reflection response horizontal axis 3 13 bandpass reflection response vertical axis 3 13 bandpass transmission response horizontal axis 3 14 bandpass transmission response vertical axi
266. elect the preset values of 201 points and a 300 kHz to 3 GHz frequency range Now press SET FREQ LOWPASS and observe the change in frequency values The stop frequency changes to 2 999 GHz and the start frequency changes to 14 925 MHz This would cause a distortion of measurement results for frequencies from 300 kHz to 14 925 MHz NOTE If the start and stop frequencies do not conform to the low pass requirement before a low pass mode step or impulse is selected and transform is turned on the analyzer resets the start and stop frequencies If error correction is on when the frequency range is changed this turns it off Therefore set the frequency range for time domain low pass before performing a calibration Making Time Domain Measurements Time Domain Low Pass Mode Table 3 2 Minimum Frequency Ranges for Time Domain Low Pass Number of Points Minimum Frequency Range Number of Points Minimum Frequency Range 3 30 kHz to 0 09 MHz 201 30 kHz to 6 03 MHz 11 30 kHz to 0 33 MHz 401 30 kHz to 12 03 MHz 26 30 kHz to 0 78 MHz 801 30 kHz to 24 03 MHz 51 30 kHz to 1 53 MHz 1601 30 kHz to 48 03 MHz 101 30 kHz to 3 03 MHz Minimum Allowable Stop Frequencies The lowest analyzer measurement frequency is 300 kHz 30 kHz with Option 006 therefore for each valueof n thereis a minimum allowable stop frequency that can be used That is the minimum stop frequency n x 30 kHz Table 3 2 lists the minimum frequency
267. eled with the desired sequence number Stopping a Sequence To stop a sequence before it has finished press Local Editing a Sequence Deleting Commands 1 To enter the creati on editing mode press NEW SEQ MODIFY SEQ 2 Toselect the particular test sequence you wish to modify sequence 1 in this example press SEQUENCE 1SEQ1 1 99 Making Measurements Using Test Sequencing 3 To move the cursor to the command that you wish to delete press CZ or Cx f you wish to scroll through the sequence without executing each line as you do so you can press the lt key and scroll through the command list backwards f you use the key to move the cursor through the list of commands the commands are actually performed when the cursor points to them This feature allows the sequence to be tested one command at a time 4 To delete the selected command press 5 backspace key Press DONE SEQ MODIFY to exit the modify edit mode Inserting a Command 1 5 To enter the creation editing mode press NEW SEQ MODIFY SEQ To select the particular test sequence you wish to modify sequence 1 in this example press SEQUENCE 1SEQ1 Toinsert a command move the cursor tothe lineimmediately above the line where you want to insert a new command by pressing CS or 7 f you use the C key to move the cursor through the list of commands the commands are actually performed when the curso
268. em from the analyzer to another analyzer or possibly to an external computer controller so the sequence can be sent to another analyzer How to Use Test Sequencing The following procedures which are based on an actual measurement example show you how to do the following create a sequence title a sequence edit a sequence clear a sequence change a sequence title namefiles generated by a sequence Store a sequence load a sequence purge a sequence print a sequence Creating a Sequence 1 To enter the sequence creation mode press NEW SEQ MODIFY SEQ As shown in Figure 1 75 a list of instructions appear on the analyzer display to help you create or edit a sequence 1 97 Making Measurements Using Test Sequencing Figure 1 75 Test Sequencing Help Instructions TEST SEQUENC MODIFY To INSERT To DELETE To STEP To END RUN To START KEYS To STOP E To PAUSE Only sequenc Select a sof ING Any function inserted after cursor BACK SP deletes line at cursor Use ARROW keys or knob ARROW up does the function after the cursor and moves list up ARROW down only moves list down Press DONE SEQ MODIFY in SEQUENCE MENU Press DO SEQUENCE in SEQUENCE MENU All front panel keys except LOCAL are locked out until sequence stops Press LOCAL to stop a running sequence Press CONTINUE SEQUENCE in SEQUENCE MENU to restart a paused sequence e 6 is saved when
269. emale calibration standards remember to select the sex that applies tothe test port and not the standard The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the softkey that you selected after it finishes the measurement and computes the error coefficients NOTE This calibration allows only one standard to be measured If you press the wrong key for a standard press RESPONSE again and choose the correct standard Do not use a thru standard for a reflection response correction NOTE You can save or store the measurement correction to use for later measurements that use the same measurement parameters Refer tothe Chapter 4 Printing Plotting and Saving M easurement Results for procedures This completes the response correction for reflection measurements You can connect and measure your device under test 6 13 Calibrating for Increased Measurement Accuracy Frequency Response Error Corrections Response Error Correction for Transmission Measurements 1 Press Preset 2 Select the type of measurement you want to make 1 If you want to make a transmission measurement in the forward direction S21 press Trans FWD S21 B R 1 If you want to make a transmission measurement in the reverse direction 515 press Trans REV S12 A R 3 Set any other measurement parameters that you want for the device measurement power number of points IF ba
270. en the two power ranges the analyzer automatically engages the test set hold mode after measuring both channels once The active channel continues to be updated each sweep whilethe inactive channel is placed in the hold mode The status annotation tsH appears on the left side of the display If averaging is on the test set hold mode does not engage until the specified number of sweeps is completed The MEASURE RESTART and NUMBER OF GROUPS softkeys can override this protection feature Allowing Repetitive Switching of the Attenuator The MEASURE RESTART and NUMBER OF GROUPS softkeys allow measurements which demand repetitive switching of the step attenuator Use these softkeys with caution repetitive switching can cause premature wearing of the attenuator MEASURE RESTART causes one measurement to occur before activating the test set hold mode NUMBER OF GROUPS causes a specified number of measurements to occur before activating the test set hold mode 7 13 Operating Concepts Channel Stimulus Coupling Channel Stimulus Coupling COUPLED CH on OFF toggles the channel coupling of stimulus values With COUPLED CH ON the preset condition both channels havethe same stimulus values Theinactive channel takes on the stimulus values of the active channel In the stimulus coupled mode the following parameters are coupled frequency e number of points Source power e number of groups F bandwidth sweep time e t
271. ent Results Saving Measurement Results Saving in Graphical J PEG Form Graphical measurement results can be saved in J PEG format and used as an illustration in a text editor or desktop publishing application Up to eight traces may be saved in the J PEG file This is done by storing a measurement using DATA MEMORY and turning on DATA AND MEMORY for each of the four channels 1 Press SAVE FILE FORMATS 2 Makesurethat GRAPH FMT J PG is displayed 3 Makesurethat FILETYPE GRAPHIC isunderlined If it is not underlined press the softkey so that GRAPHIC is underlined 4 Insert a 3 5 inch floppy disk in the network analyzer s disk drive 5 Press SAVE FILE to save the display as a graphic in the PEG format The graphic file may be retrieved from the floppy disk on personal computer and can be imported into an application that accepts graphics in the PEG format NOTE When saving measurement results graphically make sure that no onscreen measurement data is displayed as white Since media color is often white any measurement data printed using white will not be visible You may change the analyzer to the factory default color settings by pressing DEFINE PRINT DEFAULT PRNT SETUP to correct this problem However to maintain your current color settings except white check the measurement color settings by pressing DEFINE PRINT PRINT COLORS Press MORE to check the remaining measurement colors To modify any of the measurem
272. ent colors select the measurement and then choose another color from the list of colors that is displayed 1 The network analyzer firmware is based in part on the work of the Independent JPEG Group 4 45 Printing Plotting and Saving Measurement Results Saving Measurement Results Instrument State Files When an instrument state is saved to a floppy disk some or all of the following files may be produced This depends upon which arrays are selected under the DEFINE SAVE STATE softkey menu and whether the selected save format is BINARY or ASCII The XX part of the file name FileXX refers to the number of the instrument state The first instrument state saved to any particular disk will be named File00 and each successive state saved to that disk will be numbered 1 higher than the previous state for example FileO1 and File02 Files with i and p File Extensions The following two files i file and p file are always produced except when DATA ONLY is selected These files were separated to allow backward compatibility with older instruments The binary data contained in these two files is not meant to be read in an external computer FileXX i isa binary file which contains the generic portion of the current instrument state specifically the System Local Preset Copy Save and Sequence settings FileXX p isa binary file which contains portions of theinstrument state specificto later instruments
273. enter the standard numbers for the reverse match thru calibration For default calibration kits this is the thru RESPONSE allows you to enter the standard numbers for a response calibration This calibration corrects for frequency response in either reflection or transmission measurements depending on the parameter being measured when a calibration is performed For default kits the standard is either the open or short for reflection measurements or the thru for transmission measurements 7 63 Operating Concepts Modifying Calibration Kits RESPONSE amp ISOL N allows you to enter the standard numbers for a response amp isolation calibration This calibration corrects for frequency response and directivity in reflection measurements or frequency response and isolation in transmission measurements TRL THRU allows you to enter the standard numbers for a TRL thru calibration e TRL REFLECT allows you to enter the standard numbers for a TRL reflect calibration TRL LINE OR MATCH allows you to enter the standard numbers for a TRL line or match calibration Label Class Menu The label dass menus are used to define meaningful labels for the calibration classes These then become softkey labels during a measurement calibration Labels can be up to ten characters long Label Kit Menu This LABEL KIT softkey within the modify cal kit menu accesses this menu It is identical to the label dass menu and the label standard me
274. ents Conversion Loss Using the Frequency Offset Mode Setting Measurement Parameters for the Power Meter Calibration 1 Connect the measurement equipment as shown in Figure 2 10 Figure 2 10 Connections for Source Calibration NETWORK ANALYZER POWER METER Splitter Power Sensor mixer setup pmcal optO11 2 Fromthe front panel of the analyzer set the desired receiver RF frequency and source output power by pressing INSTRUMENT MODE FREQ OFFS MENU Note that these are the example RF start and stop frequencies Enter the RF start and stop frequencies for your measurement instead If the LO frequency is not set to 0 Hz press LOMENU FREQUENCY CW 0 3 To select the measurement trace press R The measurement trace is shown on the display 4 Select the analyzer as the system controller SYSTEM CONTROLLER Performing a Power Meter Source Calibration Over the RF Range 1 Calibrate and zero the power meter 2 Set the power meter s address SET ADDRESSES ADDRESS P MTR GPIB where aa is the GPIB address of the power meter 2 12 Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode 3 Select the appropriate power meter by pressing POWER MTR until the correct model number is displayed Agilent 436A or Agilent 438A 437 NOTE The Agilent E4418B and E4419B EPM power meters have a 437emulation mode which can be used in this procedure by following these steps f you are using an
275. eparate graticules press Set SPLIT DISP to2X The analyzer shows channel 1 on the upper half of the display and channel 2 on the lower half of the display The analyzer defaults to measuring S44 on channel 1 and S5 on channel 2 1 12 Making Measurements Using Display Functions Figure 1 8 Example Dual Channel with Split Display On CHi Sz tog MAG 19 dB REF 5 dB T CH2 So phase 99 7 REF O0 ey bbb ee a a ee ai START 110 008 288 MHz STOP 166 B ODO MHz aw000027 3 Toreturn to a single graticule display press SPLIT DISPLAY 1X NOTE You can control the stimulus functions of the two channels independent of each other by pressing COUPLED CH OFF Dual Channel Mode with Decoupled Stimulus The stimulus functions of the two channels can be controlled independently using COUPLED CH ON off in the stimulus menu In addition the markers can be controlled independently for each channel using MARKERS UNCOUPLED in the marker mode menu under the key NOTE For dual channel if channels are uncoupled and you have full 2 port calibrations on both channels you will not be able to select a non ratioed measurement For example you can measure S5 or B R but not input B NOTE Auxiliary channels 3 and 4 are permanently coupled by stimulus to primary channels 1 and 2 respectively Decoupling the primary channels stimulus from each oth
276. epresent the ripple limits can be changed by 1 pressing the key 2 pressing MORE ADJUST DISPLAY MODIFY COLORS MORE 3 pressing RIPPLE LIMLINES TINT andturningthe analyzer front panel knob until the desired color appears You may also usethe step keys or the numeric keypad instead of the front panel knob to change the color Checking the Ripple Value Oncetheripple test has been started and is running you may display theripple value of each frequency band in one of two formats the absolute format or the margin format Both formats are described in this section 1 87 Making Measurements Using Ripple Limits to Test a Device To display the ripple value press RIPL VALUE Pressingthis softkey toggles between RIPL VALUE OFF RIPL VALUE ABSOLUTE and RIPL VALUE MARGIN RIPL TEST on OFF fromtheRippleTest Menu until ON is displayed on the softkey Pressing this softkey toggles the analyzer between ripple test on and ripple test off status When the Absolute and Margin choices are selected the frequency band and measurement value are displayed to the right side of the pass fail message described previously This display is displayed in the same color as the pass fail message The frequency band of the displayed value is displayed as Bn where n the frequency band number The frequency band may be changed to display the value of each band To change the displayed frequency band value from the Ripple Test Menu press RIPL VALU
277. equence automatically 1 105 Making Measurements Using Test Sequencing Gosub Sequence Command The GOSUB SEQUENCE softkey located in the Sequencing menu activates a feature that allows the sequence to branch off to another sequence then return to the original sequence For example you could perform an amplifier measurement in the following manner 1 Create sequence 1 for the specific purpose of performing the gain measurement and printing the results This sequence will act as a sub routine 2 Create sequence 2 to set up a series of different input power levels for the amplifier gain measurements n between each power level setting call sequence 1 as a sub routine by pressing GOSUB SEQUENCE SEQUENCE 1 Now sequence 2 will print the measurement results for each input power level applied to the amplifier NOTE The GOSUB SEQUENCE softkey branches the sequence to another sequence in a particular location SEQ1 through SE Q6 not to a given file name The GPIO Mode Theinstrument s parallel port can be used in two different modes By pressing and then toggling the PARALLEL softkey you can select either the COPY mode or the GPIO mode The GPIO mode switches the parallel port into a general purpose input output port In this mode the port can be connected to test fixtures power supplies and other peripheral equipment that the analyzer can interact with through test sequencing TESTSET I O The TESTSET I O in
278. er The calibration kit thru definition is modified to compensate for the adapter and then saved as a user kit However the electrical delay of the adapter must first be found The adapter match will degrade the effective load match terms on both ports as well as degrade the transmission frequency response tracking 1 Refer to Figure 6 19 while performing the steps in this procedure Also refer to page 6 41 for an explanation of A1 A2 and A3 2 Perform a 1 port calibration at Reference Port 1 Refer to Step A of Figure 6 19 Figure 6 19 Determining the Electrical Delay Setup NETWORK ANALYZER NETWORK ANALYZER Reference Reference Reference Port 1 Port 1 Port 2 Step A Step B pl512ets 3 Connect the A3 adapter to Reference Port 1 as shown in Step B of Figure 6 19 Connect a short to the open end of the A3 adapter 4 Measurethe delay of the adapter by pressing DELAY 5 Dividethe resulting delay measurement by 2 to determine the delay of the thru and the short in one direction 6 Determine the offset delay of the calibration short by examining the define standard menu see Define Standard M enus on page 7 58 7 Subtract the offset delay of the short determined in step 6 from the delay of thethru and the short in one direction determined in step 5 Theresult is electrical delay of the thru This valueis used in the next step 6 47 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertabl
279. er 1250 1462 as a connector saver for R CHANNEL IN Figure 2 28 Connections for theFirst Portion of Conversion Compression Measurement NETWORK ANALYZER 700 MHz High Pass Filter 20 dB pa554e 6 To view the absolute input power to the analyzer s R channel press Meas R 7 To store a trace of the receiver power versus the source power into memory and view data memory press DATA gt MEM DATA MEM This removes the loss between the output of the mixer and the input to the receiver and provides a linear power sweep for use in subsequent measurements 8 Make the connections as shown in Figure 2 29 CAUTION To prevent connector damage use an adapter part number 1250 1462 as a connector saver for R CHANNEL IN 2 38 Making Mixer Measurements Conversion Compression Using the Frequency Offset Mode Figure 2 29 Connections for the Second Portion of Conversion Compression Measurement NETWORK ANALYZER 700 MHz High Pass Filter 20 dB Mixer Under Test 3 dB External LO Source pa557e 9 Toset the frequency offset mode L O frequency press INSTRUMENT MODE FREQ OFFS MENU LOMENU FREQUENCY CW 10 To select the converter type press RETURN UP CONVERTER 11 To select a low side LO measurement configuration press RF gt LO FREQ OFFS ON In this low side LO up converter measurement the analyzer source frequency is offset lower than the receiver frequency The analyzer source frequen
280. er does not affect the stimulus coupling between the auxiliary channels and their primary channels Dual Channel Mode with Decoupled Channel Power By decoupling the channel power or port power and using the dual channel mode you can simultaneously view two measurements or two sets of measurements if both auxiliary channels are enabled having different power levels Making Measurements Using Display Functions However there are situations where the analyzer will not update all measurements continuously For analyzers with source attenuators such situations occur if channel 1 requires one attenuation value and channel 2 requires a different value or if 2 port cal is active and the port 1 attenuation valueis not equal tothe attenuation value of port 2 Since one attenuator is used for both measurements this would cause the attenuator to continuously switch power ranges which is not allowed If one of these conditions exist the test set hold mode will engage and the status notation tsH Will appear on the left side of the screen The hold mode leaves the measurement function in only one of the two measurement paths To update both measurements press MEASURE RESTART Refer to Source Attenuator Switch Protection on page 7 13 Viewing Four Measurement Channels Four measurement channels can be viewed simultaneously by enabling auxiliary channels 3 and 4 Although independent of other channels in most variables channels 3 and 4 are per
281. er for one of the following printer interfaces Choose PRNTR PORT GPIB if your printer has an GPIB interface and then configure the print function as follows a Enter the GPIB address of the printer default is 01 followed by x1 b Press and SYSTEM CONTROLLER if there is no external controller connected to the GPIB bus c Press and USE PASS CONTROL if there is an external controller connected to the GPIB bus 4 9 Printing Plotting and Saving Measurement Results Configuring a Plot Function NOTE Choose PARALLEL if your printer has a parallel Centronics interface and then configure the print function as follows Press and then select the parallel port interface function by pressing PARALLEL until the correct function appears L If you choose PARALLEL COPY the parallel port is dedicated for normal copy device use printers or plotters 1 If you choose PARALLEL GPIO the parallel port is dedicated for general purpose I O and cannot be used for printing or plotting Choose SERIAL if your printer has a serial RS 232 interface and then configure the print function as follows a Press PRINTER BAUD RATE and enter the printer s baud rate followed by x1 b To select the transmission control method that is compatible with your printer press XMIT CNTRL transmit control handshaking protocol until the correct method appears LY If you choose Xon Xoff the handshake method allows the printer t
282. er front panel knob use the step keys or the numeric keypad until the desired color appears 1 22 Making Measurements Using Display Functions NOTE Maximum viewing with the LCD display is achieved when primary colors or a combination of them are selected at full brightness 10096 Table 1 2 lists the recommended colors and their corresponding tint numbers Table 1 2 Display Colors with Maximum Viewing Angle Display Color Tint Brightness Color Red 0 100 100 Yellow 17 100 100 Green 33 100 100 Cyan 50 100 100 Blue 67 100 100 M agenta 83 100 100 White N A 100 0 Color is comprised of three parameters Tint The continuum of hues on the color wheel ranging from red through green and blue and back to red Brightness A measure of the brightness of the color Color The degree of whiteness of the color A scale from white to pure color The most frequently occurring color deficiency is the inability to distinguish red yellow and green from one another Confusion between these colors can usually be eliminated by increasing the brightness between the colors To accomplish this press the BRIGHTNESS softkey and turn the analyzer front panel knob If additional adjustment is needed vary the degree of whiteness of the color To accomplish this press the COLOR softkey and turn the analyzer front panel knob NOTE Color changes and adjustments remain in effect until changed again in t
283. er s output needed to lower the output power intothe analyzer The following steps demonstrate the features that best accomplish these measurements 1 Press Sweep Setup COUPLED CH ON Coupling the channels allows you to have the same frequency range and calibration applied to channel 1 and channel 2 2 Press PORT POWER UNCOUPLED Uncoupling the port power allows you to apply different power levels at each port In Figure 1 51 the port 1 power is set to 25 dBm for the gain measurement S54 and the port 2 power is set to 0 dBm for the reverse isolation measurement Sj 3 Press Trans FWD S21 B R and set the power level for port 1 4 Press Trans REV S12 AR and set the power level for port 2 5 Perform an error correction and connect the amplifier to the network analyzer Refer to the Chapter 5 Optimizing Measurement Results for error correction procedures 6 Press DUAL QUAD SETUP DUAL CHAN ON You can view both measurements simultaneously by using the dual channel display mode Refer to Figure 1 51 If the port power levels arein different power ranges one of the displayed measurements will not be continually updated and the annotation tsH will appear on the left side of the display Refer to Source Attenuator Switch Protecti on on page 7 13 for information on how to override this state NOTE To obtain best accuracy you should set the power levels prior to performing the calibration However the analyzer com
284. eration by pressing FREQS OFFSON Notice in this high side LO down conversion configuration the analyzer s source is actually sweeping backwards as shown in Figure 2 13 The measurement setup diagram is shown in Figure 2 14 Notethe RF frequency values are shown in this illustration Figure 2 13 Diagram of Measurement F requencies LO LOW PASS FILTER N IF RF 100 MHz 350 550 650 900 1 GHz pg6155d Figure 2 14 Measurement Setup from Display NETWORK ANALYZER FREQ OFFS ON off LO MENU DOWN CONVERTER SA RUN UP CONVERTER RF LO RF lt LO Start 100 MHz VIEW Stop 350 MHz MEASURE RETURN Start 900 MHz Stop 650 MHz Fixed LO 1 GHz LO Power 13 dBm pa533e 2 16 Making Mixer Measurements Conversion Loss Using the Frequency Offset Mode 5 To view the conversion loss in the best vertical resolution press Scale Ref AUTOSCALE Figure 2 15 Conversion Loss Example Measurement CH1 R log MAG 1 dBm REF 7 dBm PRm FC Car T Ofs TO Sell bu 9 START 100 000 ODOO MHz STOP 350 000 O00 MHz pa5190e In this measurement you set theinput power and measured the output power Figure 2 15 shows the absolute loss through the mixer versus mixer output frequency If the mixer under test contained built in amplification then the measurement results would have shown conversion gain Making Mixer Measurements High Dynamic Rang
285. erations according to the instructions from the front panel or over GPIB The formatted data is then displayed The data processing sequence is described in Processing on page 7 6 7 4 Operating Concepts System Operation Required Peripheral Equipment M easurements require calibration standards for vector accuracy enhancement error correction and cables for interconnections Model numbers and details of compatible power splitters calibration kits and cables are provided in Options and Accessories chapter of the reference guide 7 5 Operating Concepts Processing Processing The analyzer s receiver converts the R A and B input signals into useful measurement information This conversion occurs in two main steps Theswept high frequency input signals aretranslated to fixed low frequency IF signals using analog sampling or mixing techniques Refer tothe service guide for more details on the theory of operation ThelF signals are converted into digital data by an analog to digital converter ADC From this point on all further signal processing is performed mathematically by the analyzer microprocessors The following paragraphs describe the sequence of math operations and the resulting data arrays as theinformation flows from the ADC tothe display They provide a good foundation for understanding most of the response functions and the order in which they are performed Figure 7 2 is a data process
286. ered in any particular order The analyzer sorts the segments automatically and lists them on the display in order of increasing start frequency even if they are entered in center span format If duplicate frequencies exist the analyzer makes multiple measurements on identical points to maintain the specified number of points for each subsweep The data is shown on the display as a singletracethat is a composite of all data taken Thetrace may appear uneven because of the distribution of the data points but the frequency scale is linear across the total range Once the list frequencies have been defined or modified the list frequency sweep mode can be selected with the LIST FREQ STEPPED softkey in the sweep type menu The frequency list parameters can also be saved with an instrument state Swept List Frequency Sweep Hz The LIST FREQ SWEPT softkey activates a swept list frequency sweep one of two list frequency sweep modes The swept list mode allows the analyzer to sweep a list of arbitrary frequency points which are defined and modified in a way similar to the stepped list mode However this mode takes data while sweeping through the defined frequency points increasing throughput by up to 6 ti mes over a stepped sweep I n addition this mode allows the test port power and IF bandwidth to be set independently for each segment that is defined The only restriction is that you cannot specify overlapping frequency segments Similar to
287. es activated by pressing the S111 PORT or S221 PORT softkey within the calibrate menu provide directivity source match and frequency response vector error correction for reflection measurements These procedures provide high accuracy reflection measurements of one port devices or properly terminated two port devices Full Two Port Calibration The full two port calibration activated by pressing the FULL 2 PORT softkey within the calibrate menu provides directivity source match load match isolation and frequency response vector error correction in both forward and reverse directions for transmission and reflection measurements of two port devices This calibration provides the best magnitude and phase measurement accuracy for both transmission and reflection measurements of two port devices and requires an S parameter test set In this type of calibration both forward and reverse measurements must be made You havethe option of setting the ratio of the number of forward or reverse sweeps versus the number of reverse or forward sweeps To access this function press MORE TESTSET SW and enter the number of sweeps desired TRL LRM Two Port Calibration The TRL LRM two port calibration activated by pressing the TRL LRM 2 PORT softkey within the calibration menu provides the ability to make calibrations using the TRL or LRM method For more information refer to TRL LRM Calibration on page 7 66 E CAL The E Cal cal
288. es all other selected options Files with s1 and s2 File Extensions There are two type of files with s1 and s2 file extensions Thereis FileXX s1 or s2 and DataXX s1 or s2 With DATA ONLY on OFF Turned Off FileXX s1 is an ASCII file in Touchstone S2P format Basically this is a file in real imaginary spreadsheet type format with five columns frequency in the first column S11 in the second column S21 in the third S12 in the fourth and S22 in the fifth column If Channel 2 is active the same type of file is produced but the file extension is s2 If dual display is on both s1 and s2 are produced These Touchstone S2P files are only produced when a full 2 port calibration is active and SAVE USING ASCII is selected The effects of port extensions and electrical delay if they are turned on are included in the data With DATA ONLY ON off Turned On DataXX s1 is also an ASCII file in Touchstone S2P format As with FileXX s1 DataXX s1 is a five column real imaginary spreadsheet type format where the columns are used the same as FileXX s1 If Channel 2 is active the same type of file is produced but the file extension is s2 If dual display is on both s1 and s2 are produced These Touchstone S2P files are only produced when a full 2 port calibration is activeand SAVE USING ASCII is selected The effects of port extensions and electrical delay if they are turned on are included in the data 4 47 Printing Plotting and S
289. est Select LOG FREQ for the fastest sweep when the frequency points of interest arein the lower part of the frequency span selected Optimizing Measurement Results Increasing Sweep Speed To View a Single Measurement Channel Viewing a single channel will increase the measurement speed if the analyzer s channels arein alternate or uncoupled mode 1 Press DUAL QUAD SETUP DUAL CHAN on OFF AUX CHAN on OFF 2 Press and to alternately view the two measurement channels f you must view both measurement channels simultaneously with dual channel use the chop sweep mode explained next 3 If you want to view channel 3 or channel 4 press or Chan 4 This will always result in a dual trace display of channel 1 and channel 3 or channel 2 and channel 4 To return to a single trace display press DUAL QUAD SETUP AUX CHAN on OFF To Activate Chop Sweep Mode You can use the chop sweep mode to make two measurements at the same time For example the analyzer can measure S11 and S21 simultaneously You can activate the chop mode by pressing or by pressing MORE CHOPAandB While Chop mode is the fastest way to measure devices some components such as filters with very high attenuation may require measurement in Alternate mode See ncreasing Dynamic Range on page 5 14 To Use External Calibration Off loading the error correction process to an external PC increases throughput on the network analyzer This can be
290. esults and the module s premeasured calibration data DATA displays a single trace representing only the measured E Cal results MEM displays a singletrace representing only the module s premeasured calibration data AUTO SCALE Changes scale and reference values to bring the trace data in view on the display The analyzer determines the smallest possible scale factor that will put all displayed data onto 8096 of the vertical graticule The reference value is chosen to put the trace in center screen RETURN Returns to the ECal Confidence Check menu NOTE When returning to the Confidence Check menu from the ECal Service menu press the SET CONF STANDARD softkey on the ECal Confidence Check menu If this softkey is not pressed the confidence check information displayed may not be accurate 6 70 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Adapter Removal Using ECal A device under test DUT whose connectors cannot be connected directly to a test configuration is considered to be a noninsertable device See Figure 6 25 Noninsertable devices can be caused because the DUT has Input or output connectors with the same sex connector as the test configuration Input or output connectors of a different connector type than the test configuration Figure 6 25 Noninsertable Device NETWORK ANALYZER Reference Reference Port 1 Port 2 pa593e The adapter removal calibration technique may be used with th
291. eter documentation for its calibration procedures Conversion Loss Using the Frequency Offset Mode Conversion loss is the measure of efficiency of a mixer It is the ratio of side band IF power to RF signal power and is usually expressed in dB The mixer translates the incoming signal RF to a replica IF displaced in frequency by the local oscillator LO Frequency translation is characterized by a loss in signal amplitude and the generation of additional sidebands For a given translation two equal output signals are expected a lower sideband and an upper sideband Figure 2 9 An Example Spectrum of RF LO and IF Signals Present in a Conversion Loss Measurement 4 I CONVERSION LOSS POWER LEVEL fip fap fio flo fnr fie trF Lo FREQUENCY pg694d The following procedure describes the R channel swept IF frequency conversion loss measurement of a broadband component mixer with power meter calibration For this example we will use the following example settings For your measurement you will need to use settings specific to your measurement Settings Used for this Example e LO frequency of 1 GHz 1000 M Hz RF start frequency of 650 MHz RF stop frequency of 900 MHz F start frequency of 100 MHz F stop frequency of 350 MHz RF LO e Down convertor TIP For ease of use the RF frequency range needs to be the same as the network analyzer s frequency range limit Making Mixer Measurem
292. etitling press DONE Naming Files Generated by a Sequence The analyzer can automatically increment the name of a file that is generated by a sequence using a loop structure See example Loop counter decision making on page 1 112 To access the sequence file name menu press FILE UTILITIES e SEQUENCE FILENAMING This menu presents two choices FILE NAME FILEO supplies a name for the saved state or data file This also brings up the Title File Menu e PLOT NAME PLOTFILE supplies a name for the plot file generated by a plot to disk command This also brings up the Title File Menu These keys show the current file name in the 2nd line of the softkey When titling a filefor usein a loop function you arerestricted to only 2 characters in the file name due to the 6 character length of the loop counter keyword LOOP When the fileis actually written the LOOP keyword is expanded to only 5 ASCII characters digits resulting in a 7 character file name After entering the 2 character file name press LOOP COUNTER DONE 1 102 Making Measurements Using Test Sequencing Storing a Sequence on a Disk 1 Toformat a disk refer to Chapter 4 Printing Plotting and Saving Measurement Results 2 To save a sequence to the internal disk press MORE STORE SEQ TO DISK and select the particular sequence softkey The disk drive access light should turn on briefly When it goes out the sequence has been saved
293. example enter TRL KIT1 DONE 19 To save the newly defined kit into nonvolatile memory press KIT DONE MODIFIED SAVE USER KIT NOTE Refer to Saving Modified Calibration Kits to a Disk on page 7 65 for information about saving modified calibration kits along with calibration data and instrument states to a disk 6 53 Calibrating for Increased Measurement Accuracy Calibrating for Non Coaxial Devices Perform the TRL Calibration 1 Press CAL KIT SELECT CAL KIT USER KIT RETURN RETURN CALIBRATE MENU TRL LRM 2 PORT To measure the TRL THRU connect the zero length transmission line between the two test ports 3 To make the necessary four measurements press THRU THRU 4 To measure the TRL SHORT connect the short to PORT 1 and press S11 REFL TRLSHORT Connect the short to PORT 2 and press 22 REFL TRLSHORT 6 Tomeasurethe TRL LINE disconnect the short and connect the TRL linefrom PORT 1to PORT 2 7 Press LINE MATCH DO BOTH FWDHREV 8 Theline data is measured and the LN MATCH1LINE 29d LN MATCH2LINE softkey labels are underlined 9 To measurethe ISOLATION dass press ISOLATION m You could choose not to perform the isolation measurement by pressing OMIT ISOLATION DONE TRL LRM NOTE You should perform the isolation measurement when the highest dynamic range is desired To perform the best isolation measurements you should reduce the system bandwidth or activate the averaging func
294. ference Port 2 7 Connect the ECal module between adapter A3 and adapter A2 8 Press Cal ECal MENU pl510ets 9 Press FULL 2 PORT to perform the second 2 port error correction using the E Cal module 10 Savethe results to disk Name the file PORT 2 11 Determine the electrical delay of adapter A3 If you have adapter specifications that identify the electrical delay you may use that information and continue with Remove the Adapter on page 6 76 If you do not know the delay of adapter A3 perform the Determine the Electrical Delay procedure on page 6 75 6 74 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal Determine the Electrical Delay This procedure determines the electrical delay of adapter A3 using a short 1 Refer to Figure 6 29 while performing the steps in this procedure 2 Perform a 1 port calibration at Reference Port 1 Refer to Step A of Figure 6 29 This 1 port calibration can either be a manual calibration or an ECal Figure 6 29 Determining the Electrical Delay Setup NETWORK ANALYZER NETWORK ANALYZER Reference Reference Reference Port 1 Port 1 Port 2 Step A Step B pl512ets 3 Connect the A3 adapter to Reference Port 1 as shown in Step B of Figure 6 29 Connect a short to the open end of the A3 adapter 4 Measurethe delay of the adapter by pressing DELAY 5 Dividethe resulting delay measurement by 2 to determine the delay of the thru and the short in
295. ff rate and sidelobe levels A detailed discussion of gating and gate shape selections is located in Gating on page 3 35 and Selecting Gate Shape on page 3 36 The passband ripple and sidelobe levels are descriptive of the gate shape The cutoff timeis the time between the stop time 6 dB on the filter skirt and the peak of the first sidelobe and is equal on theleft and right side skirts of thefilter The minimum gate span is just twice the cutoff time because it has no passband 3 7 Making Time Domain Measurements Making Transmission Response Measurements Figure 3 5 Gate Shape CH1 A R log MAG 10 dB REF 70 dB hp Gat Hid P CH1 START 7 ns STOP 7 ns Toseethe effect of the gating in the frequency domain press TRANSFORM MENU TRANSFORM OFF Scale Ref AUTO SCALE DATAMEM DISPLAY DATA AND MEMORY TRANSFORM MENU SPECIFY GATE GATE OFF This places the gated response in memory Figure 3 6 shows the effect of removing the RF leakage and thetriple travel signal path using gating By transforming back to the frequency domain we seethat this design change would yield better out of band rejection Figure 3 6 Gating Effects in a Frequency Domain Example Measurement CH1 amp 5 8M log MAG 19 dB REF 11 dB 1 63 488 dB iis 80 eda MHz L START 119 800 8A MHz STOP 149 88a 8280 MHz aw000024 Making Time
296. front panel knob to increase the electrical length until you achieve the best flat line as shown in Figure 1 35 1 44 Making Measurements Measuring Electrical Length and Phase Distortion The measurement value that the analyzer displays represents the electrical length of your device relative to the speed of light in free space The physical length of your device is related tothis value by the propagation velocity of its medium NOTE Velocity factor is the ratio of the velocity of wave propagation in a coaxial cable to the velocity of wave propagation in free space Most cables have a relative velocity of about 0 66 the speed in free space This velocity depends on the relative permittivity of the cable dielectric e as 1 Velocity Factor Fe You could change the velocity factor to compensate for propagation velocity by pressing MORE VELOCITY FACTOR enter the value xt This will allow the analyzer to accurately display the equivalent distance that corresponds to the entered electrical delay Figure 1 35 Example Best Flat Line with Added Electrical Delay CH1 Sg phase 100 REF 0 4_ 83 203 wa ae ae odo mHz CTRECAL DELAY Ded 5962 up 478 52 m CENTER 134 000 000 MHz SPAN 2 000 000 MHz pa5104e 8 Todisplay the electrical length press ELECTRICAL DELAY In this example there is a large amount of electrical del
297. g a specific measurement as you step through a series of CW frequencies or dc bias levels For an example application see Fixed IF Mixer Measurements on page 2 24 1 To create a sequence that will set the initial value of the loop counter and call the sequence that you want to repeat press NEW SEQ MODIFY SEQ SEQUENCE 1SEQ1 SPECIAL FUNCTIONS DECISION MAKING LOOP COUNTER DO SEQUENCE SEQUENCE 2 DONE SEQ MODIFY This will create a displayed list as shown SEQUENCE LOOP 1 Start of Sequence LOOP COUNTER 10x1 DO SEQUENCE SEQUENCE 2 1 114 Making Measurements Using Test Sequencing to Test a Device To create a second sequence that will perform a desired measurement function decrement the loop counter and call itself until the loop counter value is equal to zero press NEW SEQ MODIFY SEQ SEQUENCE 2 SEQ2 Trans FWD S21 B R AUTO SCALE SEARCH MAX SPECIAL FUNCTIONS DECISION MAKING DECR LOOP COUNTER IF LOOP COUNTER O SEQUENCE 2 SEQ2 DONE SEQ MODIFY This will create a displayed list as shown SEQUENCE LOOP 2 Start of Sequence Trans FWD S21 B R SCALE DIV AUTO SCALE MKR Fctn SEARCH MAX DECR LOOP COUNTER IF LOOP COUNTER 0 THEN DO SEQUENCE 2 Torun theloop sequence press SEQUENCE 1SEQ1 Generating Files in a Loop Counter Example Sequence This example shows how to increment the names of files that are generated by a sequence with a l
298. g Concepts TRL LRM Calibration LINE MATCH LINE LINE MATCH MATCH I must be identical on both ports If the reflect is used to set the reference plane the phase response must be well known and specified Zo of the line establishes the reference impedance of the measurement i e 419 S22 0 The calibration impedance is defined to be the same as Zo of the line If the Zp is Known but not the desired value i e not equal to 50 Q the SYSTEMS Zp selection under the TRL LRM options menu is used Insertion phase of the line must not be the same as the thru zero length or non zero length The difference between the thru and line must be between 20 and 160 n x 180 Measurement uncertainty will increase significantly when the insertion phase nears 0 or an integer multiple of 180 Optimal line length is 1 4 wavelength or 90 of insertion phaserelative tothethru at the middle of the desired frequency span Usable bandwidth for a singlethru line pair is 8 1 frequency span start frequency Multiple thru line pairs Zg assumed identical can be used to extend the bandwidth to the extent transmission lines are available Attenuation of the line need not be known Insertion phase must be known and specified within 1 4 wavelength or 90 Zo of the match establishes the reference impedance of the measurement I must be identical on both ports Fabricating and defining calibration standards for TRL LRM
299. ge pen 7 to black 5 After all selections have been made the file is imported and rendered in a small graphics frame which can be sized to the page by grabbing one of the nodes and stretching the box as required You will notice that the annotation around the display is not optimum as the Ami Pro filter does not accurately import the HPGL command to render text Using Freelance To view plot files in Freelance perform the following steps 1 From the FILE pull down menu select IMPORT 2 Set thefiletypein the dialog box to HGL NOTE Thenetwork analyzer does not use the suffix H GL so you may want to change the filename filter to or some other pattern that will allow you to locate the files you wish to import 3 Click OK to import the file You will noticethat when thetrace is displayed the text annotation will be illegible You can easily fix this with the following steps a Fromthe TEXT pull down menu select F ONT b Select the type face and size Fourteen point text is a good place to start c Click OK toresizethe font To change the font color just do it immediately after you resize the font using the same dialog box 4 21 Printing Plotting and Saving Measurement Results Outputting Plot Files from a PC to a Plotter Converting HPGL Files for Use with Other PC Applications A utility can convert hpgl or fp files to other PC applications This utility named hp2xx is available to be downloaded with
300. gi es products For any assistance contact your nearest Agilent Technologies Sales and Service Office Shipment for Service If you are sending the instrument to Agilent Technologies for service ship the analyzer to the nearest service center for repair induding a description of any failed test and any error message Ship the analyzer using the original or comparable antistatic packaging materials 8 2 Table 8 1 Contacting Agilent Online assistance www agilent com find assist United States tel 1800 452 4844 New Zealand tel 0 800 738 378 fax 64 4 495 8950 Latin America tel 305 269 7500 fax 305 269 7599 J apan tel 81 426 56 7832 fax 81 426 56 7840 Safety and Regulatory Information General Information Canada tel 1877 894 4414 fax 905 282 6495 Europe tel 31 20 547 2323 fax 4331 20 547 2390 Australia tel 1800 629 485 fax 461 3 9210 5947 Asia Call Center Numbers Country Phone Number Fax Number Singapore 1 800 375 8100 65 836 0252 Malaysia 1 800 828 848 1 800 801664 Philippines 632 8426802 632 8426809 1 800 16510170 PLDT 1 800 16510288 PLDT Subscriber Only Subscriber Only Thailand 088 226 008 outside Bangkok 66 1 661 3714 662 661 3999 within Bangkok HongKong 800 930 871 852 2506 9233 Taiwan 0800 047 866 886 2 25456723 People s Republic of China 800 810 0189 preferred 10800 650 0021 10800 650 0121
301. gnals In mixer measurements leakage signals from one mixer port propagate and appear at the other two mixer ports These unwanted mixing products or leakage signals can cause distortion by mixing with a harmonic of the analyzer s first down conversion stage To ensure successful mixer measurements the following measurement challenges must be taken into consideration Mixer Considerations Q Minimizing Source and Load Mismatches O Reducing the Effect of Spurious Responses on page 2 5 O Eliminating Unwanted Mixing and Leakage Signals on page 2 6 Analyzer Operation O How RF and IF Are Defined on page 2 7 Frequency Offset M ode Operation on page 2 10 T LO Frequency Accuracy and Stability on page 2 10 O Power Meter Calibration on page 2 10 Minimizing Source and Load Mismatches When characterizing linear devices you can use vector accuracy enhancement to mathematically remove all systematic errors including source and load mismatches from your measurement This is difficult when the device you are characterizing is a mixer wherethe input and output signals are at different frequencies Therefore source and load mismatches are not corrected for and will add to overall measurement uncertainty You should place attenuators at all of the test ports to reduce the measurement errors associated with the interaction between mixer port matches and system port matches To avoid overdriving the receiver you should giv
302. hancement When the channels are uncoupled COUPLED CH OFF there may be as many as eight raw arrays These arrays are directly accessible via GPIB Notice that the numbers here are still complex pairs Raw Arrays Raw arrays contain the pre raw data which has sampler and attenuator offset applied Vector Error correction Accuracy Enhancement Error correction is performed next if a measurement calibration has been performed and correction is activated E rror correction removes repeatable systematic errors stored in the error coefficient arrays from the raw arrays This can vary from simple vector normalization to full 12 term error correction The results of error correction are stored in the data arrays as complex number pairs These are subsequently used whenever correction is on and are accessible via GPIB If the data to memory operation is performed the data arrays are copied into the memory arrays Trace Math Operation This operation selects either the data array memory array or both to continue flowing through the data processing path In addition the complex ratio of the two data memory or the difference data memory can also be selected If memory is displayed the data from the memory arrays goes through exactly the same processing flow path as the data from the data arrays Gating Option 010 Only This digital filtering operation is associated with time domain transformation Its purpose is to mathematically
303. he cable dielectric 3 10 Making Time Domain Measurements Making Reflection Response Measurements 8 To position the marker on the reflection of interest press and turn the front panel knob or enter a value from the front panel keypad In this example the velocity factor was set to one half the actual value so the marker reads the time and distance to the reflection 9 To position a marker at each reflection of interest as shown in Figure 3 9 press MARKER2 MARKER3 MARKER 4 turning the front panel knob or entering a value from the front panel keypad after each key press Figure 3 9 Device Response in the Time Domain CHi 81 Lin MAG 5 mU REF 15 mU 4 10 391 mU 28 113 ns L IS l86 mU a 468 pc MARKER 4 P i Ai Ael mi 20 113 fs 3 z p 1 9B98 m i To 431 ns T CH1 START s STOP 35 ns aw000026 Making Time Domain Measurements Time Domain Bandpass Mode Time Domain Bandpass Mode This mode is called bandpass because it works with band limited devices Traditional TDR requires that the test device be able to operate down to dc Using bandpass mode there are no restrictions on the measurement frequency range Bandpass mode characterizes the test device impulse response Adjusting the Relative Velocity Factor A marker provides both the two way time and the two way electrical length or distance to a discontinuity The distance di
304. he first segment This is due to the narrower IF bandwidth of the third segment 300 Hz 1 69 Making Measurements Using the Swept List Mode to Test a Device Figure 1 55 Filter Measurements Using Linear Sweep and Swept List Mode Using Linear Sweep Power 0 dBm IF BW 3700 Hz CH1 Spy log MAG 11 dB REF O dB ba PRm CENTER 900 000 000 MHz SPAN 500 000 000 MHz Using Swept List Mode CH4 S24 log MAG 11 dB REF O dB ta PRm CENTER 900 000 000 MHz SPAN 500 000 000 MHz SEGMENT 1 Power 10 dBm IF BW 1000 Hz SEGMENT 3 Power 10 dBm IF BW 300 Hz SEGMENT 2 Power 10 dBm IF BW 3700 Hz 1 70 Making Measurements Using Limit Lines to Test a Device Using Limit Lines to Test a Device Limit testingis a measurement technique that compares measurement data to constraints that you define Depending on the results of this comparison the analyzer will indicate if your device either passes or fails the test Limit testing is implemented by creating individual flat sloping and single point limit lines on the analyzer display When combined these lines can represent the performance parameters for your device under test The limit lines created on each measurement channel are independent of each other This example measurement shows you how to test a bandpass filter us
305. he number of sweeps for the active display channel S44 and S254 for channel 1 in this case to update more often than the inactive display channel In this example we choose 8 updates of the forward parameters to 1 update of the reverse in channel 1 and 8 updates of the reverse to 1 update of the forward in channel 2 where the active parameters are S55 and S42 Press CONFIGURE MENU TESTSET SWCONTINUOUS GD Press CONFIGURE MENU TESTSET SWCONTINUOUS GD 1 52 Making Measurements Measuring Amplifiers Measuring Amplifiers The analyzer allows you to measure the transmission and reflection characteristics of many amplifiers and active devices You can measure scalar parameters such as gain gain flatness gain compression reverse isolation return loss SWR and gain drift versus ti me Additionally you can measure vector parameters such as deviation from linear phase group delay complex impedance and AM to PM conversion Figure 1 42 Amplifier Parameters GAIN GAIN FLATNESS GAIN DRIFT DEVIATION FROM LINEAR PHASE GROUP DELAY GAIN COMPRESSION S21 INPUT MATCH INPUT RETURN LOSS INPUT SWR AUT O INPUT RELECTION COEFFICIENT INPUT IMPEDANCE S22 OUTPUT MATCH OUTPUT RETURN LOSS OUTPUT SWR Sp OUTPUT REFLECTION COEFFICIENT REVERSE ISOLATION OUTPUT IMPEDANCE pg6137d When you are measuring a device that is very sensitive to absolute power level it is
306. hese menus or the analyzer is powered off and then on again Cycling the power changes all color adjustments to default values Once the colors are saved pressing the key does not affect the color selections Saving Modified Colors To save a modified color set press SAVE COLORS Modified colors are not part of a saved instrument state and are lost unless saved using these softkeys Once modified colors are saved they will bethe colors applied until is pushed Recalling Modified Colors To recall the previously saved color set press RECALL COLORS 1 23 Making Measurements Using Markers Using Markers The key displays a movable active marker on the screen and provides access to a series of menus to control up to five display markers for each channel Markers are used to obtain numerical readings of measured values They also provide capabilities for reducing measurement time by changing stimulus parameters searching the trace for specific values or statistically analyzing part or all of the trace Markers have a stimulus value the x axis value in a Cartesian format and a response value the y axis value in a Cartesian format In polar format the second part of a complex data pair is also provided as an auxiliary response value In Smith chart format the real and imaginary rectangle are both displayed and the effective capacitance or inductance of the imaginary part is also displayed When a marker is activated and no other
307. hetable This is due to restricted display space When analyzer port power is uncoupled the LIST POWER ON off softkey can also be set independently for each port For example you may choose to set LIST POWER ON off for forward measurements and LIST POWER on OFF for reverse measurements In this case the power would be set according to values in thelist when measuring the forward parameters When measuring the reverse parameters the power would be set according to the normal analyzer power controls Setting Segment IF Bandwidth To enable the SEGMENT IF BW function you must first select LIST IF BW ON off in the edit subsweep menu List IF bandwidth is off by default and the asterisks that appear in the IF BW column of the list table indicate that the IF bandwidth for the sweep is being set by the normal analyzer controls 7 18 Operating Concepts Sweep Types Narrow IF bandwidths require more data samples per point and thus slow down the measurement time Selectable IF bandwidths can increase the throughput of the measurement by allowing you to specify narrow bandwidths only where needed Power Sweep dBm The POWER SWEEP softkey turns on a power sweep mode that is used to characterize power sensitive circuits In this mode power is swept at a single frequency from a start power value to a stop power value selected using the and keys and the entry block This featureis convenient for such measurements as gain compression or AGC
308. his Chapter Th is chapter contains the following An introduction to time domain measurements Example procedures for making time domain transmission and reflection response measurements Information on the following time domain concepts Time Domain Bandpass M ode on page 3 12 Time Domain Low Pass Mode on page 3 15 Transforming CW Time Measurements into the F requency Domain on page 3 22 Masking on page 3 26 Windowing on page 3 27 Range on page 3 30 Resolution on page 3 32 Gating on page 3 35 3 2 Making Time Domain Measurements Introduction to Time Domain Measurements Introduction to Time Domain Measurements Theanalyzers with Option 010 allow you to measurethe time domain response of a device Time domain analysis is useful for isolating a device problem in time or in distance Time and distance are related by the velocity factor of your device under test DUT which is described in Time Domain Bandpass Mode on page 3 12 Theanalyzer measures the frequency response of your device and uses an inverse Fourier transform a mathematical calculation to convert the frequency domain information into the time domain with time as the horizontal display axis The analyzer s internal computer makes this mathematical calculation using the chirp Z Fourier transform technique The resulting measurement is the fully error corrected ti me domain reflection or transmission response of
309. his feature will not work for all printers due to differences in printer resolution Figure 4 2 Printing Two Measurements A CH1 S11 Re 1 mU REF 4 mU 1 7 8215 mU hp 1 311 ns Cor MARKER 1 1321 ns 396 03 mn is CH1 START 1 078 ns STOP 1 505 ns CH S11 Re 1 mU REF 4 mU 1 78215 mU hp 7 341 nsl Cor MARKER 1 327 ns 396 03 m CH1 START 1 078 ns STOP 1 505 ns pg6148d Printing Plotting and Saving Measurement Results Configuring a Plot Function Configuring a Plot Function All copy configuration settings are stored in non volatile memory Therefore they are not affected if you press or switch off the analyzer power Peripheral Interface Recommended Cables Parallel 92284A GPIB 10833A 33B 33D Serial 24542G 1 Connect the peripheral to the interface port using the recommended cable from the following list Figure 4 3 Peripheral Connections to the Analyzer GPIB Parallel RS 232 Port Serial Port If You Are Plotting to an HPGL 2 Compatible Printer 2 Press SET ADDRESSES PLTR PORT andthen press PLTR TYPE until HPGL PRT appears Information regarding a printer compatibility guide an up to date list of printers that are compatible with the network analyzer is available in Printing or Plotting Your Measurement Results on page 4 3 3 Configure the analyz
310. hoices Choose MARKERS CONTINUOUS if you want the analyzer to place markers at any point on the trace by interpolating between measured points This default mode allows you to conveniently obtain round numbers for the stimulus value Choose MARKERS DISCRETE if you want the analyzer to place markers only on measured trace points determined by the stimulus settings This may bethe best mode to use with automated testing using a computer or test sequencing because the analyzer does not interpolate between measured points 1 24 Making Measurements Using Markers NOTE Using MARKERS DISCRETE will alsoaffect marker search and positioning functions when the value entered in a search or positioning function does not exist as a measurement point The marker will be positioned to the closest adjacent point that satisfies the search or positioning value To Activate Display Markers Toswitch on marker 1 and make it the active marker press MARKER 1 The active marker is identified on the analyzer display with the following symbol V The active marker stimulus value is displayed in the active entry area You can modify the stimulus value of the active marker using the front panel knob or numerical keypad All of the marker response and stimulus values are displayed in the upper right corner of the display Figure 1 12 Active Marker Control Example CHi 82 tog MAG 19 dBy REF 58 dB 1 89 51 dB 125 45 eda Mhz
311. hows the non random crosstalk data NOTE If you are performing an ECal using two modules selecting either option sets up the option to be performed with both modules To Select the Manual Thru Calibration Option 1 Toselect the manual thru calibration option press ECal MENU CONFIGURE 1 2 Press MAN L THRU on OFF until ON is selected 3 Press RETURN 4 Continue with step 2 of Perform the Calibration on page 6 64 To Select the Isolation Calibration Option 1 To select the isolation calibration option press ECal MENU CONFIGURE 2 Press OMIT ISOLATION ON off until OFF is selected The isolation measurement is normally off Therefore the default setting for the OMIT ISOLATION ON off softkey is ON When isolation is not omitted OMIT ISOLATION on OFF isolation standards are measured 3 Press ISOLATION AVERAGES enter the isolation averages numeric value on the front panel keypad and then press x1 NOTE Theisolation averaging default is set to take 10 sweeps This isolation averaging valueis less than the network analyzer default sweep averaging value of 16 4 Press RETURN 5 Continue with step 2 of Perform the Calibration 6 63 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal Perform the Calibration l Press Cal ECal MENU When E Cal is first selected or when you select module A or module B thereis a small initial delay sothat the network a
312. ibration INPUT PORTS B MORE TITLE ERASE TITLE Input as title POW LEV 6DBM DONE Seq SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL MORE TITLE ERASE TITLE Input as title FREQ MODE CW CW 100MHZ DONE SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL CALIBRATE MENU RESPONSE THRU Prompting the User to Connect a Mixer to the Test Setup MORE TITLE ERASE TITLE Input astitle CONNECT MIXER DONE SPECIAL FUNCTIONS PAUSE 2 26 Making Mixer Measurements Fixed IF Mixer Measurements Initializing a Loop Counter Value to 26 SPECIAL FUNCTIONS DECISION MAKING LOOP COUNTER REFERENCE POSITION 0 REFERENCE VALUE TRIGGER MENU MANUAL TRG ON POINT Addressing and Configuring the Two Sources MORE TITLE ERASE TITLE Input as title FREQ M ODE CW CW 500MHZ FREQ CW STEP 100MHZ DONE SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL MORE TITLE ERASE TITLE Input as title POW LEV 13DBM DONE SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL MORE TITLE ERASE TITLE Input as title FREQ M ODE CW CW 600MHZ FREQ CW STEP 100MHZ DONE SPECIAL FUNCTIONS PERIPHERAL GPIB ADDR TITLE TO PERIPHERAL Calling the Next Measurement Sequence DO SEQUENCE SEQUENCE 2 SEQ2 DONE SEQ MODIFY 2 27 Making Mixer Measurements Fixed IF Mixer Measurements Press NEW SEQ MODIFY SEQ SEQUENCE 1SEQ 1 and the analyzer will display the following sequence commands SEQUENCE SEQ1 Start of Sequence RECALL PRST STATE SYSTEM CONTROLLER
313. ibration The step rise time is proportional to the highest frequency in the frequency domain sweep the higher the frequency the faster the rise time The frequency sweep in Figure 3 15 is from 10 MHz to 1 GHz Figure 3 15 also illustrates the time domain low pass response of an amplifier under test The average group delay over the measurement frequency range is the difference in time between the step and the amplifier response This time domain response simulates an oscilloscope measurement of the amplifier s small signal transient response Note the ringing in the amplifier response that indicates an under damped design Making Time Domain Measurements Time Domain Low Pass Mode Figure 3 15 Time Domain Low Pass Measurement of an Amplifier Small Signal Transient Response CH1 S21 Re 1 U REF OU b 5 8464 U START 1 ne STOP 9 ne pg6196 c Interpreting the Low Pass Step Transmission Response Horizontal Axis Thelow pass transmission measurement horizontal axis displays the average transit time through the test device over the frequency range used in the measurement The response of the thru connection used in the calibration is a step that reaches 5096 unit height at approximately time 0 The rise time is determined by the highest frequency used in the frequency domain measurement The step is a unit high step which indicates noloss for thethru calibration When a device is inserted
314. ibration menu is activated by pressing E CAL MENU in the calibration menu The E Cal Electronic Calibration system determines systemic errors of the analyzer through a one time connection of an E Cal moduleto the network analyzer ports The random error of connector repeatability is reduced substantially through a one ti me connecti on when compared to frequent connections and disconnections of the conventi onal short open load methods 7 55 Operating Concepts Modifying Calibration Kits Modifying Calibration Kits Modifying calibration kits is necessary only if unusual standards such as in TRL are used or the very highest accuracy is required Unless a calibration kit model is provided with the calibration devices used a solid understanding of error correction and the system error model are absolutely essential to making modifications You may use modifications to a predefined calibration kit by modifying the kit and saving it as a user kit The original predefined calibration kit will remain unchanged Before attempting to modify calibration standard definitions you should read Application Note 8510 5A to improve your understanding of modifying calibration kits The part number of this application note is 5956 4352 Although the application note is written for the 8510 family of network analyzers it also applies to this network analyzer Several situations exist that may require a user defined calibration kit A calibration i
315. icrowave cable as appropriate connect the other port of the ECal module totest port 2 of the analyzer Select the ECal Options In addition to the standard ECal method there are two options that you may want to use when performing the electronic calibration They are ECal using a manual thru Calibration using a manual thru is more accurate than calibrating using the thru internal to the ECal module A zero length thru is created by connecting the two test port cables together The improved loss of the manual thru compared to the E Cal module s thru increases the accuracy of other error terms in the correction The accuracy of the overall calibration is improved Manual thrus can only be used with ECal modules having connectors of the opposite sex 6 62 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal ECal usingisolation averaging During the isolation measurement portion of ECal you are actually measuring instrument crosstalk Typically the data during this measurement is near the noise floor See also Omitting Isolation Calibration on page 6 4 When the crosstalk is near or in the noise floor one way to reduce the noiseis to turn on the isolation averaging When the random noise of the instrument is averaged its magnitude declines As the energy of the trace is averaged the displayed data becomes smoother When the random noise is reduced the network analyzer display s
316. ide the gate are mathematically removed The gate s start and stop flags define the region where gating is on 3 35 Making Time Domain Measurements Gating Figure 3 27 Gate Shape CH1 A R log MAG 10 dB REF 70 dB p Got A Hid p Hs CH1 START 7 ns STOP 7 ns pg6121d Selecting Gate Shape The four gate shapes available are listed in Table 3 4 Each gate has a different passband flatness cutoff rate and sidelobe levels Table 3 4 Gate Characteristics Gate Shape Passband Ripple Sidelobe Levels Cutoff Time Minimum Gate Span Gate Span Minimum 0 10 dB 48 dB 1 4 F req Span 2 8 F req Span Normal 0 10 dB 68 dB 2 8 F req Span 5 6 F req Span Wide 0 10 dB 57 dB 4 4 Freq Span 8 8 Freq Span Maximum 0 10 dB 70 dB 12 7 Freg Span 25 4 Freq Span Note With 1601 frequency points gating is available only in the bandpass mode The passband ripple and sidelobe levels are descriptive of the gate shape The cutoff time is the time between the stop time 6 dB on the filter skirt and the peak of the first sidelobe and is equal on the left and right side skirts of the filter As shown in Table 3 4 the minimum gate span is just twice the cutoff time because it has no passband Always choose a gate span wider than the minimum For most applications do not be concerned about the minimum gate span simply use the knob
317. ign the Standards to the Various LRM Classes 8 Toassign the calibration standards to the various TRL calibration classes press CAL KIT MODIFY SPECIFY CLASS MORE MORE TRL REFLECT 9 Since you previously designated standard 1 for the REFLECT standard press 10 Since you previously designated standard 3 for the LINE MATCH standard press TRL LINE OR MATCH 11 Since you previously designated standard 4 for the THRU LINE standard press TRL THRU 12 To complete the specification of class assignments press SPECIFY CLASS DONE Label the Classes NOTE To enter the following label titles an external keyboard may be used for convenience 13 Press LABEL CLASS MORE MORE 14 Change the label of the TRL REFLECT class to LRMSH ORT 15 Change the label of the TRL LINE OR MATCH dass to URMLOAD 16 Change the label of the TRL THRU dass to URMTHRU 17 Press LABEL CLASS DONE Label the Calibration Kit 18 Press LABEL KIT and create a label up to 8 characters long For this example enter LRM KIT1 and press DONE 19 To save the newly defined kit into nonvolatile memory press KIT DONE MODIFIED SAVE USER KIT NOTE Refer to Saving Modified Calibration Kits to a Disk on page 7 65 for information about saving modified calibration kits along with calibration data and instrument states to a disk 6 57 Calibrating for Increased Measurement Accuracy LRM Error Correction Perform the LRM Calibration 1 You must havea
318. in the following section These functions check a condition and jump to a specified sequence if the condition is true The sequence called must be in memory A sequence call is a one way jump A sequence can jump to itself or to any of the other five sequences currently in memory U se of these features is explained under the specific softkey descriptions Decision Making Functions Decision making functions jump to a softkey location not to a specific sequence title Limit test loop counter and do sequence commands jump to any sequence residing in the specified sequence position 1 through 6 These commands do not jump to a specific sequence title Whatever sequence is in the selected softkey position will run when these commands are executed Having a sequence jump to itself A decision making command can jump to the sequence it is in When this occurs the sequence starts over and all commands in the sequence are repeated This is used a great deal in conjunction with loop counter commands See the loop counter description that follows TTL input decision making TTL input from a peripheral connected tothe parallel port in the GPIO mode can be used in a decision making function Refer to The GPIO Mode on page 1 106 Limit test decision making A sequence can jump to another sequence or start over depending on the result of a limit test When entered into a sequence the IF LIMIT TEST PASS and IF LIMIT TEST FAIL commands require you to en
319. ince all of the significant systematic errors are reduced This method is implemented in the form of the S11 1 port S55 1 port and full 2 port calibration selections In all measurement environments you must provide calibration standards for the desired calibration to be performed The advantage of TRL is that only three standards need to be characterized as opposed to 4 in the traditional open short load and thru full 2 port calibrations Further the requirements for characterizing the T R and L standards are less stringent and these standards are more easily fabricated 7 66 Operating Concepts TRL LRM Calibration TRL Terminology Notice that the letters TRL LRL LRM etc are often interchanged depending on the standards used For example LRL indicates that two lines and a reflect standard are used TRM indicates that a thru reflection and match standards are used All of these refer to the same basic method TRL calibration is a modified form of TRL calibration It is adapted for a receiver with three samplers instead of four samplers The TRL calibration is not as accurate as the TRL calibration because it cannot isolate the source match from the load match so it assumes load match and source match are equal How TRL LRM Calibration Works The TRL LRM calibration used in the analyzer relies on the characteristic impedance of simple transmission lines rather than on a set of discrete impedance standards Since
320. ined by measuring the reflection coefficient of the thru connection Transmission signal path frequency response is then measured with the thru connected The data is corrected for source and load match effects then stored as transmission frequency response Err NOTE It is very important that the exact electrical length of the thru be known Most calibration kits assume a zero length thru For some connection types such as Type N this implies one male and one female port If the test system requires a non zero length thru for example one with two male test ports the exact electrical delay of the thru adapter must be used to modify the built in calibration kit definition of thethru Isolation Exe represents the part of the incident signal that appears at the receiver without actually passing through the test device See Figure 7 37 Isolation is measured with the test set in the transmission configuration and with terminations installed at the points where the test device will be connected Since isolation can be lower than the noise floor it is best to increase averaging by at least a factor of four during the isolation portion of the calibration The RESUME CAL SEQUENCE softkey under the menu allows a calibration sequence to resume after a change to the averaging factor If theleakage falls below the noise floor it is best to increase averaging before calibration 7 48 Operating Concepts Measurement Calibration In this case om
321. ing flow diagram that represents the flow of numerical data from IF detection to display The data passes through several math operations denoted in thefigure by singleline boxes Most of these operations can be selected and controlled with the front panel response block menus The data stored in arrays along the way and denoted by double line boxes are places in the flow path where data is accessible via GPIB Figure 7 2 Data Processing Flow Diagram A O B O OF asc H DIGITAL I mM SAMPLER IF R O FILTER RATIO CORRECTION AUX INO O Le swEEP SWEEPI M RAW DATA I ERROR Lp DATA a TRACE AVERAGING ARRAYS CORRECT ON ARRAYS MATH ERROR COEFFICIENT ere ARRAY L Bel GATING p ELECTRICAL p La TRANSFORM Som OPT 010 DELAY CONVERS LON OPT 010 FORMAT DMA L SMOOTHING H FORMAT We OFFSET amp Me DISPLAY k LCD ARRAYS SCALE MEMORY M MARKERS 6 IT TESTING pb6116d Operating Concepts Processing While only a single flow path is shown two identical paths are available corresponding to channel 1 and channel 2 Each channel also has an auxiliary channel for which the data is processed along with the primary channel s data Channel 3 is the au
322. ing the lt gt Titles A title may contain non printable or special ASCII characters if you download it from an external controller A non printable character is represented on the display as m Sequence Size A sequence may contain up to 2 kbytes of instructions Typically this is around 200 sequence command lines To esti mate a sequence s size in kbytes use the following guidelines Table 1 5 Guidelines for Determining the Size of a Sequence Type of Command Size in Bytes Typical command 2 Title string character 1 Active entry command 1 per digit Embedding the Value of the Loop Counter in a Title You can append a sequentially increasing or decreasing numeric value to the title of stored data by placing a MORE TITLE MORE LOOP COUNTER command after thetitle string You must limit thetitletothree characters if you will useit as a disk file name The three character title and five digit loop counter number reach the eight character limit for disk file names This feature is useful in data logging applications Autostarting Sequences You can define a sequence to run automatically when you apply power to the analyzer To make an autostarting sequence create a sequence in position six SEQ6 and titleit AUTO To stop an autostarting sequence press Local To stop an autostarting sequence from engaging at power on you must clear it from memory or rename it NOTE Presetting the instrument does not run the Auto S
323. ing the following procedures e creating flat limit lines creating sloping limit lines creating single point limit lines editing limit segments e running a limit test Setting Up the Measurement Parameters 1 Connect your test device as shown in Figure 1 56 Figure 1 56 Connections for SAW Filter Example Measurement NETWORK ANALYZER pa53e 2 Press and choose the measurement settings For this examplethe measurement settings are as follows Trans FWD S21 B R i AUTO SCALE 1 71 Making Measurements Using Limit Lines to Test a Device You may also want to select settings for the number of data points power averaging and IF bandwidth 3 Substitute a thru for the device and perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU 4 Reconnect your test device 5 To better view the measurement trace press Scale Ref AUTO SCALE Creating Flat Limit Lines In this example procedure the following flat limit line values are set Frequency Range Power Range 127 MHzto 140 MHz 27 dB to 21 dB 100 MHz to 123 MHz 200 dB to 65 dB 146 MHz to 160 MHz 200 dB to 65 dB NOTE The minimum value for measured data is 200 dB 1 To access the limits menu and activate the limit lines press LIMIT MENU LIMIT LINE LIMIT LINE ON EDIT LIMIT LINE CLEARLIST YES 2 Tocreate a new limit line press ADD The analyzer generates a new segment that appears on the center of the displa
324. ion Response Horizontal Axis In time domain transmission measurements the horizontal axis is displayed in units of time The time axis indicates the propagation delay through the device Note that in time domain transmission measurements the value displayed is the actual delay not twice the delay The marker provides the propagation delay in both time and distance Marker 2 in Figure 3 11 left indicates the main path response through the test device which has a propagation delay of 655 6 ns or about 196 5 meters in electrical length Marker 4 in Figure 3 11 right indicates the triple travel path response at 1 91 us or about 573 5 meters The response at marker 1 at 0 seconds is an RF feedthrough leakage path In addition to the triple travel path response there are several other multi path responses through the test device which areinherent in the design of a SAW filter Interpreting the Bandpass Transmission Response Vertical Axis In thelog magnitude format the vertical axis displays the transmission loss or gain in dB in the linear magnitude format it displays the transmission coefficient t Think of this as an average of the transmission response over the measurement frequency range 3 14 Making Time Domain Measurements Time Domain Low Pass Mode Time Domain Low Pass Mode This mode is used to simulate a traditional time domain reflectometry TDR measurement It provides information to determine the type of discontinui
325. ion on calibrating troubleshooting and servicing your analyzer TheServiceGuideis not part of a standard shipment and is available only as Option OBW or by ordering part number 08753 90485 A CD ROM with the Service Guidein PDF format is induded for viewing or printing from a PC Contents 1 Making Measurements Usa TRIS CRSBESE qu ee ee aq wexterxsex dd eee ee ee ree ee er ee 1 2 More Instrument Functions Not Described in This Guide 0 000 c eee eee 1 3 Making a Basic MeasuremieE sius c6 0 teed bee Cee ed bri de hh a Le ee ee eed dee a eS 1 4 Step 1 Connect the device under test and any required test equipment 1 4 Step 2 Choose the measurement parameters 0000 eee 1 4 Step 3 Perform and apply the appropriate error correctiOn s sssaaa cee eee eee 1 5 Step 4 Measure the device under test 0 2 0 eee 1 5 Step 5 Output the measurement results 00 c eee 1 6 Measuring Magnitude and Insertion Phase Response 0 0 e cece eens 1 7 Measuring the Magnitude Response 02 ccc eee ee eee 1 7 Measuring Insertion Phase Response 0 000 c eect ee eee 1 8 sing Display PUNCUIONS sci x YR cheater ewedigs Ee EE DEREREC Feet HISP AY YR IHREN 1 10 Tithng the c ovetchantnel DISpISy eraris ertir eed WPPEXTAG GER xd crREerqY PE ERE 1 11 Viewing Both Primary Measurement Channels else 1 12 Viewing Four Measurement Channels 00 cece eee eee 1
326. ions between the reference and test signal paths This error is a factor in both transmission and reflection measurements For further explanation of systematic error terms and the way they are combined and represented graphically in error models refer to the Characterizing Microwave Systematic Errors on page 7 41 7 40 Operating Concepts Measurement Calibration Characterizing Microwave Systematic Errors One Port Error Model In a measurement of the reflection coefficient magnitude and phase of a test device the measured data differs from the actual no matter how carefully the measurement is made Directivity source match and reflection signal path frequency response tracking arethe major sources of error See Figure 7 24 Figure 7 24 Sources of Error in a Reflection Measurement MEASUREMENT ERRORS Directivity 511A Frequency Tracking Source Match Measured Unknown ata pg649d To characterize the errors the reflection coefficient is measured by first separating the incident signal I from the reflected signal R then taking the ratio of the two values See Figure 7 25 Ideally R consists only of the signal reflected by the test device S114 for S11 actual Figure 7 25 Reflection Coefficient Incident Power I ES S 1M7 vu Reflected Power R Unknown pg650d However all of the incident signal does not always reach the unknown
327. is the vector sum of the current trace data and the data from the previous sweep A high averaging factor gives the best signal to noise ratio but slows the trace update time Doubling the averaging factor reduces the noise by 3 dB Averaging is used for ratioed measurements if it is attempted for a single input measurement eg A or B the message CAUTION AVERAGING INVALID ON NON RATIO MEASURE is displayed The effect of averaging on a log magnitude format trace is shown in Figure 7 18 NOTE If you switch power ranges with averaging on the average will restart Figure 7 18 Effect of Averaging on a Trace Chi S241 log MAG 10 dB REF 50 dB l 54 76 dB CH1 S24 log MAG 10 dB REF 50 d8 1 84 619 dB 2 255 330 odo MHz 2 258 30 odo MHz Avg 512 START 2 000 000 000 MHz STOP 2 300 000 000 MHz START 2 900 000 000 MHz STOP 2 300 000 O00 MHz pg6171 c 7 34 Operating Concepts Noise Reduction Techniques Smoothing Smoothing similar to video filtering averages the formatted active channel data over a portion of the displayed trace Smoothing computes each displayed data point based on one sweep only using a moving average of several adjacent data points for the current sweep The smoothing aperture is a percent of the swept stimulus span up to a maximum of 2096 Rather than
328. isplay 7 9 menu address 7 79 analog in 7 22 calibration kit 7 57 conversion 7 22 edit limits 7 82 edit segment 7 82 input ports menu 7 23 offset limits 7 82 segment 7 16 S parameter 7 22 stepped edit list 7 16 stepped edit subsweep 7 16 swept edit list 7 17 swept edit subsweep 7 17 microprocessor 7 4 microwave connector care 5 3 microwave systematic errors characterizing 7 41 minimizing error when using adapters 6 49 source and load mismatches 2 4 minimum allowable stop frequencies 3 16 minimum amplitude searching for 1 39 minimum bandwidth 1 93 minimum sweep time 7 11 mixer fixed IF measurements 2 24 measurement 2 3 measurement diagram using 2 15 2 21 mixing signals eliminating unwanted 2 6 mode auto sweep time 5 11 7 11 chop sweep 5 12 continuous correction 6 38 copy 7 79 external source 7 83 frequency offset 2 37 GPIO 7 80 low pass impulse 3 20 manual sweep time 7 11 network analyzer 7 83 pass control 7 78 system controller 7 78 talker listener 7 78 time domain bandpass 3 12 time domain low pass 3 15 tuned receiver 7 85 model one port error 7 41 two port error 7 46 modified colors 1 23 recalling 1 23 saving 1 23 modify colors menu 1 22 modifying cal kit through definition 6 47 command 1 100 standard definitions 6 52 modifying calibration kits 7 56 calibration kit menu 7 57 saving to a disk 7 65 verifying performance 7 64 module information
329. ites the existing file contents NOTE You cannot re save a file that contains data only You must create a new file 1 Press Save Recall SELECT DISK and select the storage device 1 INTERNAL MEMORY 1 INTERNAL DISK m EXTERNAL DISK If necessary refer to the external disk setup procedure in Saving an I nstrument State on page 4 36 2 Press RETURN and then use the 7 or X key or the front panel knob to highlight the name of the file that you want to re save 3 Press RE SAVE STATE YES DeletingaFile 1 Press SELECT DISK 2 Choose from the following storage devi ces 1 INTERNAL MEMORY 1 INTERNAL DISK 1 EXTERNAL DISK If necessary refer to the external disk setup procedure in Saving an Instrument State on page 4 36 3 Press RETURN To Delete an Instrument State File Q Press the or X keys or the front panel knob to highlight the name of the file that you want to delete 1 Press FILE UTILITIES DELETE FILE YES todelete all of the files that make up the selected instrument state To Delete all Files T Press FILE UTILITIES DELETE ALL FILES SAVE USING BINARY to delete all of the files that are on the selected storage device 4 51 Printing Plotting and Saving Measurement Results Renaming a File Renaming a File 1 Press Save Recall AUTO FEED OFF 2 Choose from the following storage devices 1 INTERNAL MEMORY 1 INTERNAL DISK m EXTERNAL DISK If necessary refer to the
330. itial sweep the initial sweep time is significant However in this mode of operation the analyzer does not require the power meter for subsequent sweeps Therefore this mode sweeps considerably faster than the continuous correction mode Figure 6 10 Sample and Sweep Mode for Power Meter Calibration NETWORK ANALYZER POWER METER Power Sensor D Connect For Initial Sweep Connect For Subsequent Sweep pa591e 1 Calibrate and zero the power meter 2 Connect the equipment as shown in Figure 6 10 6 36 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration 3 Select the analyzer as the system controller SYSTEM CONTROLLER 4 Set the power meter s address XX represents the address in the following keystrokes SET ADDRESSES ADDRESS P MTR GPIB 5 Select the appropriate power meter by pressing POWER MTR until the correct model number is displayed 436A or 438A 437 NOTE The E4418B and E4419B power meters have a 437 emulation mode This allows these power meters with an HP Agilent 848X series power sensor to be used with the network analyzer In this step when selecting a power meter choose the 438A 437 selection 6 Set test port power to the approximate desired corrected power 7 Press PWRMTR CAL and enter thetest port power level that you want at the input to your test device For example if you enter x1 the display will read CAL POWER 10 8 If you
331. ition to the previous sweep types there are also two different sweep modes These can be accessed through the correction menu by pressing MORE ALTERNATE AandB or CHOPAandB 7 19 Operating Concepts S Parameters S Parameters The key accesses the S parameter menu which contains softkeys that can be used to select the parameters or inputs that define the type of measurement being performed Understanding S Parameters S parameters scattering parameters are a convention used to characterize the way a device modifies signal flow A brief explanation of the S parameters of a two port device is provided however for additional details refer to Application Notes 95 1 and 154 S parameters are always a ratio of two complex magnitude and phase quantities S parameter notation identifies these quantities using the numbering convention S out in where the first number out refers to the test device port where the signal is emerging and the second number in is the test device port where the signal is incident For example the S parameter S5 identifies the measurement as the complex ratio of the signal emerging at the test device s port 2 to the signal incident at the test device s port 1 Figure 7 3 is a representation of the S parameters of a two port device together with an equivalent flowgraph In the illustration a represents the signal entering the device and b represents the signal emerging Note that a and b are not rel
332. itting isolation is better than measuring the isolation standards without increasing the averaging factor Figure 7 37 Isolation E xf Isolation X XF gt 0e gt a e 5 pg662d Thus there are two sets of error terms forward and reverse with each set consisting of six error terms as follows Directivity E pp forward and Epp reverse Isolation Exe and Exp Source Match Esp and Esp Load Match E p and ELp Transmission Tracking Erp and Erp Reflection Tracking Err and Enn Theanalyzer s test set can measure both the forward and reverse characteristics of thetest device without you having to manually remove and physically reverse the device A full two port error model illustrated in Figure 7 38 This illustration depicts how the analyzer effectively removes both the forward and reverse error terms for transmission and reflection measurements 7 49 Operating Concepts Measurement Calibration Figure 7 38 Full Two Port Error Model FORWARD XF 1 921A EE S 21M RF IN d gt Eory Vous vou Ec A S224 e lt j lt q 5 11M ERF 5 12A I PORT 1 PORT 2 REVERSE 521A FRR S 22M e B e gt e Y uA vise a E LR 342M 322A BR e a E 9 RF IN E TR S 42A 1 E E XR pg663d A full two port error model equations for all four S parameters of a two port device is shown in Figure 7 39 Note that the
333. ive noise reduction is the marker statistics function which computes the average value of part or all of the formatted trace 7 36 Operating Concepts Measurement Calibration Measurement Calibration Measurement calibration is an accuracy enhancement procedure that effectively removes the system errors that cause uncertainty in measuring a test device It measures known standard devices and uses the results of these measurements to characterize the system This section discusses the following topics e definition of accuracy enhancement causes of measurement errors characterization of microwave systematic errors e effectiveness of accuracy enhancement e ensuring a valid calibration e modifying calibration kits e TRL LRM calibration What Is Accuracy Enhancement A perfect measurement system would have infinite dynamic range isolation and directivity characteristics no impedance mismatches in any part of thetest setup and flat frequency response In any high frequency measurement there are measurement errors associated with the system that contribute uncertainty to the results Parts of the measurement setup such as interconnecting cables and signal separation devices as well as the analyzer itself all introduce variations in magnitude and phase that can mask the actual performance of the test device Vector accuracy enhancement also known as measurement calibration or error correction provides the means to simulate
334. ively filter signals entering the analyzer receiver Figure 2 4 Example of Conversion Loss versus Output Frequency without Correct IF Signal Path Filtering Chi R M log MAG S adaB REF O dB START 500 000 QOO MHz STOP 1 500 000 060 MHz pg 160 c Making Mixer Measurements Measurement Considerations Figure 2 5 Example of Conversion Loss versus Output Frequency with Correct IF Signal Path Filtering and Attenuation at All Mixer Ports CH1 R M log MAG 5 dB REF O gB Mig bfs STOP 1 800 000 000 MHz START 500 000 COO MHz pg l l c How RF and IF Are Defined When you choose between RF LO and RF gt LO inthe frequency offset menus the analyzer determines which direction the internal source must sweep in order to achieve the requested IF frequency For example to measure the lower sideband of a mixer where the RF signal is below the LO RF LO the internal source must sweep backwards See the examples in Figure 2 6 Making Mixer Measurements Measurement Considerations Figure 2 6 Examples of Up Converters and Down Converters RF gt LO IF RF 100 to 500 MHz 1100 to 1500 MHz MIXER INPUT MIXER OUTPUT LO 1000 MHz MIXER INPUT MIXER MIXER INPUT NPUT MIXER OUTPUT P f rT I I I I MHz o 100 500 1000 1100 1500 IF LO RF SOURCE SWEEPS FROM 100 to 500 MHz RECEIVER IS TUNED TO 1100 to 1500 MHz SOURCE SWEEPS UP IN FREQUENCY Example of an Upconverter with RF gt LO 1100 to 1500 MHz MIXER INPUT
335. l be turned off losing all settings and data that have not been saved 1 Configure the analyzer to plot to disk a Press Local SET ADDRESSES PLOTTER PORT DISK b Press SELECT DISK and select the disk drive that you will plot to e Choose INTERNAL DISK if you will plot to the analyzer internal disk drive 4 11 Printing Plotting and Saving Measurement Results Configuring a Plot Function Choose EXTERNAL DISK if you will plot toa disk drive that is external to the analyzer Then configure the disk drive as follows 1 Press CONFIGURE EXT DISK ADDRESS DISK and enter the GPIB address to the disk drive default is 00 followed by x1 2 Press DISK UNIT NUMBER and enter the drive where your disk is located followed by x1 3 If your storage disk is partitioned press VOLUME NUMBER and enter the volume number where you want to store the instrument state file 2 Press Copy PLOT The analyzer assigns the first available default filename for the displayed directory For example the analyzer would assign PLOTOOFP for a LIF format PLOTOO FP for a DOS format if there were no previous plot files saved to the disk Figure 4 4 shows the three parts of the file name that are generated automatically by the analyzer whenever a plot is requested Thetwo digit sequence number is incremented by one each time a file with a default nameis added to the directory Figure 4 4 Automatic File Naming Convention for LIF Format
336. l source The following features and limitations apply to the tuned receiver mode e Itisa fully synthesized receiver it does not phase lock to any source e tfunctions in all sweep types trequires a synthesized CW source whose timebase is input to the analyzer s external frequency reference For more information on using the tuned receiver mode refer to Tuned Receiver M ode on page 2 24 7 86 Operating Concepts Knowing the Instrument Modes Frequency Offset Operation Refer to Conversion Loss Using the F requency Offset M ode on page 2 11 for information on frequency offset operation Harmonic Operation Option 002 Only The analyzer s harmonic menu can be accessed by pressing HARMONIC MEAS The harmonic measurement mode allows you to measure the second or third harmonic as the analyzer s source sweeps fundamental frequencies above 16 MHz The analyzer can make harmonic measurements in any sweep type Typical Test Setup Figure 7 48 Typical Harmonic Mode Test Setup NETWORK ANALYZER OQo 8888 0000 Oeo 888 540000 OO oooooo O OOO o E 0000 0000 oo ooo OO Oo m Sq DEVICE UNDER TEST pg67e Single Channel Operation You can view the second or third harmonic alone by using only one of the analyzer s two channels Dual Channel Operation To make the following types of measurements uncouple channels 1 and 2 and switch on
337. lay that includes letters numbers and some symbols and they may be up to ten characters long The analyzer will prompt you to connect standards using these labels sothey should be meaningful to you and distinct for each standard By convention when sexed connector standards are labeled male m or female f the designation refers to the test port connector sex not the connector sex of the standard 7 61 Operating Concepts Modifying Calibration Kits Specify Class Menu Once a standard has been defined it must be assigned to a standard dass This is a group of from one to seven standards that is required to calibrate for a single error term The standards within a single class can be assigned to the locations listed in Table 7 2 according to their standard reference numbers A class often consists of a single standard but may be composed of more than one standard if band limited standards are used For example if there were two load standards a fixed load for low frequencies and a sliding load for high frequencies then that class would have two standards Table 7 2 Standard Class Assignments Calibration Kit Label Disk File Name Class Standard Reference Numbers Standard Class 1 2 3 4 5 6 7 8 Label S41A S4jB Siac SoA SB Seo Forward Transmission Reverse Transmission Forward Match Reverse Match Response Response and Isolation TRL
338. ld like to reference press and turn the front panel knob or enter a value from the front panel keypad 2 To measure values along the measurement data trace relative to the reference point that you set in the previous step press MKR ZERO and turn the front panel knob or enter a value from the front panel keypad 3 To movethe reference position press AMODE MENU FIXED MKR POSITION FIXED MKR STIMULUS andturn the front panel knob or enter a value from the front panel keypad 1 29 Making Measurements Using Markers Figure 1 17 Example of a Fixed Reference Marker Using MKR ZERO CH1 S2 log MAG 10 dB REF 1 14 dB 1 2 6579 dB 20 50 oda MHz PRm AREF A MARKER 1 9 fs 20 95 Mhz 1 n TTA S CENTER 125 000 MHz SPAN 188 8000 808 MHz Using the AREF FIXED MKR Key to Activate a Fixed Reference Marker 1 To set the frequency value of a fixed marker that appears on the analyzer display press AMODE MENU AREF AFIXEDMKR AMODE MENU FIXED MKR POSITION FIXED MKR STIMULUS and turn the front panel knob or enter a value from the front panel keypad The marker is shown on the display as a small delta A smaller thanA the inactive marker triangles Toset the response value dB of a fixed marker press FIXED MKR VALUE and turn the front panel knob or enter a value from the front panel keypad In a Cartesian format the setti
339. le modes For more information refer to Using Limit Lines to Test a Device on page 1 71 Limit lines and limit testing can beused simultaneously or independently If limit lines are on and limit testing is off the limit lines are shown on the display for visual comparison and adjustment of the measurement trace H owever no pass fail information is provided If limit testing is on and limit lines are off the specified limits are still valid and the pass fail status is indicated even though the limit lines are not shown on the display Limits are entered in tabular form Limit lines and limit testing can be either on or off whilelimits are defined As new limits are entered the tabular columns on the display are updated and the limit lines if on are modified to the new definitions The complete limit set can be offset in either stimulus or amplitude value Limits are checked only at the actual measured data points It is possible for a device to be out of specification without a limit test failureindication if the point density is insufficient Be sure to specify a high enough number of measurement points in the stimulus menu Limit lines are displayed only on Cartesian formats In polar and Smith chart formats limit testing of one value is available the value tested depends on the marker mode and is the magnitude or the first value in a complex pair The message NO LIMIT LINES DISPLAYED is shown on the display in polar and Smith chart form
340. lection devices such as filters with stop bands Load Match Load match error results from an imperfect match at the output of the test device It is caused by impedance mismatches between the test device output port and port 2 of the measurement system Some of the transmitted signal is reflected from port 2 back tothe test device as illustrated in Figure 7 23 A portion of this wave may bere reflected to port 2 or part may be transmitted through the device in the reverse direction to appear at port 1 If thetest device has low insertion loss for example a filter pass band the signal reflected from port 2 and re reflected from the source causes a significant error because the test device does not attenuate the signal significantly on each reflection Load match is usually given in terms of return loss in dB thus thelarger the number the smaller the error 7 39 Operating Concepts Measurement Calibration Figure 7 23 Load Match rom Load Incident Match Transmitted pb6114d The error contributed by load match is dependent on the relationship between the actual output impedance of thetest device and the effective match of the return port port 2 It is a factor in all transmission measurements and in reflection measurements of two port devices Theinteraction between load match and source match is less significant when the test deviceinsertion loss is greater than about 6 dB H owever source match and lo
341. lectric constant for microstrip is 6 5 then the effective velocity factor equals 0 39 1 square root of 6 5 Using the first equation with a velocity factor of 0 39 the initial length to test would be 1 95 cm This length provides an insertion phase at 1000 MHz of 60 degrees at 2000 MHz 120 degrees the insertion phase should be the same as the air line because the velocity factor was accounted for when using the first equation Another reason for showing this example is to point out the potential problem in calibrating at low frequencies using TRL For example one quarter wavelength is _ 7500 x VF Length cm E ms where e fc center frequency Thus at 50 MHz 7500 _ Length cm 50 MHz 150 cm or 1 5 m Such a line standard would not only be difficult to fabricate but its long term stability and usability would be questionable as well Thus at lower frequencies or very broad band measurements fabrication of a match or termination may be deemed more practical Since a termination is in essence an infinitely long transmission line it fits the TRL model mathematically and is sometimes referred to as a TRM calibration TheTRM calibration techniqueis related to TRL with the difference being that it bases the characteristic impedance of the measurement on a matched Zo termination instead of a transmission line for the third measurement standard Like the TRL thru standard the TRM THRU standard can either be of
342. led you can increase the power for channel 2 while channel 1 remains unchanged This will allow you to observe the gain compression on channel 2 l Press COUPLED CH OFF touncouplethe channels 2 Make sure that both channels must have the same number of points 3 Press MORE D2 D1TO D20ON toratio channels 1 and 2 and put the results in the channel 2 data array This ratiois applied to the complex data 4 Refer to Measuring Gain Compression on page 1 59 for the procedure to identify the 1 dB compression point 1 20 Making Measurements Using Display Functions Blanking the Display Pressing ADJUST DISPLAY BLANK DISPLAY switches off the analyzer display whileleaving theinstrument in its current measurement state This feature may be helpful in prolonging the life of the LCD in applications where the analyzer is left unattended such as in an automated test system Turning the front panel knob or pressing any front panel key will restore normal display operation Pressing FREQUENCY BLANK will blank the displayed frequency notation for security purposes The frequency labels cannot be restored except by instrument preset or turning the power off and then on 1 21 Making Measurements Using Display Functions Adjusting the Colors of the Display Setting Display Intensity To adjust the intensity of the display press ADJUST DISPLAY INTENSITY and rotate the front panel knob use the G3 keys or use the numerical keypad t
343. les between the five trace type display options The confidence check can display the measured ECal results DATA and the premeasured calibration data MEM in following five ways DATA amp MEM displays two traces representing the measured ECal results and module s premeasured calibration data trace DATA MEM displays a single trace representing the ratio of the measured E Cal results to the module s premeasured calibration data DATA MEM displays a singletrace representing the difference between the measured E Cal results and the module s premeasured calibration data DATA displays a single trace representing only the measured E Cal results MEM displays a singletrace representing only the module s premeasured calibration data 6 If you want to change the scale of the display press AUTO SCALE The AUTO SCALE softkey is located in this menu for convenience in viewing the confidence check data It acts the same as AUTO SCALE under the key 7 Review the confidence check display Figure 6 24 Confidence Check Display showing DATA amp MEM Trace Type 29 Jan 2081 16 55 42 AD sS11 amp M LOG 18 dB REF 8 dB START 050 666 606 GHz STOP 3 000 666 466 GHz 8 If you want to check other calibration S parameters or trace types repeat steps 4 through 7 9 When finished select RETURN to complete the confidence check 6 68 Calibrating for Increased Measurement Accuracy Calibrating Using Electroni
344. lists the order of keystrokes you would have to enter in order to create some of the setups without using one of the setup softkeys The keystroke entries are listed from top to bottom beneath each setup and are color coded to show the relationship between the keys and the channels For example beneath the four grid display CHAN 1 and MEAS S11 are shown in yellow Notice that in the four grid graphic Ch1 is also yellow indicating that the keys in yellow apply to channel 1 Pressing MORE HELP opens a screen which lists the hardkeys and softkeys associated with the auxiliary channels and setting up multiple channel multiple grid displays Next to each key is a description of its function Figure 1 11 4 Param Displays Menu 4 PARAMETER SHORTCUT KEYS SETUE A SETUP fh SETUP B SETUP C SETUP B Chi Ch2 Chi Ch2 Chi Che Sii 21 Sii 522 Sii S21 SETUP C 12 S12 22 S21 12 522 SETUP D Ch3 Ch4 Ch3 Ch4 Ch3 Ch4 tmatrix SETUP D e T E e m n 12 2 SC x e n bh C T 2 a ay csmi the lag Crefl trans 3 SETUP E 1 C a j F x S11 21 S12 22 e E 3 t T 4 Cforward reversed Coverlay SETUP F Chi Ch3 Qe FA 21 Ch2 i3 channel SETUP E SETUP F TUTORIAL RETURH Making Measurements Using Display Functions Using Memory Traces and Memory Math Functions The analyzer has four available memory traces one per channel Memory traces are tot
345. lose to actual operating conditions as possible 5 Makethe connections as shown in Figure 2 36 Figure 2 36 Connections for a Response Calibration NETWORK ANALYZER 20 dB pa567e 2 45 Making Mixer Measurements Isolation Example Measurements 6 Perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU 7 Makethe connections as shown in Figure 2 37 Figure 2 37 Connections for a Mixer RF Feedthrough Measurement NETWORK ANALYZER 20 dB External Source pa568e 8 Connect the external LO source to the mixer s LO port 9 The measurement results show the mixer s RF feedthrough NOTE You may see spurious responses on the analyzer trace due to interference caused by LO to IF leakage in the mixer This can be reduced with averaging or by reducing the IF bandwidth 2 46 Making Mixer Measurements Isolation Example Measurements Figure 2 38 Example Mixer RF Feedthrough Measurement CH1 B R log MAG tea 10 dB REF 20 dB START 10 000 000 MHz STOP 3 000 000 000 MHz You can measure the IF to RF isolation in a similar manner but with the following modifications Use the analyzer source as the IF signal drive View the leakage signal at the RF port 2 47 Making Mixer Measurements Isolation Example Measurements SWR Return Loss Reflection coefficient T is defined as the ratio between the reflected voltage V and incident voltage
346. mance is embedded in the module s memory Calibrating for Increased Measurement Accuracy Calibration Considerations Frequency Response of Calibration Standards In order for the response of a reference standard to show as a dot on the smith chart display format it must have no phase shift with respect to frequency Standards that exhibit such perfect response are the following e 7 mm short with no offset type N male short with no offset There aretwo reasons why other types of reference standards show phase shift after calibration Thereference plane of the standard is electrically offset from the mating plane of the test port Such devices exhibit the properties of a small length of transmission line including a certain amount of phase shift Thestandard is an open termination which by definition exhibits a certain amount of fringe capacitance and therefore phase shift Open terminations which are offset from the mating plane will exhibit a phase shift due to the offset in addition to the phase shift caused by the fringe capacitance The most important point to remember is that these properties will not affect your measurements The analyzer compensates for them during measurement As a result if these standards are measured after a calibration they will not appear to be perfect shorts or opens This is an indication that your analyzer is working properly and that it has successfully performed a calibration Figure 6
347. manently coupled to channels 1 and 2 respectively by stimulus That is if channel 1 is set for a center frequency of 200 MHz and a span of 50 MHz channel 3 will have the same stimulus values NOTE Channels 1 and 2 arereferred to as primary channels and channels 3 and 4 are referred to as auxiliary channels Channel 3 or 4 are activated when the Chan 3 or Chan 4 keys are pressed Alternatively you can enablethe auxiliary setting AUX CHAN toON For example if channel 1 is active pressing AUX CHAN toON enables channel 3 and its trace appears on the display Channel 4 is similarly enabled and viewed when channel 2 is active 1 Press to select the type of display of the data This example uses the log mag format 2 If channel 1 is not active make it active by pressing Chan 1 3 Press Display DUAL QUAD SETUP set DUAL CHAN to ON set AUX CHAN to ON andset SPLIT DISP to 4X The display will appear as shown in Figure 1 9 Channel 1 is in the upper left quadrant of the display channel 2 is in the upper right quadrant and channel 3 is in the lower half of the display 1 14 Making Measurements Using Display Functions Figure 1 9 Three Channel Display 1 Sep 1998 11 13 31 CHi LOG 9 dB REF 2 dB CH2 LOG 16 dB REF 50 dB 11 21 DUAL CHAN ON off AUX CHAN ON off ET ET TT Bh T d 3e 4 PARAM co Wt ft tt cor _ fT DISPLAYS Pt tee Pt LT LI E SPLIT DISP 1x CH3 12 2 1 CHANNEL
348. measurements transmission measurements e combined reflection and transmission measurements NOTE Although you can perform a response and isolation correction for reflection measurements we recommend that you perform an Sj one port error correction it is more accurate and just as convenient Response and Isolation Error Correction for Transmission Measurements This procedure is intended for measurements that have a measurement range of greater than 90 dB 1 Press Preset 2 Select the type of measurement you want to make Q If you want to make a transmission measurement in the forward direction S21 press Trans FWD S21 B R Q If you want to make a transmission measurement in the reverse direction S12 press Trans REV S12 A R 3 Set any other measurement parameters that you want for the device measurement power number of points IF bandwidth 4 To access the measurement correction menus press 5 f your calibration kit is different than the kit specified under the CAL KIT softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in the displayed menu refer to Modifying Calibration Kits on page 7 56 6 Toselect a response and isolation correction and to start the response portion of the calibration press CALIBRATE MENU RESPONSE amp ISOL N RESPONSE 6 17 Calibrating for Increased Measurement Accuracy Frequency Response and Isol
349. ment CAUTION Damage may result to the device under test DUT if it is sensitive to the analyzer s default output power level To avoid damaging a sensitive DUT be sure tolower the output power before connecting the DUT tothe analyzer 2 Choose the measurement parameters 3 Perform and apply the appropriate error correction 4 Measurethe device under test DUT 5 Output the measurement results This example procedure shows you how to measure the transmission response of a bandpass filter Step 1 Connect the device under test and any required test equipment Make the connections as shown in Figure 1 1 Figure 1 1 Basic Measurement Setup NETWORK ANALYZER pa53e Step 2 Choose the measurement parameters Press Preset To set preset the analyzer tothe Factory Preset conditions press the PRESET FACTORY softkey if it is not selected Then press Preset 1 4 Making Measurements Making a Basic Measurement Setting the Frequency Range To set the center frequency to 134 MHz press To set the span to 30 MHz press NOTE You could also press the and keys and enter the frequency range limits as start frequency and stop frequency values Setting the Source Power To change the power level to 5 dBm press NOTE You could also press POWER RANGE MAN POWER RANGES and select one of the power ranges to keep the power setting within the defined range Setting the Measurement To change the number of m
350. ment Alternately an externally installed switch or circuit breaker which is readily identifiable and is easily reached by the operator may be used as a disconnecting device CAUTION Before switching on this instrument make surethat the analyzer line voltage selector switch is set to the voltage of the power supply and the correct fuse is installed Assure the supply voltage is in the specified range CAUTION If this produc is to be energized via an autotransformer make sure the common terminal is connected to the neutral grounded side of the mains supply Safety and Regulatory Information Safety Considerations Servicing WARNING WARNING WARNING WARNING WARNING WARNING 8 6 No operator serviceable parts inside Refer servicing to qualified personnel To prevent electrical shock do not remove covers These servicing instructions are for use by qualified personnel only To avoid electrical shock do not perform any servicing unless you are qualified to do so The opening of covers or removal of parts is likely to expose dangerous voltages Disconnect the instrument from all voltage sources while it is being opened Adjustments described in this document may be performed with power supplied to the product while protective covers are removed Energy available at many points may if contacted result in personal injury The power cord is connected to internal capacitors that may remain live for 10
351. ments 000 cece een eee een hn 2 32 Phase M ed3surbTIeES cc0indeeh p26 ea Re E416 odbi itini RE RESP AY Seed ddan ee 2 32 Phase Linearity and Group Delay sias saetrxaq ute P ea EEE I HOGER DEO ee PES 2 32 Amplitude and Phase Tracking ccacieecdagedee ee cook GOR ERR eles EAR HORE ERR Edd 2 36 Conversion Compression Using the Frequency Offset Mode 000 ee eeae 2 37 Isolation Example Measurements is ess RR dd HERE ERI se ti iaa hrar iib a 2 42 LO TORE ISOON serika Viewed no 084d GES qerEERaereq PEG 54x eee REC ER REE ES 2 42 RF FeedrDrougl 2 10 ctew bed cR ER CER EROR ER CERE E dade keeles es LER EC E ER RC Ie 2 45 SANE V PEEDUPTE LOS ua B94 Id POS HSE WASH OPS SORA ESS e DeC redo PO 2 48 3 Making Time Domain Measurements sing This Chapter wa dicey a 8064 si ee Fees SIRE TETRA EE RED A E eS 3 2 Introduction to Time Domain Measurements 000 0c cee eee eee 3 3 Making Transmission Response Measurements 00 e cece eet tee eee 3 5 Making Reflection Response Measurements 00 000 e cece eee 3 9 Time Domain Bandpass Mode s a ERR RERERERERIEHERETSTYIATRTG PER RR ERI de ERE 3 12 Adjusting the Relative Velocity Factor cccccasaccdwde dean tirta ar airen aia 3 12 Reflection Measurements Using Bandpass Mode 20 0c cece e eens 3 12 Transmission Measurements Using Bandpass Mode slseesssss 3 14 Time Domain Low Pats MOOS airs due RR TATSEREXTATHPERSEEGESA hee RE dd E
352. menu TTL Output for Controlling Peripherals Eight TTL compatible output lines can be used for controlling equipment connected tothe parallel port By pressing TTL I O you will access the following softkeys that control the individual output bits Refer to Figure 1 76 for output bus pin locations PARALLEL OUT ALL lets you input a number 0 to 255 in base 10 and outputs it to the bus as binary SET BIT lets you set a single bit 0 7 to high on the output bus CLEAR BIT lets you set a single bit 0 7 tolow on the output bus TTL Input Decision Making Five TTL compatible input lines can be used for decision making in test sequencing For example if a test fixture is connected to the parallel port and has a micro switch that needs to be activated in order to proceed with a measurement you can construct your test sequence sothat it checks the TTL state of the input line corresponding to the switch Depending on whether the lineis high or low you can jump to another sequence To access these decision making functions press TTL I O Refer to Figure 1 76 for input bus pin locations PARALL IN BIT NUMBER lets you select the single bit 0 4 that the sequence will be looking for PARALL IN IF BIT H lets you jump to another sequence if the single input bit you selected is in a high state PARALL IN IF BIT L lets you jump to another sequence if the single input bit you selected is in a low state Pin assignments e pin lis
353. mixer conversion loss measurements Then any difference you view in responseis due to the mixers and not the measurement system Using the same measurement setup as in Phase or Group Delay Measurements on page 2 32 you can determine how well two mixers track each other in terms of amplitude and phase 1 Repeat steps 1 through 8 of the previous section PhaseLinearity and Group Delay on page 2 32 with the following exception In step 7 select PHASE 2 Oncethe analyzer has displayed the measurement results press DATA gt MEM 3 Replace the calibration mixer with the mixer under test 4 Press DATA MEM Theresulting trace should represent the amplitude and phase tracking of the two mixers Figure 2 26 Connections for an Amplitude and Phase Tracking Measurement Between Two Mixers a it NETWORK ANALYZER o 550 MHz LOW PASS N FILTER PORT Ts 10 dB MA 8523 MHz LOW PASS FILTER RF RF focal P F LF ees REFE m i CALIBR ATION MI XE E J o ax CONVERTER UNDER TEST f A im WEE n pg633e oo 7 0000 0000 0000 2 36 Making Mixer Measurements Conversion Compression Using the Frequency Offset Mode Conversion Compression Using the Frequency Offset Mode Conversion compression is a measure of the maximum RF input signal level where the mixer provides linear operation The conversion loss is the rati
354. mode To Widen the System Bandwidth l Press Avg IF BW 2 Increase the IF bandwidth to increase the sweep speed The specifications and characteristics chapter of the reference guide shows the relative increase in sweep time as you decrease system bandwidth To Reduce the Averaging Factor By reducing the averaging factor number of sweeps or switching averaging off you can increasethe analyzer s measurement speed Thetime needed to compute averages can also slow the sweep time slightly in narrow spans l Press AVG FACTOR 2 Enter an averaging factor that is less than the value displayed on the analyzer screen and press x1 3 If you want to switch off averaging press AVERAGING OFF To Reduce the Number of Measurement Points 1 Press NUMBER OF POINTS 2 Enter a number of points that is less than the value displayed on the analyzer screen and press x1 Refer to the Specifications and Characteristics chapter of the reference guide for examples of how sweep time changes with the number of points To Set the Sweep Type Different sweep speeds are associated with the following three types of non power sweeps Choose the sweep type that is most appropriate for your application 1 Press SWEEP TYPE MENU 2 Select the sweep type Select LIN FREQ for the fastest sweep for a given number of fixed points Select LIST FREQ for the fastest sweep when specific non linearly spaced frequency points are of inter
355. mode allows the analyzer to phase lock to an external CW signal External source mode is best used for unknown signals or for signals that drift If a synthesized external source is used the tuned receiver mode is recommended because it is faster Primary Applications External source mode is useful in several applications when your test device is a mixer or other frequency translation device in automated test applications where a source is already connected to the system and you do not want to switch between the system source and the analyzer s internal source Typical Test Setup A typical test setup using the external source mode is shown in Figure 7 46 The same test setup is applicable for either manual or automatic external source mode operation 7 83 Operating Concepts Knowing the Instrument Modes Figure 7 46 Typical Setup for the External Source Mode NETWORK ANALYZER SYNTHES ZED SIGNAL GENERATOR POWER SPLITTER DUT pg6152d External Source Mode In Depth Description You may use the external source in automatic or manual mode External source mode phase locks the analyzer to an external CW signal NOTE The external source mode works only in CW time sweep External Source Auto f you press INSTRUMENT MODE EXT SOURCE AUTO theanalyzer turns on the external source auto mode You should observe the following poi
356. mpatible printer 4 9 l IF bandwidth reduction 7 35 Index IF bandwidth setting segment 7 18 IF delay detecting 5 10 IF detection 7 7 IF range measurement parameters 2 18 power meter calibration 2 18 receiver calibration 2 20 IF defining 2 7 imaginary format 7 29 improving measurement results decreasing the sweep rate 5 8 decreasing time delay 5 8 improving raw source match and load match for TRL LRM calibration 7 70 increase sweep speed using fast 2 port calibration 5 12 increasing dynamic range 5 14 increasingtest port input power 5 14 reducing receiver crosstalk 5 14 reducing thereceiver noisefloor 5 14 increasing measurement accuracy 5 4 connector repeatability 5 4 frequency drift 5 5 interconnecting cables 5 4 performance verification 5 5 reference plane and port extensions 5 5 temperature drift 5 5 increasing sweep speed 5 9 activating chop sweep mode 5 12 decreasing the frequency span 5 10 reducing the averaging factor 5 11 reducing the number of measurement points 5 11 setting the auto sweep time mode 5 11 setting the sweep type 5 11 using external calibration 5 12 using swept list mode 5 9 viewing a single measurement channel 5 12 wideningthesystem bandwidth 5 11 increasing test port input power 5 14 incrementing the source frequencies 2 29 in depth sequencing information 1 104 autostarting sequences 1 105 commands completed before next sequence b
357. mple and sweep correcti on mode using 6 36 sampler IF correction 7 7 Index 9 Index saving calibration data 6 5 7 65 data trace 1 19 instrument state 4 36 7 65 measurement results 4 37 measurement results graphically 4 45 modified calibration kits 7 65 to a disk 7 65 saving a file solving problems 4 53 saving and recalling instrument states 4 34 places where you can save 4 34 what you can savetoa computer 4 35 what you can save to a floppy disk 4 35 what you can save to the analyzer s internal memory 4 34 Saving measurement results ASCII data formats 4 40 instrument state files 4 46 scale and offset 7 9 scale choosing 4 15 searching for specific amplitude 1 39 segment menu 7 16 segment power setting 7 18 selecting auto feed 4 13 gate shape 3 36 line types 4 15 pen numbers and colors 4 14 selecting sweep modes 7 19 sending the exit HPGL mode and form feed sequence to the printer 4 24 sending the HPGL initialization sequence to the printer 4 24 sending the plot filetothe printer 4 24 sequence changing the title 1 102 dearing from memory 1 101 creating 1 97 decision making menu 1 111 editing 1 99 generating files in a loop counter example 1 115 in depth information 1 104 jumps to itself 1 111 limit test example 1 117 loading from a disk 1 103 loop counter example 1 114 naming files 1 102 Index 10 printing 1 104 purging from a disk 1 103 running 1 99
358. mponent can be attributed to the electrical length of the test device and represents the average signal transit time The higher order components are interpreted as variations in transit time for different frequencies and represent a source of signal distortion See Figure 7 15 Figure 7 15 Higher Order Phase Shift Frequency i Higher Order Phase Shift Component Phase Shift Component S Group Delay t r d in Radians do in Radians Sec do in Degrees 360 df f inHz o 2nf pb6115d The analyzer computes group delay from the phase slope Phase data is used to find the phase change A over a specified frequency aperture A f to obtain an approximation for the rate of change of phase with frequency Refer to Figure 7 16 This value 1 g represents the group delay in seconds assuming linear phase change over Af It is important that A 9 be lt 180 or errors will result in the group delay data These errors can be significant for long delay devices You can verify that A is lt 180 by increasing the number of points or narrowing the frequency span or both until the group delay data no longer changes 7 30 Operating Concepts Analyzer Display Formats Figure 7 16 Rate of Phase Change Versus Frequency Aperture fy f Frequency Phase E 4 92 pg6180 c When deviations from linear phase are present changing the frequency step can result in different values for group delay Note that
359. mputer for example COM 1 2 If using the COM 1 port output the filetothe plotter by using the following command C TYPE PLOTOO FP COMI 4 22 Printing Plotting and Saving Measurement Results Outputting Plot Files from a PC to an HPGL Compatible Printer Outputting Plot Files from a PC to an HPGL Compatible Printer To output the plot files toan HPGL compatible printer you can use the HPGL initialization sequence linked in a series as follows Step 1 Store the HPGL initialization sequence in a file named hpglinit Step 2 Store the exit HPGL mode and form feed sequence in a file named exithpgl Step 3 Send the HPGL initialization sequence tothe printer Step 4 Send the plot filetothe printer Step 5 Send the exit HPGL mode and form feed sequence to the printer Step 1 Store the HPGL initialization sequence 1 Create a test file by typing in each character as shown in the left column of Table 4 7 Do not insert spaces or linefeeds M ost editors allow the inclusion of escape sequences For example in the MS DOS editor DOS 5 0 or greater press CNTRL P hold down the CTRL key and press P followed by the E SCape key to create the escape character 2 Namethefile hpglinit Table 4 7 HPGL Initialization Commands Command Remark lt esc gt E conditional page eject lt esc gt amp 12A page size 8 5 x 11 lt esc gt amp 110 landscape orientation lower case 1 one capital o
360. n denotes a hazard It calls attention to a procedure that if not correctly performed or adhered to would result in damage to or destruction of the instrument Do not proceed beyond a caution sign until the indicated conditions are fully understood and met How to Use This Guide This guide uses the following conventions This represents a key physically located on the instrument SOFTKEY This represents a softkey a key whose label is determined by the instrument s firmware Screen Text This represents text displayed on the instrument s screen Documentation Map The Installation and Quick Start Guide provides procedures for installing configuring and verifying the operation of the analyzer It also will help you familiarize yourself with the basic operation of the analyzer TheUser s Guide shows how to make measurements explains commonly used features and tells you how to get the most performance from your analyzer The Reference Guide provides reference information such as specifications menu maps and key definitions The Programmer s Guide provides general GPIB programming information a command reference and example programs The Programmer s Guide contains a CD ROM with example programs The CD ROM provides the Installation and Quick Start Guide the User s Guide the Reference Guide and the Programmer s Guidein PDF format for viewing or printing from a PC The Service Guide provides informat
361. nalyzer can detect and download the calibration information from the internal memory of the ECal module 2 Press MODULE Ab sothat A is selected NOTE If you are calibrating with two modules the overlapping frequency span will be determined by the second module Therefore if you want to usethe calibration data of Module A in the overlapping frequency span calibrate using Module B first and then calibrate using Module A 3 Press the ECal calibration selection e The calibration choices are S111 PORT performs a measurement calibration for reflection onl y Measures of one port devices or properly terminated two port devices at port 1 of an S parameter test set 221 PORT performs a measurement calibration for reflection only Measures of one port devices or properly terminated two port devices at port 2 of an S parameter test set FULL 2 PORT performs a complete calibration for measurement of all four S parameters of a two port device This is the most accurate calibration for measurements of two port devices S11 S21 ENH RESP performs an S11 and S21 enhanced response calibration forward direction Enhanced response generates a 1 port cal for S11 and an improved calibration over the response cal for S21 S22 S12 ENH RESP performs an S22 and S12 enhanced response calibration reverse direction Enhanced response generates a 1 port cal for S22 and an improved calibration over the response cal for S12 Once
362. ncouple channels 1 and 2 for this measurement using the COUPLED CHAN ON off softkey set to OFF to allow alternating sweeps After uncoupling channels 1 and 2 you may want to change the fundamental power and see the resultant change in relative harmonic power in dBc COUPLE PWR ON off allows you to change the power of both channels simultaneously even though they are uncoupled in all other respects Frequency Range The frequency range is determined by the upper frequency range of the instrument or system 3 or 6 GHz and by the harmonic being displayed The 6 GHz operation requires an 8753ET ES Option 002 and Option 011 with Option 006 Table 7 4 shows the highest fundamental frequency for maximum frequency and harmonic mode Table 7 4 Maximum Fundamental Frequency using the Harmonic Mode Harmonic Maximum Fundamental Frequency Measured 8753ES Option 011 8753ES Option 011 with with Option 002 Option 002 and Option 006 2nd Harmonic 1 5 GHz 3 0 GHz 3rd Harmonic 1 0 GHz 2 0 GHz Accuracy and Input Power Refer to the specifications and characteristics chapter of the reference guide for recommendations on the maximum input power and maximum source power Using power levels greater than the recommended values may cause undesired harmonics in the source and receiver The recommended power levels ensure that these harmonics are less than 45 dBc Use test port power to limit the input power to your test device
363. ncy range over which a particular standard is valid can be defined with a minimum and maximum frequency This is particularly important for a wavegui de standard since the minimum frequency is used to define the waveguide cutoff frequency Note that several band limited standards can together be defined as the same class see Specify Class Menu on page 7 62 Then if a measurement calibration is performed over a frequency range exceeding a single standard additional standards can be used for each portion of the range 7 60 Operating Concepts Modifying Calibration Kits Lastly the standard must be defined as either coaxial or waveguide If it is waveguide dispersion effects are calculated automatically and induded in the standard model Thefollowing is a description of the softkeys located within the specify offset menu OFFSET DELAY allows you to specify the one way electrical delay from the measurement reference plane to the standard in seconds s In a transmission standard offset delay is the delay from planeto plane Delay can be calculated from the precise physical length of the offset the permittivity constant of the medium and the speed of light In coax group delay is considered constant In waveguide however group delay is dispersive that is it changes significantly as a function of frequency H ence for a waveguide standard offset delay must be defined as though it were a TEM wave without dispersion
364. nd of a bandpass filter where the center frequency of the filter is approximately 1 8 GHz and has a bandwidth of approximately 2 9 GHz Refer to Figure 1 62 Figure 1 62 Bandpass Filter Being Ripple Tested i Jun 2888 14 82 54 Hi 11 Log 5 dB REF 13 dB 1 1 8458 dB 1 812 384 969 GHZ 1 812984B69 GHz START 859 000 00G GHz STOP 5 888 668 aga GHz pa5196e 1 80 Making Measurements Using Ripple Limits to Test a Device Setting Up the Analyzer to Perform the Ripple Test This section sets up the analyzer so that a bandpass filter can be easily viewed on the analyzer display 1 Connect your filter as shown in Figure 1 63 Figure 1 63 Connections for an Example Ripple Test Measurement NETWORK ANALYZER pa53e 2 Press and choose the measurement settings For this example the measurement settings are as follows Trans FWD S21 B R e Scale Ref AUTO SCALE You may also want to select settings for the number of data points power averaging and IF bandwidth 3 Substitute a thru for the device and perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU 4 Reconnect your test device 5 To better view the measurement trace press Scale Ref AUTO SCALE Refer to Figure 1 64 1 81 Making Measurements Using Ripple Limits to Test a Device Figure 1 64 Filter Pass Band Before Ripple Tes
365. ndwidth 4 To select a response correction press CALIBRATE MENU RESPONSE 5 Makea thru connection between the points where you will connect your DUT NOTE Include any adapters or cables that you will havein the device measurement That is connect the standard device where you will connect your DUT Figure 6 3 Standard Connections for Response Error Correction for Transmission Measurements NETWORK ANALYZER Test Port Cables Possible Adapters pa579e 6 14 Calibrating for Increased Measurement Accuracy Frequency Response Error Corrections 6 To measure the standard press THRU The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the THRU softkey after it measures the calibration standard and computes the error coefficients NOTE Do not use an open or short standard for a transmission response correction NOTE You can save or store the measurement correction to use for later measurements Refer to the Chapter 4 Printing Plotting and Saving Measurement Results for procedures 7 This completes the response correction for transmission measurements You can connect and measure your device under test Receiver Calibration Receiver calibration provides a frequency response error correction for a non ratioed measurement that also indicates absolute power in dBm This calibration is most useful when performed with a power meter calibr
366. ng and Saving Measurement Results for procedures 18 This completes the full two port correction procedure You can connect and measure your device under test 6 32 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration Power Meter Measurement Calibration A GPIB compatible power meter can monitor and correct RF source power to achieve leveled power at the test port During a power meter calibration the power meter samples the power at each measurement point across the frequency band of interest The analyzer then constructs a correction data table to correct the power output of the internal source The correction table may be saved in an instrument state register with the SAVE key The correction table may be updated on each sweep in a leveling application or during an initial single sweep In the sample and sweep mode the power meter is not needed for subsequent sweeps The correction table may be read or modified through GPIB Power meter calibration is useful for the following applications when you aretesting a system with significant frequency response errors for example a coupler with significant roll off or a long cable with a significant amount of loss when you are measuring devices that are very sensitive to actual input power for proper operati on when you require a reference for receiver power calibration The power meter can measure and correct power in two ways continuous
367. ng ADAPTER DELAY and entering the value 7 Select the appropriate key ADAPTER COAX 0r ADAPTER WAVEGUIDE 8 Press REMOVE ADAPTER to complete the technique for calculating the new error coefficients and overwrite the current active calibration set in use This process uses up an internal memory register The calibration in this register is not the calibration created by adapter removal rather it is a scratch calibration You may wish to delete the register or re save the new calibration in this register as shown in the following step 9 Tosave the results of the new calibration set press Save Recall SELECT DISK INTERNAL MEMORY RETURN SAVE STATE NOTE Adapter removal can leave a residual state in internal memory This is not a valid instrument state and should be deleted 6 76 Calibrating for Increased Measurement Accuracy Adapter Removal Using ECal 10 Connect the DUT to the network analyzer as shown in Figure 6 30 to perform calibrated measurements Figure 6 30 Calibrated Measurement NETWORK ANALYZER Reference Reference Port 1 Port 2 pa5101e Verify the Results Since the effect of the adapter has been removed it is easy to verify the accuracy of the technique by simply measuring the adapter itself Because the adapter was used during the creation of the two calibration sets and the technique removes its effects measurement of the adapter itself should show the S parameters If unexpected phase variations
368. ng Parameters to Default Values 1 Press Copy DEFINE PRINT DEFAULT PRNT SETUP Table 4 1 Default Values for Printing Parameters Printing Parameter Default Printer Mode M onochrome Auto Feed ON Printer Colors Channel 1 and 3 Data Magenta Channel 1 and 3 Memory Green Channel 2 and 4 Data Blue Channel 2 and 4 Memory Red Graticule Cyan Warning Black Text Black Ref Line Black Printing One Measurement Per Page 1 Configure and define the print function as explained in Configuring a Print Function on page 4 4 and Defining a Print Function on page 4 6 2 Press Copy PRINT MONOCHROME If you defined the AUTO FEED OFF press PRINTER FORM FEED after the message COPY OUTPUT COMPL BT ED appears Printing Plotting and Saving Measurement Results Printing Multiple Measurements Per Page Printing Multiple Measurements Per Page 1 Configure and define the print function as explained in Configuring a Print Function on page 4 4 and Defining a Print Function on page 4 6 2 Press Copy DEFINE PRINT and then press AUTO FEED until the softkey label appears as AUTO FEED OFF 3 Press RETURN PRINT MONOCHROME to print a measurement on the first half page 4 Makethe next measurement that you want to see on your hardcopy Figure 4 2 shows an example of a hardcopy where two measurements appear 5 Press PRINT MONOCHROME to print a measurement on the second half page NOTE T
369. ng is the y axis value In polar or Smith chart format with a magnitude phase marker a real imaginary marker an RX marker or a G B marker the setting applies to the first part of the complex data pair Fixed marker response values are always uncoupled in the two channels Toset the auxiliary response value of a fixed marker when you are viewing a polar or Smith format press FIXED MKR AUX VALUE and turn the front panel knob or enter a value from the front panel keypad This valueis the second part of complex data pair and applies to a magnitude phase marker a real imaginary marker an RX marker or a G4jB marker Fixed marker auxiliary response values are always uncoupled in the two channels 1 30 Making Measurements Using Markers Figure 1 18 Example of a Fixed Reference Marker Using REF XA FIXED MKR CH1 Sa log MAG 10 dB REF 50 dB 2 16 415 dB 9 968 881 MHz REF 4 TIMULUS OF PSET CENTER 134 000 MHz SPRN 36 8000 06 MHz aw000033 To Couple and Uncouple Display Markers At a preset state the markers have the same stimulus values on each channel but they can be uncoupled so that each channel has independent markers Press MARKER MODE MENU and select from the following keys e Choose MARKERS COUPLED if you want the analyzer to couple the marker stimulus values for the display channels Choose MARKERS UNCOUPLED if you want the analyzer
370. ng plotting parameters to default values 4 16 selecting auto feed 4 13 selecting line types 4 15 selecting pen numbers and colors 4 14 plot speed choosing 4 16 plotting measurement results 4 3 measurement to a disk 4 11 measurements in page quadrants 4 28 multiple measurements on a full page 4 27 multiple measurements per page from a disk 4 26 multiple measurements per page using a pen plotter 4 18 one measurements per page using a pen plotter 4 17 parameters resetting to default values 4 16 plotting to an HPGL compatible printer 4 19 solving problems 4 33 plotting a measurement to a disk to output the plot files 4 12 polar format 7 27 polar format markers 1 32 port extensions 5 5 power coupling options 7 10 channel coupling 7 10 test port coupling 7 10 power meter calibration 2 10 calibration over IF range 2 18 calibration over RF range 2 21 power meter measurement calibration 6 33 calibratingtheanalyzer receiver to measure absolute power 6 39 compensating for directional coupler response 6 35 entering the power sensor calibration data 6 34 interpolation in power meter calibration 6 34 loss of power meter calibration data 6 33 using continuous correction mode 6 38 using sample and sweep correction mode 6 36 power sensor calibration data entering 6 34 power sweep 7 19 power output 7 10 primary measurement channels viewing 1 12 principles group delay
371. ng the List Values or Operating Parameters Printing or Plotting the List Values or Operating Parameters Press LIST and select the information that you want to appear on your hardcopy Choose LIST VALUES if you want a tabular listing of the measured data points and their current values to appear on your hardcopy This list will also include the limit test information if you have the limits function activated Choose OP PARMS MKRS etc if you want a tabular listing of the parameters for both measurement channels to appear on your hardcopy The parameters include operating parameters marker parameters and system parameters that relate to the control of peripheral devices If You Want a Single Page of Values 1 Choose PRINT MONOCHROME for a printer or PLOT for a plotter peripheral to create a hardcopy of the displayed page of listed values 2 Press NEXT PAGE todisplay the next page of listed values Press PREVIOUS PAGE to display the previous page of listed values Or you can press NEXT PAGE or PREVIOUS PAGE repeatedly to display a particular page of listed values that you want to appear on your hardcopy Then repeat the previous step to create the hardcopy 3 Repeat the previous two steps until you have created hardcopies for all the desired pages of listed values If you are printing the list of measurement data points each page contains 30 lines of data The number of pages is determined by the number of measurement poi
372. nment such as a transistor test fixture or microstrip Microstrip devices in the form of chips MMIC s packaged transistors or beam lead diodes cannot be connected directly to the coaxial ports of the analyzer The device under test DUT must be physically connected to the network analyzer by some kind of transition network or fixture Calibration for a fixtured measurement in microstrip presents additional difficulties A calibration at the coaxial ports of the network analyzer removes the effects of the network analyzer and any cables or adapters before the fixture however the effects of the fixture itself are not accounted for An in fixture calibration is preferable but high quality short open load thru SOLT standards may not be readily available to allow a conventional full 2 port calibration of the system at the desired measurement plane of the device In microstrip a short circuit is inductive an open circuit radiates energy and a high quality purely resistive load is difficult to produce over a broad frequency range The Thru Reflect Line TRL 2 port calibration is an alternativeto the traditional SOLT Full 2 port calibration technique that utilizes simpler more convenient standards for device measurements in the microstrip environment For coaxial waveguide and other environments where high quality impedance standards are readily available the traditional short open load thru SOLT method provides the most accurate results s
373. nnel channel 4 7 Press Chan 3 Observe that the amber LED adjacent to the key is lit This indicates that channel 3 is now active and can be configured 8 Rotate the front panel control knob and notice that marker 2 still moves on all four channel traces Making Measurements Using Display Functions 9 Toindependently control the channel markers Press MARKER MODE MENU set MARKERS toUNCOUPLED Rotate the front panel control knob Marker 2 moves only on the channel 3 trace Once made active a channel can be configured independently of the other channels in most variables except sti mulus For example once channel 3 is active you can change its format to a Smith chart by pressing SMITH CHART Customizing the Four Channel Display When one or both auxiliary channels are enabled DUAL CHAN on OFF and SPLIT DISP 1X 2X 4X interact to produce different display configurations according to Table 1 1 Table 1 1 Customizing the Display Split Display Dual Channel Aux Channels On Number of Graticules 1X Don t Care Don t Care 1 1X 2X 4X Off None 2X 4X Off 3or4 2 2X On Don t Care 4X On 3or4 3 4X On Both on 4 Channel Position Softkey CHANNEL POSITION gives you options for arranging the display of the channels Press CDisplay DUAL QUAD SETUP touse CHANNEL POSITION CHANNEL POSITION works with SPLIT DISP 1X 2X 4X When SPLIT DISP 2X is selected CHANNEL POSITION gives yo
374. non ratioed measurement press INPUT PORTS B Press TEST PORTS 1 This sets the source at PORT 1 4 Set any other measurement parameters that you want for the device measurement power number of points IF bandwidth 5 To perform a receiver error correction press CALIBRATE MENU RECEIVER CAL TAKE RCVR CAL SWEEP NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures 6 This completes the receiver calibration for transmission measurements You can connect and measure your device under test NOTE The accuracy of the receiver calibration will be nearly the same as the test port power accuracy and the test port power accuracy can be significantly improved by performing a power meter source calibration as described later in Power Meter Measurement Calibration on page 6 33 Calibrations at powers other than 0 dBm are possible Receiver calibration normalizes the traceto the value set for the reference level For example to do a receiver calibration at 10 dBm set the source to 10 dBm set the reference level to 10 dBm then perform the receiver calibration 6 16 Calibrating for Increased Measurement Accuracy Frequency Response and Isolation Error Corrections Frequency Response and Isolation Error Corrections You can make a response and isolation correction for the following measurements e reflection
375. ns requirements 8 8 gosub sequence command 1 106 GPIB operation address menu 7 79 GPIB STATUS indicators 7 78 local key 7 77 pass control mode 7 78 system controller mode 7 78 talker listener mode 7 78 using the parallel port 7 79 GPIO mode 1 106 7 80 graphic files saving measurement results as 4 45 grids moving marker information off the grids 1 26 group delay 1 46 group delay format 7 25 group delay measurements 2 32 group delay principles 7 29 H harmonic measurements additional 1 56 making 1 55 harmonic operation 7 87 accuracy 1 58 accuracy and input power 7 88 coupling power between channels 1 and 2 1 58 7 88 dual channel operation 1 57 7 87 frequency range 1 58 7 88 input power 1 58 single channel operation 1 57 7 87 test setup typical 7 87 understanding 1 57 harmonics measuring 1 54 high dynamic range measurement 2 22 swept RF IF conversion loss 2 18 high dynamic range measurement 2 22 high dynamic range swept RF IF conversion loss measurement parameters for F range 2 18 power meter calibration over IF range 2 18 power meter calibration over RF range 2 21 receiver calibration over IF range 2 20 RF frequency range 2 21 horizontal axis 3 13 3 14 3 16 3 20 3 23 how RF and IF are defined 2 7 HPGL compatible printer 4 19 initialization sequence sending tothe printer 4 24 initialization sequence storing 4 23 HPGL compatible printer 4 23 HPGL 2 co
376. nses can be to each other and still be distinguished from each other For responses of equal amplitude the response resolution is equal to the 5096 6 dB impulse width It is inversely proportional to the measurement frequency span and is also a function of the window used in the transform The approximate formulas for calculating the 5096 impulse width are given in Table 3 3 For example using the formula for the bandpass mode with a normal windowing function for a 50MHzto 13 05 GHz measurement 13 0 GHz span 0 98 _ 2 50 percent calculated impulse width 130 GH3 x 0 151 nanoseconds Electrical length in air 0 151 x 10 s 30 x 10 m s 4 53 centimeters With this measurement two equal responses can be distinguished when they are separated by at least 4 53 centimeters In a measurement with a 20 GHz span two equal responses can be distinguished when they are separated by at least 2 94 cm U sing the low pass mode the low pass frequencies are slightly different with a minimum windowing function you can distinguish two equal responses that are about 1 38 centimeters or more apart For reflection measurements which measure the two way time to the response divide the response resolution by 2 U sing this example you can distinguish two faults of equal magnitude provided they are 0 69 centi meters electrical length or more apart NOTE Remember to determine the physical length the relative velocity factor of
377. nsmission return port is never exactly the characteristic impedance some of the transmitted signal is reflected from the test set port 2 and from other mismatches between the test device output and the receiver input to return tothe test device A portion of this signal may be re reflected at port 2 thus affecting S51 or part may be transmitted through the device in the reverse direction to appear at port 1 thus affecting Siim This error term which causes the magnitude and phase of the transmitted signal to vary as a function of S254 is called load match E p See Figure 7 36 7 47 Operating Concepts Measurement Calibration Figure 7 36 Load Match E f PORT PORT 2 ee zs I en S l 21 0e m e 7 Sai EsF Ys As VEL wt Me LOAD SOURCE MATCH MATCH a ERF S42 pg661d The measured value S21m consists of signal components that vary as a function of the relationship between E sp and 5144 as well as E p and S754 sothe input and output reflection coefficients of the test device must be measured and stored for use in the S214 error correction computation Thus thetest setup is calibrated as described for reflection to establish the directivity Epp source match Esp and reflection frequency response Err terms for reflection measurements on both ports Now that a calibrated port is available for reflection measurements the thru is connected and load match E p is determ
378. nstruction contact your local Agilent Technologies Sales and Service Office about course numbers HP Agilent 85050A 424A and 85050A 424D See the following table for quick reference tips about connector care Table 5 1 Connector Care Quick Reference Handling and Storage Do K eep connectors clean DoNot Touch mating plane surfaces Extend sleeve or connector nut Set connectors contact end down Use plastic end caps during storage Visual Inspection Do Inspect all connectors carefully DoNot Usea damaged connector ever Look for metal particles scratches and dents Connector Cleaning Do Try compressed air first DoNot Useany abrasives Use isopropyl alcohol Get liquid into plastic support beads Clean connector threads Gaging Connectors Do Clean and zero the gage before use Do Not Usean out of spec connector Usethe correct gage type Use correct end of calibration block Gage all connectors before first use Making Connections Do Align connectors carefully DoNot Apply bending force to connection Make preliminary connection lightly Over tighten preliminary connection Turn only the connector nut Twist or screw any connection Use a torque wrench for final connect Tighten past torque wrench break point 5 3 Optimizing Measurement Results Increasing Measurement Accuracy Increasing Measurement Accuracy The following all contribute to loss of accuracy in a measurement Interconn
379. nterpreting the Forward Transform Horizontal Axis In a frequency domain transform of a CW time measurement the horizontal axis is measured in units of frequency The center frequency is the offset of the CW frequency For example with a center frequency of 0 Hz the CW frequency 250 MHz in the example is in the center of the display If the center frequency entered is a positive value the CW frequency shifts to the right half of the display a negative value shifts it to theleft half of the display The span value entered with the transform on is the total frequency span shown on the display Alternatively the frequency display values can be entered as start and stop Demodulating the Results of the Forward Transform The forward transform can separate the effects of the CW frequency modulation amplitude and phase components For example if a test device modulates the transmission response S21 with a 500 Hz AM signal you can see the effects of that modulation as shown in Figure 3 18 To simulate this effect apply a 500 Hz sine wave to the analyzer rear panel EXT AM input Figure 3 18 Combined Effects of Amplitude and Phase Modulation CH1 B log MAG 10 dB AEF 50 GB i 20 809 dB tal Oo Hz y CH1 CENTEA O Hz Cw 250 000 000 MHz SPAN 2 kHz pg6187 c Using the demodulation capabilities of the analyzer it is possibleto view the amplitude or the phase component of
380. nts that you have selected If You Want the Entire List of Values Choose PRINT ALL to print all pages of the listed values NOTE If you are printing the list of operating parameters only the first four pages are printed The fifth page system parameters is printed by displaying that page and then pressing PRINT 4 32 Printing Plotting and Saving Measurement Results Solving Problems with Printing or Plotting Solving Problems with Printing or Plotting f you encounter a problem when you are printing or plotting check the following list for possible causes Look in the analyzer display message area The analyzer may show a message that will identify the problem Refer to the Error Messages chapter of the reference guide if a message appears If necessary refer to the peripheral configuration procedures in this chapter to check that you have done the following L connected an interface cable between the peripheral and the analyzer L connected the peripheral to ac power T switched on the power 1 switched the peripheral on line m selected the correct printer or plotter type If you are using a laser printer for plotting and the printer is outputting partial plots the printer may require more memory or the page protection activated NOTE Consult your printer documentation for information on upgrading memory and how to activate page protection Make sure that the analyzer address setting for the peripheral
381. nts when using this operation mode Theauto mode has a wider capture range than the manual mode Themanual mode is faster than the auto mode Theauto mode searches for the incoming CW signal Thecapture range is typically 1096 of the selected CW frequency This feature works only in CW time sweep type Theincoming signal should not have large spurs or sidebands as the analyzer may phase lock on a spur or not phase lock at all The frequency the instrument has locked onto is shown on the analyzer and is also available via GPIB External Source Manual f you press INSTRUMENT MODE EXT SOURCE MANUAL the analyzer activates the external source manual mode You should observe the following points when using this operation mode Themanual mode has a smaller capture range than the auto mode Themanual mode is much faster than auto mode This feature works only in CW time sweep type 7 84 Operating Concepts Knowing the Instrument Modes Theincoming signal should not have large spurs or sidebands as the analyzer may phase lock on a spur or not phase lock at all e The frequency of the incoming signal should be within 0 5 to 45 0 MHz of the selected frequency or the analyzer will not be ableto phaselock to it CW Frequency Range in External Source Mode 300kHzto3 GHz 6 GHz for Option 006 Compatible Sweep Types The external source mode will only function in CW time sweep If the instrument is in any other sweep
382. nu previously described It allows definition of a label up to eight characters long After a new calibration kit has been defined be sureto specify a label for it Choose a label that describes the connector type of the calibration devices This label will then appear in the CAL KIT softkey label in the correction menu and the MODIFY label in the select cal kit menu It will be saved with calibration sets Verify Performance Once a measurement calibration has been generated with a user defined calibration kit its performance should be checked before making device measurements To check the accuracy that can be obtained using the new calibration kit a device with a well defined frequency response preferably unlike any of the standards used should be measured The verification device must not be one of the calibration standards measurement of one of these standards is merely a measure of repeatability To achieve more complete verification of a particular measurement calibration accurately known verification standards with a diverse magnitude and phase response should be used National standard traceable or Agilent standards are recommended to achieve verifiable measurement accuracy NOTE The published specifications for this network analyzer system include accuracy enhancement with compatible calibration kits Measurement calibrations made with user defined or modified calibration kits are not subject to the analyzer specifications
383. o control the data exchange by transmitting control characters to the network analyzer LY If you choose DTR DSR the handshake method allows the printer to control the data exchange by setting the electrical voltage on one line of the RS 232 serial cable Becausethe DTR DSR handshaketakes place in the hardware rather than the firmware or software it is the fastest transmission control method 4 Press Local SET ADDRESSES PLOTTER PORT andthen PLTR TYPE until PLTR TYPE HPGL PRT appears If You Are Plotting to a Pen Plotter 1 Press Local SET ADDRESSES PLOTTER PORT andthen PLTR TYPE until PLTR TYPE PLOTTER appears 2 Configurethe analyzer for one of the following plotter interfaces 4 10 Choose PLTR PORT GPIB if your plotter has a GPIB interface and then configure the plot function as follows a Enter the GPIB address of the plotter default is 05 followed by x1 b Press and SYSTEM CONTROLLER if thereis no external controller connected to the GPIB bus c Press and USE PASS CONTROL ifthereis an external controller connected to the GPIB bus Printing Plotting and Saving Measurement Results Configuring a Plot Function Choose PARALLEL if your plotter has a parallel Centronics interface and then configure the plot function as follows T Press and then select the parallel port interface function by pressing PARALLEL until the correct function appears f you choose PARALLEL COPY the parallel
384. o of thelF output level to the RF input level This value remains constant over a specified input power range When the input power level exceeds a certain maximum the constant ratio between IF and RF power levels will begin to change The point at which the ratio has decreased by 1 dB is called the 1 dB compression point See Figure 2 27 Figure 2 27 Conversion Loss and Output Power as a Function of Input Power Level Example b edd e comprsssonront_ E EHE LI LT Power dBm IF Conversion T Ratio ip EN ET IIIA Input Signal Power RF Input Signal Power RF pa5158e Notice that the IF output power increases linearly with the increasing RF signal until mixer compression begins and the mixer saturates The following example uses a ratio of mixer output to input power and a marker search function to locate a mixer s 1 dB compression point 1 Set the LO source to the desired CW frequency of 600 MHz and power level to 13 dBm 2 Initialize the analyzer by pressing Preset 3 Set theanalyzers LO frequency to match the frequency of the LO source by pressing SWEEP TYPE MENU POWER SWEEP INSTRUMENT MODE FREQ OFFS MENU LO MENU FREQUENCY CW 4 Toset the analyzer to the desired power sweep range press 2 37 Making Mixer Measurements Conversion Compression Using the Frequency Offset Mode 5 Makethe connections as shown in Figure 2 28 CAUTION To prevent connector damage use an adapter part numb
385. oftware it is the fastest transmission control method Printing Plotting and Saving Measurement Results Defining a Print Function Defining a Print Function NOTE The print definition is set to default values whenever the power is cycled However you can save the print definition by saving the instrument state 1 Press Copy DEFINE PRINT 2 Press PRINT MONOCHROME or PRINT COLOR m Choose PRINT MONOCHROME if you are using a black and white printer or you want just black and white from a color printer LY Choose PRINT COLOR if you are using a color printer 3 Press AUTO FEED until the correct choice ON or OFF is highlighted m Choose AUTO FEED ON if you want to print one measurement per page m Choose AUTO FEED OFF if you want to print multiple measurements per page NOTE Laser printers and some Desk et printers do not begin to print until a full page or a partial page and a form feed have been received If You Are Using a Color Printer l Press PRINT COLORS 2 If you want to modify the print colors select the print element and then choose an available color NOTE You can set all the print elements to black to create a hardcopy in black and white Since the media color is usually white or clear you could set a print element to white if you do not want that element to appear on your hardcopy Printing Plotting and Saving Measurement Results Printing One Measurement Per Page To Reset the Printi
386. olving problems 4 53 recalling instrument states 4 34 receiver calibration 6 15 crosstalk reducing 5 14 5 16 noise floor reducing 5 14 receiver block 7 4 reducing averaging factor 5 11 effect of spurious responses 2 5 number of measurement points 5 11 reducing recall time 5 17 understanding spur avoidance 5 17 reducing trace noise 5 15 activating averaging 5 15 changing system bandwidth 5 15 reduction IF bandwidth 7 35 reference plane and port extensions 5 5 reflection measurements response and isolation error correction 6 19 response error correction 6 12 reflection measurements in time domain low pass 3 16 interpreting the low pass response horizontal axis 3 16 interpreting the low pass response vertical axis 3 17 reflection measurements using bandpass interpreting the band pass reflection response vertical axis 3 13 reflection measurements using bandpass mode 3 12 interpreting the bandpass reflection response horizontal axis 3 13 reflection response measurements making 3 9 relative velocity factor adjusting 3 12 removing adapter delay 6 42 removing the effect of an adapter 6 76 renaming a file 4 52 repeatability connector 5 4 repetitive switching of the attenuator 7 13 required peripheral equipment 7 5 required test equipment connecting 1 4 requirements for TRL standards 7 71 re saving an instrument state 4 51 resetting plotting parameters to default values 4 16
387. omatically by the analyzer whenever a plot is requested The two digit sequence number is incremented by one each time a file with a default name is added to the directory Figure 4 9 Plot Filename Convention i dg ine S PART OF A MULTIPLE FILE PLOT ON THE OPTIONAL CHARACTER THAT INDICATES THE FILE USER GENERATED SAME GRATICULE OUTPUT FORMAT CODE THAT INDICATES THE PLOT QUADRANT POSITION OR FULL PAGE FP FULL PAGE DEFAULT LU LEFT UPPER QUADRANT AUTO GENERATED LL LEFT LOWER QUADRANT RU RIGHT UPPER QUADRANT RL RIGHT LOWER QUADRANT PLOT FILES SEQUENCE NUMBER Ud TO 31 ROOT OF FILENAME ph646c 4 26 Printing Plotting and Saving Measurement Results Plotting Multiple Measurements Per Page from Disk To Plot Multiple Measurements on a Full Page You may want to plot various files to the same page for example to show measurement data traces for different input settings or parameters on the same graticule 1 2 Define the plot as explained in Defining a Plot Function on page 4 13 Press PLOT DEFINE PRINT The analyzer assigns thefirst available default filename for the displayed directory For example the analyzer would assign PLOTOOFP if there were no previous plot files on the disk Press and turn the front panel knob to highlight the name of the file that you just saved Press FILE UTILITIES RENAME FILE and turn the front panel knob to plac
388. on Perform a Receiver Calibration Over the IF Range 1 Connect the measurement equipment as shown in Figure 2 17 Figure 2 17 Connections for Receiver Calibration NETWORK ANALYZER 1000 MHz Low Pass Filter 10 dB pa539e 2 Tocalibratethe B channel over thelF range press B CALIBRATE MENU RECEIVER CAL TAKE RCVR CAL SWEEP Once completed the analyzer should display 5 dBm 2 20 Making Mixer Measurements High Dynamic Range Swept RF IF Conversion Loss Set the Analyzer to the RF Frequency Range You can find the RF frequency range by using a simple calculation or using the mixer measurement diagram on the analyzer display Using the Calculation Add the LO frequency to the IF frequency start and stop values If using an LO frequency of 1500 MHz the RF start frequency would be 1 6 GHz 1500 100 MHz and the stop frequency would be 2 5 GHz 1500 1000 M Hz Using the Mixer Measurement Diagram While the analyzer is still set tothe IF frequency range press INSTRUMENT MODE FREQ OFFS MENU LOMENU FREQUENCY CW RETURN RETURN DOWN CONVERTER RF gt LO Notethe RF frequency values on the diagram Press Start 1 6 Gin Stop 2 5 Gin Perform a Power Meter Calibration Over the RF Range 1 Connect the equipment as shown in Figure 2 18 Figure 2 18 Connections for Power Meter Calibration NETWORK ANALYZER 1000 MHz Low Pass Filter GPIB pa536e 2 Usethe previous power meter settings 2
389. on phase nears zero or is an integer multiple of 180 degrees and this condition is not recommended For a transmission media that exhibits linear phase over the frequency range of interest the following expression can be used to determine a suitable line length of one quarter wavelength at the center frequency which equals the sum of the start frequency and stop frequency divided by 2 Electrical length cm LINE Q length THRU 15000x yF Electrical length cm fI MHz f2 MHz let f1 1000 MHz f2 2000 MHz VF Velocity Factor 1 for this example Thus the length to initially check is 5 cm Next use the following to verify the insertion phase at f1 and f2 _ 860x fx I Phase degrees where f frequency length of line v velocity speed of light x velocity factor which can be reduced to the following using frequencies in MHz and length in centimeters _ 0 012 x MHz x l cm Phase degrees approx MUT 7 73 Operating Concepts TRL LRM Calibration So for an air line velocity factor approximately 1 at 1000 MHz the insertion phase is 60 degrees for a 5 cm line it is 120 degrees at 2000 MHz This line would be a suitable line standard For microstrip and other fabricated standards the velocity factor is significant In those cases the phase calculation must be divided by that factor For example if the dielectric constant for a substrate is 10 and the corresponding effective die
390. on should have as low a reflection coefficient as the load used to determine directivity The additional reflection error caused by an improper termination at the test device s output port is not incorporated into the one port error model Two Port Error Model The error model for measurement of the transmission coefficients magnitude and phase of a two port deviceis derived in a similar manner The potential sources of error are frequency response tracking source match load match and isolation as shown in Figure 7 34 These errors are effectively removed using the full two port error model 7 46 Operating Concepts Measurement Calibration Figure 7 34 Major Sources of Error MEASUREMENT ERRORS Tracking S21M 2 Measured Value Source Match 9 Isolation e Directivity Unknown pg659d The transmission coefficient is measured by taking the ratio of the incident signal I and the transmitted signal T Refer to Figure 7 35 Ideally 1 consists only of power delivered by the source and T consists only of power emerging at the test device output Figure 7 35 Transmission Coefficient I T E Forward S21M 67v 7 t 521A ETF EE T S D Reverse 512M 51 24 d e 5124 Ege 312A ETR pg660d As in the reflection model source match can cause the incident signal to vary as a function of test device S414 Also since the test setup tra
391. oncepts Calibration Routines Calibration Routines There aretwelve different error terms for a two port measurement that can be corrected by accuracy enhancement in the analyzer These are directivity source match load match isolation reflection tracking and transmission tracking each in both the forward and reverse direction The analyzer has several different measurement calibration routines to characterize one or more of the systematic error terms and remove their effects from the measured data The calibrate menu allows you to perform the measurement calibration routines These procedures range from a simple frequency response calibration to a full two port calibration that effectively removes all twelve error terms Response Calibration The response calibration activated by pressing the RESPONSE softkey within the calibrate menu provides a normalization of the test setup for reflection or transmission measurements This calibration procedure may be adequate for measurement of well matched devices This is the simplest error correcti on to perform and should be used when extreme measurement accuracy is not required Response and Isolation Calibration The response and isolation calibration activated by pressing the RESPONSE amp ISOL N softkey within the calibrate menu provides a normalization for frequency response and crosstalk errors in transmission measurements or frequency response and directivity errors in reflection
392. ond Selection of the appropriate sweep time depends on the device being measured the longer the electrical delay of the device under test the slower the sweep rate must be A good way totell when the sweep rate is slow enough is to put the vector network analyzer into a stepped list frequency mode of sweeping and compare the data In this mode the vector network analyzer does not sweep the frequency but steps to each listed frequency point stops makes a measurement then goes on tothe next point Because errors do not occur in the list frequency mode it can be used to check the data The disadvantage of the list frequency mode is that it is slower than sweeping To select the stepped list mode instead of the swept list mode press SWEEP TYPE MENU EDIT LIST andtoggle LIST TYPE to LIST TYPE STEPPED Alternatively the analyzer can be forced into stepped sweep mode by SettingthelF bandwidth to either 30 Hz or 10 Hz e Setting sweep time to greater than 15 ms point Activating power meter calibration even with no calibration PWRMTR CAL ONE SWEEP Decreasing the Time Delay The other way to reduce AF is by decreasing the time delay AT Since AT is a property of the device that is being measured it cannot literally be decreased H owever what can be decreased is the difference in delay times between the paths to the R channel and the B channel These times can be equalized by adding a length of cable tothe R channel which has
393. onics higher frequency spectral noise and line related noise Sweep to sweep averaging however is better at filtering out very low frequency noise A tenfold reduction in IF bandwidth lowers the measurement noise floor by about 10 dB Bandwidths less than 300 Hz provide better harmonic rejection than higher bandwidths Another difference between sweep to sweep averaging and variablelF bandwidth is the sweep time Averaging displays the first complete trace faster but takes several sweeps to reach a fully averaged trace IF bandwidth reduction lowers the noise floor in one sweep but the sweep time may be slower The difference in noise floor between a trace measured with a 3000 HzIF bandwidth and with a 10 Hz IF bandwidth is illustrated by Figure 7 20 7 35 Operating Concepts Noise Reduction Techniques Figure 7 20 IF Bandwidth Reduction 41 S21 log MAG 10 dB REF 10 dB AVERAGING CH S21 log MAG 10 See REF 10 dB AVERAGING RESTART f T RESTART i Jl AVERAGING 1 AVERAGING or FACTOR Cor FACTOR IF ANDVIUTM AVERAGING AVERAGING on OFF on OFF SMOOTHING SMOOTHING APERTURE APERTURE ni m AM sMootHinc SMOOTHING I aM on OFF on OFF IF BW IF ew t3000 Hz t10 Hx CENTER 167 558 000 MHz SPAN 300 GOO MHz CENTER 157 558 000 MHz SPAN 300 000 MHz pg6168 c NOTE Hints Another capability that can be used for effect
394. ontinuously maintains the fastest sweep ti me possible with the selected measurement parameters Minimum Sweep Time The minimum sweep time is dependent on the following measurement parameters thenumber of points selected F bandwidth e sweep to sweep averaging in dual channel display mode error correction type of sweep 7 11 Operating Concepts Sweep Time In addition to the these parameters the actual cycle time of the analyzer is also dependent on the following measurement parameters smocthing limit test trace math marker statistics time domain Option 010 only Refer to the specifications and characteristics chapter of the reference guide to see the minimum cycle time values for specific measurement parameters 7 12 Operating Concepts Source Attenuator Switch Protection Source Attenuator Switch Protection The programmable step attenuator of the source can be switched between port 1 and port 2 when the test port power is uncoupled or between channel 1 and channel 2 when the channel power is uncoupled To avoid premature wear of the attenuator measurement configurations requiring continuous switching between different power ranges are not allowed For example continuous switching would be required if channels 1 and 2 of the analyzer are decoupled power levels in two different ranges are selected for each channel and dual channel display is engaged To prevent continuous switching betwe
395. oop structure NEW SEQ MODIFY SEQ SEQUENCE 1SEQ 1 SPECIAL FUNCTIONS DECISION MAKING LOOP COUNTER SELECT DISK INTERNAL DISK RETURN DEFINE DISK SAVE DATA ONLY ON SET ADDRESSES PLOTTER PORT DISK DO SEQUENCE SEQUENCE 2 DONE SEQ MODIFY NEW SEQ MODIFY SEQ SEQUENCE 2SEQ2 1 115 Making Measurements Using Test Sequencing to Test a Device FILE UTILITIES SEQUENCE FILE NAMING FILE NAME FILEO ERASE TITLE D T LOOP COUNTER DONE PLOT NAME PLOTFILE ERASE TITLE P L LOOP COUNTER DONE RETURN TRIGGER MENU SINGLE SAVE STATE PLOT SPECIAL FUNCTIONS DECISION MAKING DECR LOOP COUNTER IF LOOP COUNTER O SEQUENCE 2SEQ 2 DONE SEQ MODIFY This will create the following displayed lists Start of Sequence LOOP COUNTER 7 x1 INTERNAL DISK DATA ONLY ON DO SEQUENCE SEQUENCE 2 Start of Sequence FILE NAME DT LOOP PLOT NAME PL LOOP SINGLE SAVE FILE 0 DECR LOOP COUNTER IF LOOP COUNTER 0 THEN DO SEQUENCE 2 Sequence 1 initializes the loop counter and calls sequence 2 Sequence 2 repeats until the loop counter reaches O For each loop it takes a single sweep saves the data file and plots the display Thedata file names generated by this sequence will be DT00007 D1 through DT000001 D1 1 116 Making Measurements Using Test Sequencing to Test a Device The plot file names generated by this sequence will be PL00007 FP through
396. or 1 40 tracking the amplitude 1 41 spreadsheet saving test filefor a 4 43 spur avoidance understanding 5 17 spurious responses reducing the effect of 2 5 standards calibration 6 5 start frequency setting 1 34 starting the ripple test 1 85 statistics of measurement data calculating 1 42 stepped edit list menu 7 16 stepped edit subsweep menu 7 16 stepped list frequency sweep 7 15 segment menu 7 16 stepped edit list menu 7 16 stepped edit subsweep menu 7 16 stepped list mode 1 65 stimulus state error correction 6 9 stop frequencies minimum allowable 3 16 stop frequency setting 1 35 stopping a sequence 1 99 stopping the ripple test 1 85 storing exit HPGL mode and form feed sequence 4 24 HPGL initialization sequence 4 23 sequence on a disk 1 103 sweep rate decreasing 5 8 speed increasing 5 9 type setting 5 11 sweep time 7 11 auto sweep time mode 7 11 manual sweep time mode 7 11 minimum sweep time 7 11 sweep types 7 15 CW time sweep 7 19 Index linear frequency sweep 7 15 logarithmic frequency sweep 7 15 power sweep 7 19 selecting sweep modes 7 19 stepped list frequency sweep 7 15 swept list frequency sweep 7 17 Sweep to sweep averaging 7 8 swept edit list menu 7 17 swept edit subsweep menu 7 17 swept list frequency sweep 7 17 setting segment IF bandwidth 7 18 setting segment power 7 18 swept edit list menu 7 17 swept edit subsweep menu 7 17 swept list
397. or crosstalk from port 1 to port 2 with each port terminated The isolation part of the calibration is generally only necessary when measuring high loss devices greater than 70 dB NOTE If an isolation calibration is performed the fixture leakage must be the same during the isolation calibration and the measurement 7 68 Operating Concepts TRL LRM Calibration Figure 7 44 8 term TRL or TRL Error Model and Generalized Coefficients CH1 AYR log MAG 10 dB REF 70 dB Gat Hid P CH1 START 7 ns STOP 7 ns pq6121d Source match and load match ATRL calibration assumes a perfectly balanced test set architecture as shown by theterm which represents both the forward source match E se and reverse load match E pr and by the 5 term which represents both the reverse source match Esp and forward load match E p However in any switching test set the source and load match terms are not equal because the transfer switch presents a different terminating impedance as it is changed between port 1 and port 2 Because the standard network analyzer is based on a three sampler receiver architecture itis not possibleto differentiate the source match from the load match terms The terminating impedance of the switch is assumed to bethe same in either direction Therefore the test port mismatch cannot be fully corrected An assumption is made that forward source m
398. oset theintensity value between 50 and 100 percent Lowering theintensity may prolong thelife of the LCD Setting Default Colors To set all the display elements to the factory defined default colors press DEFAULT COLORS NOTE does not reset or change colors tothe default color values H owever cyding power to the instrument will reset the colors to the default color values The Modify Colors Menu The MODIFY COLORS softkey within the adjust display menu provides access to the modify colors menu The modify colors menu allows you to adjust the colors on your analyzer s display The default colors in this instrument were chosen to maximize your ability to discern the difference between the channel colors and to comfortably and effectively view the colors Each channel s memory trace color was chosen because the color is similar to the channels data trace color This allows easy association between the data trace and the memory trace for each channel You may choose to change the default colors to suit environmental needs individual preferences or to accommodate color deficient vision You can use any of the available colors for any of the display elements listed CH1 DATA LIMIT LN CH3 DATA LIMIT LN CH1MEM CH3MEM CH2 DATA LIMIT LN CH4 DATA LIMIT LN CH2MEM CH4 MEM GRATICULE REF LINE TEXT WARNING To change the color of a display elements press the softkey for that element such as CH1DATA Then press TINT and turn the analyz
399. ot protect the data if the instrument is turned off 6 33 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration Interpolation in Power Meter Calibration If the frequency is changed in linear sweep or the start stop power is changed in power sweep then the calibration data is interpolated for the new range If calibration power is changed in any of the sweep types the values in the power setting array areincreased or decreased toreflect the new power level Some accuracy is lost when this occurs Entering the Power Sensor Calibration Data Entering the power sensor calibration data compensates for the frequency response of the power sensor thus ensuring the accuracy of power meter calibration 1 7 Make sure that your analyzer and power meter are configured Refer to the Options and Accessories chapter of the reference guide for configuration procedures Press PWRMTR CAL LOSS SENSR LISTS CAL FACTOR SENSORA The analyzer shows the notation EMPTY if you have not entered any segment information Tocreatethe first segment press ADD FREQUENCY Enter the frequency of a correction factor data point as listed on the power sensor followed by the appropriate key kim Press CAL FACTOR and enter the correction factor that corresponds to the frequency that you have entered in the previous step Complete the correction factor entry by pressing DONE Repeat the previou
400. ou want to make a reflection measurement on PORT 2 in the reverse direction S22 press Refl REV S22 B R 3 Set any other measurement parameters that you want for the device measurement power sweep type number of points IF bandwidth 4 To access the measurement correction menus press 6 19 Calibrating for Increased Measurement Accuracy Frequency Response and Isolation Error Corrections 5 If your calibration kit is different than the kit specified under the CAL KIT softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in the displayed menu refer to Modifying Calibration Kits on page 7 56 6 To select a response and isolation correction and to start with the response portion of the calibration press CALIBRATE MENU RESPONSE amp ISOL N RESPONSE 7 Connect the short or open calibration standard to the port you selected for the test port PORT 1 for S44 or PORT 2 for S55 NOTE Indude any adapters that you will havein the device measurement That is connect the standard device to the particular connector where you will connect your device under test Figure 6 6 Standard Connections for a Response and Isolation Error Correction for Reflection Measurements NETWORK ANALYZER i L gummmmm qr s q pr pmmmmm Or For S Response Open Short I 1 1 1 1 1 1 For S Isolation For S Isolation 11 22 Load Load
401. ouais tiewe rinine ii bee e haw R ER Rcx pa de PR RR 1 43 Measuring Phase DISEOFTIOR 144 ic 0 06 eha0ee ba Eius kteri eri terien ire 1 45 Characterizing a DUDIEKE 513g sid EIS DEFERA AEST eT eRe E RR LERRA RES E R 1 49 DEHIEIDIB s 44 44 yore qu pp E TR Xd perd Tp decree P SHE dee P PRG Ie iE n deos 1 49 PrO GL i pbbagqicbesribePeb p aedairs amp debereBibzrbeibped d berddeieefieseieseds 1 49 D eas arg ANN IGI S 42g qe dba dol pce X Cea PREY CY de Ee do 9 4 d eb ea c 3e do ob BERS 1 53 Measuring harmonics Option O02 issu dati RR ERG RERTOYERPLTER d PEPAPAG x 1 54 Measuring Gain Eompr SON 44a qxaa qd Peribk iR PPGAG ER COE COR EQ pd a 1 59 Measuring Gain and Reverse Isolation Simultaneously 00 0c e eee eee 1 63 Using the Swept List Mode to Test a Device 0 0c ee 1 65 Connect the Device Under Test ci ccc tests deeeesee die beens Louies YA ECPHRERE KS 1 65 Observe the Characteristics of the Filter 2 0 e eee 1 66 Choose the Measurement Parameters 02 00 e eee eee 1 67 Canpa and MesSUre sadn tad od Rk SS ded o debe DOSE e XC e PER C e dan Pob ede S 1 69 Using Limit Lines To Test a Device LieweeddsIiPiesbsiSPpeRPkP TU E RERRQREEP4 ERR 1 71 Contents Setting Up the Measurement Parameters 0 002 cece eee 1 71 Creating Flat LIME EIBER 44 ccci rece deeeeerd EARR AR RPG PER 1 72 Creating a Slopine Lime Line ju caccuesdwwd ceeetadwes cde eens dee RE OR need 1 74 Cretino sanae Pont ENIDS
402. out charge on donation basis only from Free Software Foundation You may download this file using the information available on the following Web site ftp ots external hp com rfmw l ou To convert HPGL files to be used with other PC applications 1 Using the instructions on the Free Software Foundation website FTP the hp2xx file and save it on a floppy disk as hp2xx exe 2 Create the following batch file and save it on the same floppy disk as hpglconv bat The batch file consists of the following two lines echo off AX hp2xx exe m pcx 1 where A is the disk drive where the floppy disk in installed 3 Insert the floppy disk with the two files already installed into your analyzer 4 Make sure the measurement that you want to convert is displayed on the analyzer display 5 Create an HPGL file of the measurement and save it to the floppy disk by pressing SET ADDRESSES PLOTTER PORT DISK PLOT 6 Remove the floppy disk from the analyzer and insert it back into the PC 7 Using Explorer or File Manager click and drag the icon of the newly created hpgl file onto the icon of the hpglconv bat file This process creates a PCX format file from the hpgl file NOTE This conversion method has been used to convert many measurement displays H owever this conversion utility is not supported by Agilent Technologies Outputting Plot Files from a PC to a Plotter 1 Connect the plotter to an output port of the co
403. pensates for nominal power changes you make during a measurement so that the error correction still remains quite valid In these cases the cor annunciator will changeto cA 1 63 Making Measurements Measuring Amplifiers Figure 1 51 Gain and Reverse Isolation CH1 S21 log MAG 5 dB REF dB 1 19 549 dB 1 Pow r 45 dBm CH2 S log MAG 18 dB REF dB 1 36 376 dB 12 g START 1 000 MHz STOP 1 640 088 BAA MHz 1 64 Making Measurements Using the Swept List Mode to Test a Device Using the Swept List Mode to Test a Device When using a list frequency sweep the analyzer has the ability to sweep arbitrary frequency segments each containing a list of frequency points One major advantage of using list frequency sweep is that it allows you to measure the minimum number of data points and only at the frequencies of interest This serves to minimize the overall test time Two different list frequency sweep modes can be selected Stepped List Mode In this mode the source steps to each defined frequency point stopping while data is taken This mode eliminates IF delay and allows frequency segments to overlap H owever the sweep time is substantially slower than for a continuous sweep with the same number of points Swept List Mode This mode takes data while sweeping through the defined frequency segments increasing throughput b
404. played in red 1 85 Making Measurements Using Ripple Limits to Test a Device Figure 1 65 Filter Passband with Ripple Test Activated 1 Jun 2888 18 15 81 Hi sii Lac i dB REF 3 dB Channel 1 Ripple Test Result We LJ START 168 000 agg GHz STOP 3 500 000 688 GHz pa5198e As the analyzer measures the ripple a message is displayed indicating whether the measurement passes or fails ftheripple test passes a RIPLn PASS message where n the channel number is displayed in the color assigned to Channel 1 Memory The ripple test must pass in all frequency bands before the pass message is displayed e ftherippletest fails a RIPLn FAIL message where n the channel number is displayed in red The portion of the trace that exceeds the user specified maximum ripple valueis also displayed in red Displaying the Ripple Limits After the list of ripple limits has been set up display the ripple test limits by pressing RIPL LIMIT on OFF fromthe Ripple Test Menu until ON is displayed on the softkey Pressing this softkey toggles the analyzer ripple limits display on and off If the ripple limits are displayed and the ripple test is off the ripple limits are displayed near the top of the graticule and are not compared with the displayed trace H owever oncethe ripple test is started the ripple limits are displayed with respect to the measured trace in the
405. port can be connected to test fixtures power supplies and other peripheral equipment that might be used to interact with the analyzer during measurements This mode is exclusively used in test sequencing 7 80 Operating Concepts Limit Line Operation Limit Line Operation This menu can be accessed by pressing LIMIT MENU LIMIT LINE within the system menu You can have limit lines drawn on the display to represent upper and lower limits or device specifications with which to compare the test device Limits are defined in segments where each segment is a portion of the stimulus span Each limit segment has an upper and a lower starting limit value Three types of segments are available flat line sloping line and single point Limits can be defined independently for the four channels up to 22 segments for each channel These can bein any combination of thethree li mit types Limit testing compares the measured data with the defined limits and provides pass or fail information for each measured data point An out of li mit test condition is indicated in five ways with a FAIL message on the screen with a beep by changing the color of the failing portions of a trace with an asterisk in tabular listings of data and with a bit in the GPIB event status register B The analyzer also has a BNC rear panel output that indudes this status but is only valid for a single channel measurement NOTE Thelimit test output has three selectab
406. power sweep type ODO O O O O measurement parameter NOTE When the ac line power is switched off the internal non volatile memory is retained by a battery Refer to Specifications and Characteristics in the reference guide for data retention times 4 34 Printing Plotting and Saving Measurement Results Saving and Recalling Instrument States What You Can Save to a Floppy Disk You can save an instrument state and measurement results to a disk The default file names are FILEn wheren gets incremented by one each time a file with a default nameis added to the directory The default file names for data only files are DATAyDz DATAyDz for DOS where y is incremented by one each time a file with a default name is added to the directory The zis the channel where the measurement was made When you save a file to disk you can choose to save some or all of the following all settings listed for internal memory active error correction for the active channel only displayed measurement data trace displayed user graphics data only HPGL plots What You Can Save to a Computer Instrument states can be saved to and recalled from an external computer system controller using GPIB mnemonics For more information about the specific analyzer settings that can be saved refer to the output commands located in the Command Reference chapter of the programmer s guide For an example program refer to the Programming E xamples chap
407. press LIMIT MENU LIMITLINE LIMIT TESTON BEEP FAIL ON NOTE Selecting the beep fail indicator BEEP FAIL ON is optional and will add approximately 50 ms of sweep cycle time Because the limit test will still work if the limits lines are off selecting LIMIT LINE ON is also optional Thelimit test results appear on the right side on the analyzer display The analyzer indicates whether the filter passes or fails the defined limit test Themessage FAIL will appear on the right side of the display if the limit test fails Theanalyzer beeps if the limit test fails and if BEEP FAIL ON has been selected Theanalyzer changes the color of the traceto flashing red where the measurement traceis out of limits e ATTL signal on the rear panel BNC connector LIMIT TEST provides a pass fail 5 V O V indication of the limit test results 1 78 Making Measurements Using Limit Lines to Test a Device Offsetting Limit Lines Thelimit offset functions allow you to adjust the limit lines to the frequency and output level of your device For example you could apply the sti mulus offset feature for testing tunable filters Or you could apply the amplitude offset feature for testing variable attenuators or passband ripplein filters with variable loss This example shows you the offset feature and the limit test failure indications that can appear on the analyzer display 1 To offset all of the segments in the limit table by a fixed frequency
408. quency bands Whereas Frequency Bands 2 and 3 are separate bands that cover the same span of frequency This can be done to put tighter limits over narrower frequency spans within the bandpass or to customize the ripple test to meet your specific requirements 1 82 Making Measurements Using Ripple Limits to Test a Device To access the ripple test menu press LIMIT MENU RIPPLE LIMIT To access the ripple test edit menu press EDIT RIPL LIMIT Add the first frequency band Frequency Band 1 to betested by pressing ADD 4 Set thelower frequency value of Frequency Band 1 by pressing MINIMUM FREQUENCY Set theupper frequency value of Frequency Band 1 by pressing MAXIMUM FREQUENCY Set the maximum allowable ripple amplitude value of Frequency Band 1 by pressing MAXIMUM RIPPLE Repeat steps 3 through 6 for the two remaining frequency bands to be tested for maximum ri pple The network analyzer allows you to enter up to 12 frequency bands to be tested for maximum ri pple After you have entered all of the ripple test frequency band parameters return to the ripple test menu by pressing DONE Editing Ripple Test Limits Once the frequency band limits for ripple testing have been created the limits may be changed using the same menu that was used to create them Using the edit ripple test menu you may Change existing frequency band limits Add more frequency band limits Delete individual frequency
409. r display each instrument state is composed of numerous files which can be viewed on a PC NOTE If you have saved enough files that you have used all the default names FILEOO FILE31 for disk files or REG1 REG31 for memory files you must do one of the following to save more states e use another disk rename an existing file to make a default name available re save a file register deletean existing file register 4 36 Printing Plotting and Saving Measurement Results Saving Measurement Results Saving Measurement Results Instrument states combined with measurements results can only be saved to disk Files that contain data only and the various save options available under the DEFINE DISK SAVE key are also only valid for disk saves The analyzer stores data in arrays along the processing flow of numerical data from IF detection to display These arrays are points in the flow path where data is accessible usually via GPIB You can choose from three different arrays which vary in modification flexibility when they arerecalled raw data data raw data with error correction applied if correction is on otherwise raw data e format data processed to the display format If you choose to save the raw data array you will have the most flexibility in modifying the recalled measurement including the ability to view all four S parameters This is because the raw data array has the least amount of processing associa
410. r points to them This feature allows the sequence to be tested one command at a time f you wish to scroll through the sequence without executing each line as you do so you can press the X key and scroll through the command list backwards To enter the new command press the corresponding analyzer front panel keys For example if you want to activate the averaging function press AVERAGING ON Press DONE SEQ MODIFY to exit the modify edit mode Modifying a Command 1 To enter the creation editing mode press NEW SEQ MODIFY SEQ 2 To select the particular test sequence you wish to modify sequence 1 in this example press SEQUENCE 1SEQ1 1 100 Making Measurements Using Test Sequencing The following list is the commands entered in Creating a Sequence on page 1 97 Notice that for longer sequences only a portion of the list can appear on the screen at one time Start of Sequence RECALL PRST STATE Trans FWD S21 B R LOG MAG CENTER 134 M u SPAN 50 M u SCALE DIV AUTO SCALE 3 To change a command for example the span value from 50 MHz to 75 MHz movethe cursor next to the command that you wish to modify press Yo e f you use the Gs key to move the cursor through the list of commands the commands are actually performed when the cursor points to them This feature allows the sequence to be tested one command at a time e f you wish to scroll through the sequence withou
411. r the network analyzer receiver 1 66 Making Measurements Using the Swept List Mode to Test a Device Conversely the stopband of a filter generally exhibits high isolation To measure this characteristic the dynamic range of the system will have to be maximized This can be done by increasing the incident power and narrowing the IF bandwidth Choose the Measurement Parameters 1 Decide the frequency ranges of the segments that will cover the stopbands and passband of the filter For this example the following ranges will be used Lower stopband 650 to 880 MHz Passband 880 to 920 MHz Upper stopband 920 to 1150 MHz 2 Toset up the swept list measurement press SWEEP TYPE MENU EDIT LIST Set Up the Lower Stopband Parameters 3 Toset up the segment for the lower stopband press ADD START STOP NUMBER of POINTS 4 To maximize the dynamic range in the stopband increasing the incident power and narrowing thelF bandwidth press MORE LIST POWER ON off until ON is selected SEGMENT POWER LIST IF BW ON off until ON is selected SEGMENT IF BW RETURN DONE Set Up the Passband Parameters 5 Toset up the segment for the passband press ADD CENTER SPAN STEP SIZE 1 67 Making Measurements Using the Swept List Mode to Test a Device 6 To specify a lower power level and a wider IF bandwidth for the passband press MORE SEGMENT POWER SEGMENT IF BW 3700 RETURN DONE Set Up the Upper Stopband Parameters 7 To se
412. r the selected quadrant For example the analyzer would assign PLOTO1LU if there were no other left upper quadrant plots on the disk 5 Makethe next measurement that you want to see on your hardcopy 6 Repeat this procedure for the remaining plot files that you want to see as quadrants on a page If you want to see what quadrants you have already saved press to view the directory 4 29 Printing Plotting and Saving Measurement Results Titling the Displayed Measurement Titling the Displayed Measurement l Press MORE TITLE toaccess thetitle menu 2 Press ERASE TITLE and enter thetitle you want for your measurement display f you havea DIN keyboard attached tothe analyzer typethetitle you want from the keyboard Then press ENTER to enter the title into the analyzer You can enter a title that has a maximum of 50 characters For more information on using a keyboard with the analyzer refer to the Options and Accessories chapter of the reference guide f you do not have a DIN keyboard attached to the analyzer enter the title from the analyzer front panel a Turn the front panel knob to move the arrow pointer to the first character of the title b Press SELECT LETTER c Repeat the previous two steps to enter the rest of the characters in your title You can enter a title that has a maximum of 50 characters d Press DONE to complete the title entry Figure 4 12 Example of a Display Title CHI S2 tog MAG 1
413. r to accurately measure absolute power The following procedure shows you how to calibrate the receiver to any power level 1 Set the analyzer test port power to the desired level enter power level 2 Connect the power sensor to the analyzer test port 1 3 To apply the one sweep mode press PWRMTR CAL enter power level ONE SWEEP TAKE CAL SWEEP NOTE Because power meter calibration requires a longer sweep time you may want to reduce the number of points before pressing TAKE CAL SWEEP After the power meter calibration is finished return the number of points to its original value and the analyzer will automatically interpolate this calibration The status notation Pc will appear on the analyzer display Port 1 is now a calibrated source of power 4 Connect the test port 1 output to the test port 2 input 5 Choose a non ratioed measurement by pressing INPUT PORTS B TEST PORT 1 This sets the source at PORT 1 and the measurement receiver to PORT 2 or input port B 6 To perform a receiver error correction press CALIBRATE MENU RECEIVER CAL enter power level x1 TAKE RCVR CAL SWEEP The receiver channel now measures power to a characteristic accuracy of 0 35 dB or better The accuracy depends on the match of the power meter the source and the receiver 6 39 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Calibrating for Noninsertable Devices A test device that cannot
414. raging 5 15 chop sweep mode 5 12 display markers 1 25 fixed markers 1 29 limit test 1 78 activating the bandwidth test 1 94 active channel display 1 11 adapter removal 6 41 adapter removal calibration ECal 6 71 6 77 adapters minimizing error 6 49 adapters matched 6 46 ADC 7 7 address menu 7 79 addressing two sources 2 27 adjusting display colors 1 22 relative velocity factor 3 12 AmiPro using 4 21 amplifiers measuring 1 53 amplitude tracking 2 36 amplitude tracking 1 41 analog in menu 7 22 analyzer display formats 7 24 group delay format 7 25 group delay principles 7 29 imaginary format 7 29 linear magnitude format 7 27 log magnitude format 7 24 phase format 7 24 polar format 7 27 real format 7 29 smith chart format 7 26 SWR format 7 28 analyzer internal memory what you can save 4 34 applying power 8 5 arrays format 7 9 pre raw data 7 8 raw 7 8 ASCII data formats 4 40 CITIfile 4 40 S2P data format 4 40 assigning standards to various TRL classes 6 53 assigning standards to various TRM classes 6 57 attenuator 7 13 attenuator repetitive switching 7 13 auto sweep time mode 7 11 auto sweep time mode setting 5 11 auto feed selecting 4 13 autostarting sequences 1 105 averaging 7 34 isolation 6 63 averaging factor reducing 5 11 averaging activating 5 15 averaging sweep to sweep 7 8 band adding a frequency 1 84 changing a frequency 1 83 deleting a
415. ration allows you to offset the analyzer s source by a fixed value above or below the analyzer s receiver That is this allows you to use a deviceinput frequency range that is different from the receiver input frequency range Mixers or frequency converters by definition exhibit the characteristic of having different input and output frequencies Mixer tests can be performed using the frequency offset operation of the analyzer with an external LO source or using the tuned receiver operation of the analyzer with both an external RF and an external LO source The most common and convenient method used is frequency offset Frequency offset measurements do not begin until all of the frequency offset mode parameters are set These include the following Start and Stop IF Frequencies LO frequency U p Converter Down Converter RF gt LO RF LO The LO frequency for frequency offset mode must be set to the same value as the external LO source The offset frequency between the analyzer source and receiver will beset tothis value For a single sideband mixer measurement the RF source can be offset in frequency from the input receiver frequency allowing for a swept RF stimulus over one frequency range and measurement of the IF response over another in this case the output IF When frequency offset mode operation begins the receiver is tuned tothe entered IF signal frequencies and then offsets the source frequency required to produce the IF
416. rce Match a d S E pF Eep Vous R Unknown pg652d Frequency response tracking error is caused by variations in magnitude and phase flatness versus frequency between the test and reference signal paths These are due mainly to coupler roll off imperfectly matched samplers and differences in length and loss between the incident and test signal paths The vector sum of these variations is the reflection signal path tracking error Ege as shown in Figure 7 28 7 42 Operating Concepts Measurement Calibration Figure 7 28 Reflection Tracking Err E gr Frequency Tracking e gt SIM Y or s VY ua e 1 pg653d These three errors are mathematically related to the actual data S414 and measured data Sim by the following equation Sia ix Siim Epp t is Esp 911A If the value of these three E errors and the measured test device response were known for each frequency this equation could be solved for S444 to obtain the actual test device response Because each of these errors changes with frequency their values must be known at each test frequency These values are found by measuring the system at the measurement plane using three independent standards whose S444 is known at all frequendies The first standard applied is a perfect load which makes S114 0 and essentially measures directivity See Figure 7 29 Perfect load implies a reflectionless termination at the
417. rd No No No Yes Yes U ser defined preset No No No Yes Yes Non volatile memory in Kbytes 16 16 16 512 512 Dynamic range 30 kHz 3 GHz 100dB 100dB 100 dB 110 dB 100 dB Dynamic range 3 GHz 6 GHz N A 80 dB 80 dB 105 dB 110 dB Real time dock No No No Yes Yes a For this network analyzer the feature is dependent on the test set being used b 300 kHz to 3 GHz without Option 006 30 kHz to 6 GHz with Option 006 c 90 dB from 30 kHz to 50 kHz 100 dB from 300 kHz to 16 M Hz 7 89 Operating Concepts Differences between 8753 Network Analyzers Table 7 6 Comparing the 8753D E ES Feature 8753D 8753E 8753ES Fully integrated measurement system built in test set Yes Yes Yes Test port power range dBm 10 to 85 10 to 85 10 to 85 Auto manual power range selecting Yes Yes Yes Port power coupling uncoupling Yes Yes Yes Internal disk drive Yes Yes Yes Flash EPROM No Yes Yes Precision frequency reference Option 1D5 Yes Yes Yes Frequency range low end in kHz 30 30 30 Ext frequency range to 6 GHz Option 006 Yes Yes Yes 75Q system impedance Option 075 Yes Yes Yes TRL LRM correction Yes Yes Yes Power meter calibration Yes Yes Yes Interpolated error correction Yes Yes Yes Enhanced response calibration No Yes Yes Maximum error corrected measurement points 1601 1601 1601 Configurabl
418. re 3 2 Device Connections for Time Domain Transmission Example Measurement NETWORK ANALYZER X 0000 0000 0000 00 00 O88 00 Q 95 00 00 888 o 000 000 TEST POR CABLES JN SAW FILTER ADAPTERS pg68e 2 To choose the measurement parameters press Trans FWD S21 B R 119 149 Scale Ref AUTO SCALE 3 Substitute a thru for the device under test and perform a frequency response correction Refer to Chapter 6 Calibrating for Increased Measurement Accuracy 4 Reconnec your device under test Making Time Domain Measurements Making Transmission Response Measurements 5 Totransform the data from the frequency domain to the time domain and set the sweep from O s to 6 us press TRANSFORM MENU BANDPASS TRANSFORM ON 0 6 The other time domain modes low pass step and low pass impulse are described in Time Domain Low Pass Mode on page 3 15 6 To better view the measurement trace press Scale Ref REFERENCE VALUE and turn thefront panel knob or enter a value from the front panel keypad 7 To measure the peak response from the main path press Marker Search SEARCH MAX Thethree responses shown in Figure 3 3 arethe RF leakage near zero seconds the main travel path through the filter and thetriple travel path through the filter Only the combination of these responses was evident to you in the frequency domain Figure 3 3 Time Domain Transmis
419. rement displays to disk Li DATA ONLY ON If DATA ONLY ON data array is saved along with any other selected array the instrument state is not saved and therefore cannot berecalled 6 Choose the type of format you want m Choose SAVE USING BINARY for all applications except CITIfile S2P or CAE applications m Choose SAVE USING ASCII for CITIfile S2P and CAE applications or when you want to import the information into a spread sheet using comma separated values CSV format 7 Press RETURN SAVE STATE 4 39 Printing Plotting and Saving Measurement Results Saving Measurement Results ASCII Data Formats CITIfile CITIfile Common I nstrumentation Transfer and I nterchangefile is an ASCII data format that is useful when exchanging data between different computers and instruments CITIfiles are always saved when the ASCII format has been selected as shown DEFINE DISK SAVE Select one of the following choices DATA ARRAY ON DATA ONLY ON RAW ARRAY ON FORMAT ARY ON SAVE USING ASCII RETURN SAVE STATE If DATA ARRAY ON or DATA ONLY ON or FORMAT ARY ON isselected a CITIfileis saved for each displayed channel with the suffix letter D or F followed by a number The number following D and F files is the channel number When RAW ARRAY ON is selected an r1 file is saved for channel 1 channel 3 and an r5 file is saved for channel 2 channel 4 For more information on the CITIFile da
420. rement parameters that you want for the device measurement frequency span power sweep type number of points or IF bandwidth 6 60 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal Connect the ECal Equipment 1 Connect the power supply tothe PC interface unit Refer to Figure 6 21 Figure 6 21 ECal Setup NETWORK ANALYZER Parallel Port Connection Optional PC Interface ECal Module Unit PC Interface Power Supply to AC Power J pl502ets 2 Connect the power supply tothe ac source 3 Connect one end of a DB25 cableto the Parallel Port connector on the rear of the network analyzer Connect the other end of the DB25 cable to the connector on the PC interface unit labeled DB25 Interface to Parallel I nterface on Personal Computer CAUTION Only connect the DB25 cabletothe Parallel Port connector of the network analyzer If the cable is connected to the Test Set I O Interconnect connector damage to the PC interface unit could occur NOTE For steps 3 through 5 use the three DB25 cables part number 8120 8710 shipped with the 85097A Electronic Calibration System Other cables may not give reliable results 4 Connect one end of a DB25 cable to the connector on the PC interface unit labeled DB25 Interface to E Cal Module A Connect the other end of the DB25 cable to the parallel cable connector on the ECal module 6 61 Calibrating for Increased Mea
421. remove unwanted responses isolated in time In thetime domain this can be viewed as a time selective bandpass or bandstop filter If both data and memory are displayed gating is applied to the memory trace only if gating was on when data was stored into memory The Electrical Delay Block This block involves adding or subtracting phase in proportion to frequency This is equivalent to line stretching or artificially moving the measurement reference plane This block also includes the effects of port extensions as well as electrical delay 7 8 Operating Concepts Processing Conversion This converts the measured S parameter data to the equivalent complex impedance Z or admittance Y values or to inverse S parameters 1 S Transform Option 010 Only This transform converts frequency domain information into the time domain when it is activated The results resemble time domain reflectometry TDR or impulse response measurements The transform uses the chirp Z inverse fast Fourier transform FFT algorithm to accomplish the conversion The windowing operation if enabled is performed on the frequency domain data just before the transform A special transform mode is available to demodulate CW sweep data with time as the stimulus parameter and display spectral information with frequency as the stimulus parameter Format This operation converts the complex number pairs into a scalar representation for display according
422. rent colors may be assigned to the pen numbers Table 4 2 Default Pen Numbers and Corresponding Colors Pen Number Color Pen Number Color 0 white 4 yellow 1 cyan 5 green 2 magenta 6 red 3 blue 7 black Table 4 3 Default Pen Numbers for Plot Elements Corresponding Key Plot Element Pen Numbers Channel 1 Channel 2 PEN NUM DATA M easurement Data Trace 2 3 PEN NUM MEMORY Displayed M emory Trace 5 6 PEN NUM GRATICULE Graticuleand Reference Line 1 1 PEN NUM TEXT Displayed Text 7 7 PEN NUM MARKER Displayed Markers and Values 7 7 NOTE You can set all the pen numbers to black for a plot in black and white You must define the pen numbers separately for each measurement channel channel 1 3 and channel 2 4 4 14 Printing Plotting and Saving Measurement Results Defining a Plot Function Selecting Line Types Press MORE and select each plot element line type that you want to modify Select LINE TYPE DATA to modify the line type for the data trace Then enter the new line type see Figure 4 6 followed by x1 Select LINE TYPE MEMORY to modify the linetype for the memory trace Then enter the new line type see Figure 4 6 followed by x1 Table 4 4 Default Line Types for Plot Elements Plot Elements Channel 1 Line Type Numbers Channel 2 Line Type Numbers Data Trace 7 7 M emory Trace 7 7 Figure 4 6 Line Types Available
423. rigger type gating parameters sweep type power meter calibration Coupling of stimulus values for the two channels is independent of DUAL CHAN on OFF in the display menu and MARKERS UNCOUPLED in the marker mode menu COUPLED CH OFF activates an alternate sweep function when dual channel display is on In this mode the analyzer alternates between the two sets of stimulus values and displays the measurement data of both channels 7 14 Operating Concepts Sweep Types Sweep Types Thefollowing sweep types will function with the interpolated error correction feature described in I nterpolated Error Correction on page 6 8 linear frequency power sweep e CW time The following sweep types will not function with the interpolated error correction feature logarithmic frequency sweep list frequency sweep Linear Frequency Sweep Hz The LIN FREQ softkey activates a linear frequency sweep that is displayed on a standard graticule with ten equal horizontal divisions This is the preset default sweep type For a linear sweep sweep time is combined with the channel s frequency span to compute a source sweep rate sweep rate frequency span sweep ti me Since the sweep ti me may be affected by various factors the equation provided hereis merely an indication of the ideal fastest sweep rate If the user specified sweep time is greater than 15 ms times the number of points the sweep changes from a continuou
424. rinter Connections to the Analyzer GPIB Parallel RS 232 Port Serial Port 2 Press Local SET ADDRESSES PRINTER PORT PRNTR TYPE until the correct printer choice appears T Think et Quiet et LY Deskj et This supports most current models such as Desk et 890C Desk et 895C or Desk et 1600C See also DJ 540 selection 14 Laser et only Laser et models III 4 5 and 6 Paint et m Epson P2 printers that conform to the ESC P2 printer control language such as Epson LQ 570 T DJ 540 This can be used for printers that do not support 100 dots per inch dpi but do support 300 dpi such as HP Desk et 540 or 850C L NOTE Selecting DJ 540 converts 100 dpi raster information to 300 dpi raster format If your Deskj et printer does not support the 100 dpi raster format and your printing results seem to be smaller than the normal size approximately one half of the page select DJ 540 Information regarding a printer compatibility guide an up to date list of printers that are compatible with the network analyzer is available in Printing or Plotting Your Measurement Results on page 4 3 4 4 Printing Plotting and Saving Measurement Results Configuring a Print Function 3 Select one of the following printer interfaces NOTE Choose PRNTR PORT GPIB if your printer has a GPIB interface and then configure the print function as follows a Enter the GPIB address of the printer followed by x1 b Press
425. rmed back to the frequency domain For reflection or fault location measurements use this feature to remove the effects of unwanted discontinuities in the time domain You can then view the frequency response of the remaining discontinuities n a transmission measurement you can remove the effects of multiple transmission paths Figure 3 26a shows the frequency response of an electrical airline and termination Figure 3 26b shows the response in the time domain The discontinuity on the left is due tothe input connector The discontinuity on the right is due to the termination We want to remove the effect of the connector so that we can see the frequency response of just the airline and termination Figure 3 26c shows the gate applied to the connector discontinuity Figure 3 26d shows the frequency response of the airline and termination with the connector gated out Figure 3 26 Sequence of Steps in Gating Operation CGAITNG ORERAI ION N f t Frequency Time Domain Domain O A pb666d Setting the Gate Think of a gate as a bandpass filter in the time domain see Figure 3 27 When the gate is on responses outside the gate are mathematically removed from the time domain trace Enter the gate position as a start and stop time not frequency or as a center and span time The start and stop times are the bandpass filter 6 dB cutoff times Gates can havea negative span in which casethe responses ins
426. rmining the Electrical Delay Setup NETWORK ANALYZER NETWORK ANALYZER Reference Reference Reference Port 1 Port 1 Port 2 Step A Step B pl512ets c Connect the A3 adapter to Reference Port 1 as shown in Step B of Figure 6 14 Attach the short from the calibration kit for port 2 to the other end of the adapter You must know the delay of the short The delay of the short can be found in the calibration kit that you are using Typical delays of shorts are 31 7 ps for the short from the 85052D calibration kit and 31 8 ps for the short from the 85033D calibration kit d Measurethe delay of the adapter and short together by pressing DELAY e Divide the resulting delay measurement by 2 to determine the delay of the thru and the short in one direction f Subtract the offset delay of the short determined in step c from the delay of the thru and the short in one direction determined in step e Theresult is the electrical delay of the thru This valueis used in the Step 12 g Removethe short from the adapter 6 42 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices NOTE You must use the floppy disk to store the following calibrations Select the floppy disk by pressing Save Recall SELECT DISK INTERNAL DISK 3 Connect adapter A3 same sex and connector type as the DUT to adapter A2 on port 2 as shown in Figure 6 15 Figure 6 15 Two Port Cal Set 1 NETWORK ANALYZER Referen
427. ror Corrections 11 To measure the calibration standard press RESUME CAL SEQUENCE ISOL N STD 12 Return the averaging tothe original state of the measurement For example reduce the averaging factor by at least four times or turn averaging off 13 To compute the isolation error coefficients press RESUME CAL SEQUENCE DONE RESP ISOL N CAL The analyzer displays the corrected data trace The analyzer also shows the notation Cor at the left of the screen indicating that the correction is switched on for this channel NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures 14 This completes the response and isolation correction for transmission measurements You can connect and measure your device under test Response and Isolation Error Correction for Reflection Measurements Theresponse and isolation error correction for reflection measurements provides the following benefits removes frequency response of the test setup removes isolation in transmission measurements removes directivity in reflection measurements To perform the response and isolation error correction for reflection measurements 1 Press Preset 2 Select the type of measurement you want to make 1 If you want to make a reflection measurement on PORT 1 in the forward direction 513 leave the instrument default setting OY If y
428. s 3 14 forward transform horizontal axis 3 23 forward transform vertical axis 3 22 low pass response horizontal axis 3 16 low pass response vertical axis 3 17 low pass step transmission response horizontal axis 3 20 low pass step transmission response vertical axis 3 20 introduction to time domain measurements 3 3 isolation 7 40 7 68 averaging 6 63 calibrating using ECal 6 63 calibration omitting 6 4 error corrections and frequency response 6 17 isolation example measurements 2 42 LO toRF isolation 2 42 RF feedthrough 2 45 SWR return loss 2 48 J jpeg files saving results as 4 45 K knowing the instrument modes 7 83 L labeling the screen 2 30 leakage signals eliminating unwanted 2 6 limit line operation 7 81 edit limits menu 7 82 edit segment menu 7 82 offset limits menu 7 82 limit lines creating flat limit lines 1 72 Index 5 Index creating single point limits 1 76 editing line segments 1 77 measurement parameters 1 71 offsetting limit lines 1 79 running a limit test 1 77 sloping limit line 1 74 using to test a device 1 71 limit test decision making 1 111 example sequence 1 117 limit test running 1 77 activating the limit test 1 78 reviewing the limit line segments 1 77 line segments editing 1 77 deleting line segments 1 77 linetypes selecting 4 15 linear frequency sweep 7 15 linear magnitude format 7 27 linear phase deviation 1 46 linear s
429. s press SEGMENT and follow the previous steps starting with step 2 Deleting Frequency Segments 1 Access the Segment Modify menu by pressing PWRMTR CAL LOSS SENSR LISTS CAL FACTOR SENSOR A or CAL FACTOR SENSORB depending on where the segment is that you want to delete Identify the segment that you want to delete by pressing SEGMENT and usingthe x and X keys to locate and position the segment next to the pointer gt shown on the display Or press SEGMENT and enter the segment number followed by x1 Press DELETE The analyzer deletes the segment and moves the remainder of the segments up one number You could also delete all the segments in a list by pressing CLEAR LIST YES 5 Press DONE when you are finished modifying the segment list Compensating for Directional Coupler Response If you use a directional coupler to sample power in your measurement configuration you should enter the coupled arm power loss value into the power loss table using the following procedure You can enter the loss information in a single segment and the analyzer will assume that the value applies to the entire frequency range of the instrument Or you can input actual measured power loss values at several frequencies using up to 12 segments enhancing power accuracy l Press PWRMTR CAL LOSS SENSR LISTS POWER LOSS The analyzer shows the notation EMPTY if you have not entered any segment information Tocreate
430. s for performing a 2 port error correction for each connector type Only recognized cal kit standards are available SSMA SM X GPO and similar connectors have no recognized traceable cal kit standards Specified electrical length of adapter A3 within 1 4 wavelength for the measurement frequency range For each port a separate 2 port error correction is performed the first at the connection between A1 and A3 and the second at the connection between A2 and A3 The error coefficients are stored in separate calibration sets After these calibrations the two calibration sets are combined and with knowledge of the electrical length of the adapter A3 a separate third calibration set is created This cal set contains error coefficients that accurately represent the characteristics of Port 1 and Port 2 as if A1 and A2 were actually connected together to measure forward and reverse match and tracking terms 6 41 Calibrating for Increased Measurement Accuracy Calibrating for Noninsertable Devices Perform the 2 Port Error Corrections 1 Check the firmware to see if your revision supports adapter removal calibration by pressing MORE ADAPTER REMOVAL HELP ADAPT REMOVAL 2 Determinethe delay of adapter A3 a Refer to Figure 6 14 while performing the steps in this procedure Also refer to page 6 41 for an explanation of A1 A2 and A3 b Perform a 1 port calibration at Reference Port 1 Refer to Step A of Figure 6 14 Figure 6 14 Dete
431. s not activated the analyzer finds the specified amplitude on the current sweep and the marker remains at same stimulus value regardless of changes in thetrace response value with subsequent sweeps 1 41 Making Measurements Using Markers To Calculate the Statistics of the Measurement Data This function calculates the mean standard deviation and peak to peak values of the section of the displayed trace between the active marker and the delta reference If there is no delta reference the analyzer calculates the statistics for the entire trace 1 Move marker 1 to any point that you want to reference e Turn the front panel knob OR Enter the frequency value on the numeric keypad 2 Press A MODE MENU AREF 1 tomake marker 1 a reference marker 3 Press MARKER 2 and move marker 2 to any position that you want to measure in reference to marker 1 4 Press MKR MODE MENU MKR STATS ON to calculate and view the mean standard deviation and peak to peak values of the section of the measurement data between the active marker and the delta reference marker An application for this feature is to find the peak to peak value of passband ripple without searching separately for the maxi mum and minimum values If you are viewing a measurement in the polar or Smith Chart format the analyzer calculates the statistics using the first value of the complex pair magnitude real part resistance or conductance Figure 1 32 Example Statisti
432. s ramp sweep to a stepped CW sweep Also for 10 Hz or 30 HzIF bandwidths the sweep is automatically converted to a stepped CW sweep In the linear frequency sweep mode it is possible with Option 010 to transform the data for time domain measurements using the inverse Fourier transform technique Logarithmic Frequency Sweep Hz The LOG FREQ softkey activates a logarithmic frequency sweep mode The source is stepped in logarithmic increments and the data is displayed on a logarithmic graticule This is slower than a continuous sweep with the same number of points and the entered sweep time may therefore be changed automatically For frequency spans of less than two octaves the sweep type automatically reverts to linear sweep Stepped List Frequency Sweep Hz The LIST FREQ STEPPED softkey activates a stepped list frequency sweep one of two list frequency sweep modes The stepped list mode allows the analyzer to sweep a list of arbitrary frequency points This list is defined and modified using the edit list menu and the edit subsweep menu U p to 30 frequency subsweeps called segments of several different types can be specified for a maximum total of 1601 points 7 15 Operating Concepts Sweep Types NOTE Earlier 8753 models allowed a maximum of 1632 points but this value was reduced to 1601 to add the 4 channels in the 4 parameter display feature One list is common to both channels Once a frequency list has been defined
433. s required for a connector interface different from the four default calibration kits Examples SMA TNC or waveguide A calibration with standards or combinations of standards that are different from the default calibration kits is required Example Using three offset shorts instead of open short and load to perform a 1 port calibration The built in standard models for default calibration kits can be improved or refined Remember that the more closely the model describes the actual performance of the standard the better the calibration Example The 7 mm load is determined to be 50 4 Q instead of 50 0 Q Definitions The following are definitions of terms A standard represented by a number 1 8 is a specific well defined physical device used to determine systematic errors For example standard 1 is a short in the 3 5 mm calibration kit Standards are assigned to the instrument softkeys as part of a dass A standard type is one of five basic types that define the form or structure of the model to be used with that standard short open load delay thru and arbitrary impedance standard 1 is of thetype short in the 3 5 mm calibration kit e Standard coefficients are numerical characteristics of the standards used in the model selected For example the offset delay of the short is 32 ps in the 3 5 mm calibration kit A standard dass is a grouping of one or more standards that determines which of the eigh
434. s that the complex impedance is capacitive in the bottom half of the Smith chart display and is inductive in the top half of the display Choose LIN MKR if you want the analyzer to show the linear magnitude and the phase of the reflection coefficient at the marker Choose LOG MKR if you want the analyzer to show the logarithmic magnitude and the phase of the reflection coefficient at the active marker This is useful as a fast method of obtaining a reading of thelog magnitude value without changing to log magnitude format Choose Refim MKR if you want the analyzer to show the values of the reflection coefficient at the marker as a real and imaginary pair Choose R4jK MKR to show thereal and imaginary parts of the device impedance the series resistance and reactance in ohms at the marker Also shown is the equivalent series inductance or capacitance Choose G B MKR to show the complex admittance values of the active marker in rectangular form The active marker values are displayed in terms of conductance in Siemens susceptance and equivalent parallel circuit capacitance or inductance Siemens arethe international unit of admittance and are equivalent to mhos the inverse of ohms 1 33 Making Measurements Using Markers Figure 1 21 Example of Impedance Smith Chart Markers CH1 84 1i UFS 2 20 117 n 68 178 a 21 649 nH 442 398 S01 MHz START 030 O08 MHz STOP E 880 008 808 MHz aw000038 To Set Measurement Parameters Using
435. s the ti me domain response of an impulse input like the bandpass mode Both low pass modes yield better time domain resolution for a given frequency span than does the bandpass mode n addition when using the low pass modes you can determine the type of discontinuity H owever these modes have certain limitations that are defined in Time Domain Bandpass M ode on page 3 12 The analyzer has one ti me to frequency transform mode Forward transform mode transforms CW signals measured over time into the frequency domain to measure the spectral content of a signal This modeis known as the CW time mode Making Time Domain Measurements Making Transmission Response Measurements Making Transmission Response Measurements In this example measurement there are three components of the transmission response RF leakage at near zero time e themain travel path through the device 1 6 us travel time e the tripletravel path 4 8 us travel time This example procedure also shows you how time domain analysis allows you to mathematically remove individual parts of the time domain response to see the effect of potential design changes This is accomplished by gating out the undesirable responses With the gating capability the analyzer time domain allows you to perform what if analysis by mathematically removing selected reflections and seeing the effect in the frequency domain 1 Connect the device as shown in Figure 3 2 Figu
436. s three steps to enter up to 55 frequency segments You may enter multiple segments in any order becausethe analyzer automatically sorts them and lists them on the display by frequency value The analyzer also automatically interpolates the values between correction factor data points f you only enter one frequency segment the analyzer assumes that the single value is valid over the entire frequency range of the correction After you have entered all the frequency segments press DONE Editing Frequency Segments 1 Access the Segment Modify menu by pressing PWRMTR CAL LOSS SENSR LISTS CAL FACTOR SENSOR A or CAL FACTOR SENSOR B depending on where the segment is that you want to edit Identify the segment that you want to edit by pressing SEGMENT and using the and X keys to locate and position the segment next to the pointer gt shown on the display Or press SEGMENT and enter the segment number followed by x7 Press EDIT and then press either the FREQUENCY or CAL FACTOR key depending on which part of the segment you want to edit 6 34 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration OV If you are modifying the frequency enter the new value followed by a Gn M or key L If you are modifying the correction factor enter the new value followed by the key Press DONE after you have finished modifying the segment 5 If you want to edit any other segment
437. se two points is the bandwidth of the filter This bandwidth is compared to minimum and maximum allowable bandwidths that you specify during the test setup This example shows you how to test the bandwidth of a bandpass filter n this example we will betesting the pass band of a bandpass filter where the center frequency of the filter is approximately 321 M Hz Refer to Figure 1 69 Figure 1 69 Bandpass Filter Being Bandwidth Tested 15 Jun 2888 13 11 43 Hi 21 Los i dB REF 45 19 dB 1 5 2758 dB 321 666 666 GHz in MI i START 871 00A 666 GHz STOP S7i 000 666 GHz pa5195e Setting Up Bandwidth Limits When you set up the bandwidth limits to test the bandpass filter you will first set up the analyzer to perform the bandwidth test and then you will set up bandwidth limits of the bandwidth test Setting Up the Analyzer to Perform the Bandwidth Test This section sets up the analyzer so that a bandpass filter can be easily viewed on the analyzer display 1 Connect your filter as shown in Figure 1 70 1 91 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter Figure 1 70 Connections for a Bandpass Filter Example Measurement NETWORK ANALYZER pa53e 2 Press and choose the measurement settings For this example the measurement settings are as follows a Trans FWD S21 B R b c d AUTO SCALE You may also want to select
438. set the GPIB address of the analyzer and enter the addresses of peripheral devices so that the analyzer can communicate with them Most of the GPIB addresses are set at the factory and need not be modified for normal system operation The standard factory set addresses for instruments that may be part of the system are as follows Instrument GPIB Address decimal Analyzer 16 Plotter 05 Printer 01 External Disk Drive 00 Controller 21 Power Meter 13 The address displayed in this menu for each peripheral device must match the address set on the device itself The analyzer does not have a GPIB switch its address is set only from the front panel These addresses are stored in non volatile memory and are not affected by preset or by cyding the power Using the Parallel Port Theinstrument s parallel port can be used in two different modes By pressing and then toggling the PARALLEL softkey you can select either the COPY mode or the GPIO mode The Copy Mode The copy mode allows the parallel port to be connected to a printer or plotter for the outputting of test results To use the parallel port for printing or plotting you must do the following 1 Press SET ADDRESSES 2 Select either PLOTTER PORT or PRINTER PORT 3 Select PARALLEL so that copy is underlined 7 79 Operating Concepts GPIB Operation The GPIO Mode The GPIO modeturns the parallel port into a general purpose input output port In this mode the
439. settings for the number of data points power averaging and IF bandwidth Figure 1 71 Filter Pass Band Before Bandwidth Test 15 Jun 2088 12 23 17 Hi 521 LoG 18 dB REF 38 dB PRm Cor 1p dB di an ls E y ba CENTER 321 960908 GHz SPAN 2080 666 606 GHz pasigie 1 92 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter 3 Substitute a thru for the device and perform a response calibration by pressing CALIBRATE MENU RESPONSE THRU 4 Reconnect your test device Refer to Figure 1 71 Setting Up the Bandwidth Limits When you set up the bandwidth limits to test the bandpass filter you will set the amplitude below the peak that is used to measure the filter s bandwidth This setting is called N dB Points the Maximum Bandwidth value If the measured bandwidth is greater than this value the test will fail the Minimum Bandwidth value If the measured bandwidth is less than this value the test will fail To access the bandwidth menu press LIMIT MENU BANDWIDTH LIMIT Toset the amplitude below the peak passband amplitude that you want to measure the bandwidth In this case we are setting the bandwidth that will be measured 40 dB below the peak amplitude of the bandpass filter by pressing N DB POINTS Toset the minimum bandwidth for the bandwidth test press MINIMUM BANDWIDTH Toset the maximum bandwidth
440. siderations Figure 6 1 Typical Responses of Calibration Standards after Calibration CH1 S4 1 U FS 1 998 84 mU 179 92 3 000 000 000 MHz Cor 4 START 300 000 MHZ STOP 3 000 000 000 MHZ 7mm or Type N Male Short No Offset CH1 S44 1 U FS 1 998 25 mU 11 779 3 000 000 000 MHz Cor START 300 000 MHZ STOP 3 000 000 000 MHZ 7mm or Type N Male Open No Offset with Fringing Capacitance Interpolated Error Correction CH1 S4 1 U FS 1 999 62 mU 142 07 i 000 000 000 MHz START 300 000 MHZ STOP 3 000 000 000 MHZ Type N Female 3 5mm Male or Female Offset Short CH1 S4 1 U FS 1 999 1 mU 44 561 OG 000 000 000 MHz START 300 000 MHZ STOP 3 000 000 000 MHZ Type N Female 3 5 mm Male or Female Offset Open pa5162e You may want to use interpolated error correction when you choose a subset of a frequency range that you already corrected when you change the number of points or when you change to CW This feature also allows you to change the parameters in a 2 port correction such as IF bandwidth power or sweep time The analyzer calculates the systematic errors from the errors of the original correction 6 8 Calibrating for Increased Measurement Accuracy Calibration Considerations To activate interpolated measurement correction press INTERPOL ON off sothat ON is selected and CORRECTION on OFF sothat ON is selected When interpolation is in use the notation CA will appear on the analyzer display
441. sing This Chapter This chapter describes techniques and analyzer functions that help you achieve the best measurement results The following topics are included in this chapter Increasing Measurement Accuracy on page 5 4 d Coouceou eo Interconnecting cables Improper calibration techniques Sweeping too fast for electrically long devices Connector repeatability Temperature drift Frequency drift Performance verification Reference plane and port extensions Making Accurate M easurements of Electrically Long Devices on page 5 7 Increasing Sweep Speed on page 5 9 Increasing Dynamic Range on page 5 14 Reducing Noise on page 5 15 Reducing Receiver Crosstalk on page 5 16 e Reducing Recall Time on page 5 17 5 2 Optimizing Measurement R esults Taking Care of Microwave Connectors Taking Care of Microwave Connectors Proper connector care and connection techniques are critical for accurate repeatable measurements Refer tothe calibration kit documentation for connector care information Prior to making connections to the network analyzer carefully review the information about inspecting cleaning and gaging connectors Having good connector care and connection techniques extends the life of these devices In addition you obtain the most accurate measurements This type of information is typically located in chapter 3 of the calibration kit manuals For additional connector care i
442. sion Example Measurement Main Travel Path dB REF SO dB 1 24 959 dB 1 59 ps CHi So tog MAG l 1 69 ps 476 67 m Triple Travel Path RF Leakage CH1 START s STOP 6 ps pa5165e 8 To access the gate function menu press TRANSFORM MENU SPECIFY GATE CENTER 9 To set the gate parameters by entering the marker value press M or turn the front panel knob to position the center gate marker This marker shaped likea T is shown in Figure 3 4 10 To set the gate span press or turn the front panel knob to position the flag gate markers Making Time Domain Measurements Making Transmission Response Measurements 11 To activate the gating function to remove any unwanted responses press GATE ON As shown in Figure 3 4 only response from the main path is displayed NOTE You may remove the displayed response from inside the gate markers by pressing SPAN and turning the front panel knob to exchange the flag marker positions Figure 3 4 Gating in a Time Domain Transmission Example Measurement CHi S log MAG ig dB REF 50 dB hU T Tr T CH1 START s STOP 6 ys aw000023 12 To adjust the gate shape for the best possible time domain response press GATE SHAPE and select between minimum normal wide and maximum E ach gate has a different passband flatness cuto
443. size 1 105 stopping 1 99 storing to disk 1 103 sequencing special functions menu 1 111 test 1 97 service menu ECal 6 69 servicing 8 6 setting auto sweep time mode 5 11 frequency range for time domain low pass 3 15 gate 3 35 setting ripple limits 1 80 1 83 setting segment IF bandwidth 7 18 setting segment power 7 18 setting the sweep type 5 11 setting up bandwidth test limits 1 91 1 93 shipment for service 8 2 sidelobes 3 27 single page plots outputting using a printer 4 24 single point limits 1 76 single channel operation 1 57 7 87 sloping limit line 1 74 small signal transient response measuring 3 19 smith chart format 7 26 smith chart markers 1 33 smocthing 7 9 7 35 softkey 4 Param Displays 1 18 channel position 1 17 solving problems with printing or plotting 4 33 solving problems with saving or recalling files 4 53 using an external disk drive 4 53 source attenuator switch protection 7 13 repetitive switching of the attenuator 7 13 Source match 7 39 source match and load match 7 69 source mismatches minimizing 2 4 Source power setting 1 5 S parameter menu analog in menu 7 22 conversion menu 7 22 S parameters 7 20 S parameter menu 7 22 understanding 7 20 S parameters menu input ports menu 7 23 specific amplitude 1 39 bandwidth searching for 1 41 maximum amplitude searching for 1 39 minimum amplitude searching for 1 39 target amplitude searching f
444. so they must be treated as producing a cumulative uncertainty in the measured data Directivity Normally a device that can separate the reverse from the forward traveling waves a directional bridge or coupler is used to detect the signal reflected from the test device Ideally the coupler would completely separate the incident and reflected signals and only the reflected signal would appear at the coupled output as shown in Figure 7 21a Figure 7 21 Directivity Coupled Coupled Output Output F1 A input MGE Main V p d Main Input Coupler CJ Coupler N Output l l Output Incident Incident lt gt Reflected Reflected b Ideal Coupler b Actual Coupler pg646d 7 38 Operating Concepts Measurement Calibration However an actual coupler is not perfect as shown in Figure 7 21b A small amount of the incident signal appears at the coupled output due to leakage as well as reflection from the termination in the coupled arm Also reflections from the coupler output connector appear at the coupled output adding uncertainty to the signal reflected from the device The figure of merit for how well a coupler separates forward and reverse waves is directivity The greater the directivity of the device the better the signal separation System directivity is the vector sum of all leakage signals appearing at the analyzer receiver input The error contributed by directivity is independent of the char
445. splayed is based on the assumption that the signal travels at the speed of light The signal travels slower than the speed of light in most media e g coax cables This slower velocity relative to light can be compensated for by adjusting the analyzer relative velocity factor To determine the physical length rather than the electrical length change the velocity factor to that of the medium under test 1 Press Cal MORE VELOCITY FACTOR 2 Enter a velocity factor between 0 and 1 0 1 0 corresponds to the speed of light in a vacuum Most cables have a velocity factor of 0 66 polyethylene dielectrics or 0 70 teflon dielectrics NOTE To cause the markers to read the actual one way distance to a discontinuity rather than the two way distance enter one half the actual velocity factor Reflection Measurements Using Bandpass Mode The bandpass mode can transform reflection measurements to the time domain Figure 3 10 left shows a typical frequency response reflection measurement of two sections of cable Figure 3 10 right shows the same two sections of cable in the time domain using the bandpass mode 3 12 Making Time Domain Measurements Time Domain Bandpass Mode Figure 3 10 A Reflection Measurement of Two Cables NETWORK ANALYZER o 00 oBB o 1 0000 0000 oo 900 NC ADAPTER LOAD CH1 S11 log MAG 10 dB REF 40 dB 1 47 216 dB CH1 S411 lin MAG 10 mU REF O U 1 62
446. sponse and response and isolation calibrations the parameter must be selected before calibration Other correction procedures select parameters automatically Changing channels during a calibration procedure invalidates the part of the procedure already performed Device Measurements In calibration procedures that require measurement of several different devices for example a short an open and a load the order in which the devices are measured is not critical Any standard can be re measured until the DONE key is pressed The change in trace during measurement of a standard is normal Response and response and isolation calibrations require measurement of only one standard device If more than one device is measured only the data for the last device is retained Clarifying Type N Connector Sex When you are performing error correction for a system that has type N port connectors the softkey menus label the sex of the test port connector not the calibration standard connector For example the label SHORT F refers to the short that will be connected to the female test port Since many devices have type N f connectors the calibration standard to select is the type N m Be sure to use the port extension pin on the type N m Open calibration standard NOTE Since the 85032F calibration kit offsets are equal for both male and female connectors the standard s sex type is not requested during the calibration Omitting Isola
447. st for possible causes Look in the analyzer display message area The analyzer may show a message that will identify the probl em Refer tothe Error Messages chapter of the reference guide if you View a message Make sure that you are NOT using a single sided floppy disk in the analyzer disk drive Make sure that you are using a formatted disk Make sure that the disk has not been formatted with the LIF HFS hierarchical file System extensions as the analyzer does not support this format If You Are Using an External Disk Drive Make surethat the analyzer is in system controller mode by pressing SYSTEM CONTROLLER Make sure that you have connected the disk drive to ac power switched on the power and connected a GPIB cable between the disk drive and the analyzer Make surethat the analyzer recognizes the disk drive s GPIB address as explained in If You Are Plotting Measurement Results to a Disk Drive on page 4 11 Make surethat the analyzer recognizes the disk drive unit that you selected 0 or 1 If the external disk is a hard disk make surethat the disk volume number is set correctly If the disk drive is an older HP 9122 it may not recognize the newer high density disks Substitute the GPIB cable Substitute the disk drive 4 53 Printing Plotting and Saving Measurement Results Formatting a Disk 4 54 5 Optimizing Measurement Results 5 1 Optimizing Measurement Results Using This Chapter U
448. st mode refer to Swept List Frequency Sweep Hz on page 7 17 For moreinformation on making measurements with swept list mode refer to Using the Swept List Mode to Test a Device on page 1 65 1 Toset up a swept list measurement press SWEEP TYPE MENU EDIT LIST ADD 2 The frequency segments can be defined in any of the following terms start stop number of points power l F BW start stop step power l F BW e center span number of points power l F BW center span step power l F BW 3 When finished press DONE LIST TYPE SWEPT 5 9 Optimizing Measurement Results Increasing Sweep Speed Sweep Speed Related Errors IF delay occurs during swept measurements when the signal from the analyzer source is delayed in reaching the analyzer receiver because of an electrically long device The receiver has a narrow IF band pass filter that tracks the receiver frequency because the receiver is sweeping The delayed signal will be attenuated because the center of the internal IF filter has moved For most measurements swept list mode will be the optimum choice If there is any doubt about the effect of IF delay perform the following test 1 Set up the measurement using the swept list mode as in the previous procedure 2 Makethe measurement and savethe data trace to memory DATA S MEMORY DISPLAY DATA and MEMORY 3 Then switch to stepped list mode SWEEP TYPE MENU EDITLIST LIST TYPE STEPPED DONE Ifthereis no difference
449. stematic errors repeatable measurement variations in the test setup The analyzer measures known standard devices and uses the results of these measurements to characterize the system Measurement accuracy and system characteristics can be affected by the following factors Adapting to a different connector type or impedance Connecting a cable between the test device and an analyzer test port e Connecting any attenuator or other such device on the input or output of the test device If your test setup meets any of the these conditions the following system characteristics may be affected e amplitude at device input frequency response accuracy directivity crosstalk isolation Source match load match Calibrating for Increased Measurement Accuracy Calibration Considerations Calibration Considerations Measurement Parameters Calibration procedures are parameter specific rather than channel specific When a parameter is selected the instrument checks the available calibration data and uses the data found for that parameter For example if a transmission response calibration is performed for B R and an S44 1 port calibration for A R the analyzer retains both calibration sets and corrects whichever parameter is displayed Once a calibration has been performed for a specific parameter or input measurements of that parameter remain calibrated in either channel as long as stimulus values are coupled In the re
450. surement parameters If you change measurement parameters such that the instrument can no longer maintain the selected sweep time the analyzer will change tothe fastest sweep time possible Auto sweep time Auto sweep time continuously maintains the fastest sweep speed possi ble with the selected measurement parameters Sweep time refers only to the time that the instrument is sweeping and taking data and does not include the time required for internal processing of the data retrace time or band switching time A sweep speed indicator T is displayed on the trace for sweep times longer than 1 0 second For sweep ti mes equal to or faster than 1 0 second the f indicator appears in the status notations area at theleft of the analyzer s display Manual Sweep Time Mode When this modeis active the softkey label reads SWEEP TIME MANUAL This modeis engaged whenever you enter a sweep time greater than zero This mode allows you to select a fixed sweep time If you change the measurement parameters such that the current sweep time is no longer possible the analyzer will automatically increaseto the next fastest sweep time possible If the measurement parameters are changed such that a faster sweep time is possible the analyzer will not alter the sweep time whilein this mode Auto Sweep Time Mode When this mode is active the softkey label reads SWEEP TIME AUTO This modeis engaged whenever you enter 0 as a sweep time Auto sweep time c
451. surement Accuracy Calibrating Using Electronic Calibration ECal 5 f you need to calibrate with a second E Cal module connect one end of another DB25 cable to the connector on the PC interface unit labeled DB25 Interface to E Cal Module B Connect the other end of the DB25 cableto the parallel cable connector on the ECal module NOTE Why Use a Second ECal Module If the frequency span of the measurement that you set up earlier exceeds the span of a single ECal module you need to use another ECal module whose frequency range allows the rest of the measurement span to be calibrated The frequency range of the E Cal modules is listed in the General Information chapter of the 85097A Electronic Calibration System User s Guide 6 Using an RF cable or a microwave cable as appropriate connect one port of the E Cal module to test port 1 of the analyzer Refer to Figure 6 21 CAUTION RF ECal modules can be damaged if you apply excessive torque to the connectors Do not exceed the recommended torque indicated in the Electronic Calibration M odule Reference Guide part number 85091 90009 NOTE It is not critical which E Cal module port Port A or Port B is connected to the network analyzer test ports The network analyzer detects where each E Cal module port is connected and uses the appropriate module data If Port A is connected to Port 1 of the analyzer the calibration will be performed slightly faster 7 Using an RF cable or a m
452. surements do not require correction for all twelve errors Table 6 2 explains each correction and its uses Table 6 2 Purpose and Use of Different Error Correction Procedures Correction Procedure Corresponding Measurement Errors Corrected Standard Devices Response Transmission or reflection measurement when the highest accuracy is not required Frequency response Thru for transmission open or short for reflection Response amp Isolation Transmission of high insertion loss devices or reflection of high return loss devices Not as accurate as 1 port or 2 port correction Frequency response plus isolation in transmission or directivity in reflection Same as response plus isolation standard load 6 10 Calibrating for Increased Measurement Accuracy Procedures for Error Correcting Your Measurements Table 6 2 Purpose and Use of Different Error Correction Procedures Correction Procedure Corresponding Measurement Errors Corrected Standard Devices Enhanced Response and Enhanced Transmission or reflection Directivity source match and frequency Short open load and thru or ECal module Reflection measurement when response for improved accuracy is reflection Frequency desired Not as response source accurate as 2 port match and isolation calibration for transmission Enhanced reflection corrects for load mat
453. t 16 Press ISOLATION and select from the following two options L1 If you will be measuring devices with a dynamic range less than 90 dB press NOTE NOTE OMIT ISOLATION L1 If you will be measuring devices with a dynamic range greater than 90 dB follow these steps a Connect impedance matched loads to PORT 1 and PORT 2 Include the adapters that you would include for your device measurement If you will be measuring highly reflective devices such as filters use the test device connected to the reference plane and terminated with a load for the isolation standard Activate at least four times more averages than desired during the device measurement If loads can be connected to both port 1 and port 2 simultaneously then the following step can be performed using the DO BOTH FWD REV softkey Press RESUME CAL SEQUENCE ISOLATION FWD ISOL N ISOL N STD REVISOL N ISOL N STD ISOLATION DONE Return the averaging to the original state of the measurement and press RESUME CAL SEQUENCE 6 31 Calibrating for Increased Measurement Accuracy Full Two Port Error Correction 17 To compute the error coefficients press DONE 2 PORT CAL Theanalyzer displays the corrected measurement trace The analyzer also shows the notation Cor at theleft of the screen indicating that error correction is on NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotti
454. t i Jun 2888 15 47 32 Hi 11 Log 5 dBZREF 15 dB AT TT TETRA CENTER 1 400 000 666 GHz SPAN 3 488 000 aga GHz pa5197e Setting Up Limits for Ripple Testing This section instructs you on setting up the ripple test parameters You must set up the analyzer to check the DUT at the correct frequencies and compare the measured values against the maximum allowable ripple value for each frequency band To do this you set up individual frequency bands You definethe stop and start frequency and the maxi mum allowable ripple value of each frequency band You may set up as many as 12 frequency bands for testing ripple The frequency bands are combined in a list that is displayed while theripple frequency bands are being edited In this example we will create one ripple limit or frequency band that spans the entire pass band from 500 MHz to 3 0 GHz We will also create two additional frequency bands that when merged will span the pass band with tighter limits Using the Ripple Edit Menu we will create a ripple limits list on the analyzer that is similar tothe following table Table 1 4 Ripple Limits for Ripple Test Example Frequency Minimum Maximum Maximum Band Frequency Frequency Ripple 1 500 MHz 3 2 GHz 2 0 dB 2 500 MHz 1 85 GHz 1 3 dB 3 1 85 GHz 3 2 GHz 1 3 dB Notice that Frequency Band 1 overlaps in frequency the remaining fre
455. t Load Open Short Load Adapters For S41 For 55 pa587e 8 To measure the standard when the displayed trace has settled press OPEN The analyzer displays WAIT MEASURING CAL STANDARD during the standard measurement The analyzer underlines the OPEN softkey after it measures the standard 9 Disconnect the open and connect a short circuit to the test port 10 To measure the device when the displayed trace has settled press SHORT The analyzer measures the short circuit and underlines the SHORT softkey 11 Disconnec the short and connect an impedance matched load to the test port 6 23 Calibrating for Increased Measurement Accuracy Enhanced Frequency Response Error Correction 12 To measure the standard when the displayed trace has settled press LOADS select thetype of load you are using and then press DONE LOADS when the analyzer has finished measuring the load Noticethat the LOADS softkey is now underlined 13 To compute the reflection correction coefficients press STANDARDS DONE 14 To start the transmission portion of the correction press TRANSMISSION 15 M ake a thru connection between the points where you will connect your device under test as shown in Figure 6 7 NOTE Include any adapters or cables that you will havein the device measurement That is connect the standard device where you will connect your device under test NOTE Thethru in most calibration kits is defined with zero length
456. t can be grounded to e theanalyzer s chassis thefront panel binder post e theouter shell of the TEST SET I O INTERCONNECT connector e aground pin on the TEST SET I O INTERCONNECT connector pin 7 12 or 18 Refer toFigure 1 77 Pin C common on the external switch 8762B Option T24 must be connected to the test set interface pin 14 22 volt line Refer to Figure 1 77 Pin 2 on the external switch connects to pin 22 TTL 1 on the test set interface The TTL I O can control both of the external RF switches Both must be cascaded in parallel together Changing the TTL I O FWD from 7 to 6 will change the external RF switch state This changes the measurement capability from the network analyzer to the external test measurement device The TTL 1 0 FWD when changed from 7 to 6 will reverse the process 1 109 Making Measurements Using Test Sequencing Table 1 6 Test Set Interconnect Pin Designation Pin Number Pin Description Pin1 Pin2 Pin3 Pin4 Pin5 Pin 6 Pin 7 Pin 8 Pin9 Pin 10 Pin 11 Pin 12 Pin 13 Pin 14 Pin 15 Pin 16 Pin 17 Pin 18 Pin 19 Pin 20 Pin 21 Pin 22 Pin 23 Pin 24 Pin 25 No Connection NC Sweep delay holds off sweeps until test set has finished sweeping 85046A B and 85047B only Same as Test Sequence TTL OUT output BNC connector NC NC NC Ground Hi forward L ow reverse Follows the test port indicator NC Lstarttrig Not used Do not connect anything
457. t executing each line as you do so you can press the X key and scroll through the command list backwards 4 Todeletethe current command for example span value press 5 Toinsert a new value for example 75 MHz press 6 Press DONE SEQ MODIFY to exit the modify edit mode Clearing a Sequence from Memory 1 To enter the menu where you can dear a sequence from memory press MORE CLEAR SEQUENCE 2 Todear a sequence press the softkey of the particular sequence 1 101 Making Measurements Using Test Sequencing Changing the Sequence Title If you are storing sequences on a disk you should replace the default titles SEQ1 SEQ2 1 To select a sequence that you want to retitle press MORE TITLE SEQUENCE and select the particular sequence softkey The analyzer shows the available title characters The current title is displayed in the upper left corner of the screen 2 You can create a new file name in two ways e f you have an attached DIN keyboard you can press the f6 function key on the keyboard and type the new file name f you do not have an attached DIN keyboard press ERASE TITLE andturn the front panel knob to point to the characters of the new file name pressing SELECT LETTER as you stop at each character The analyzer cannot accept a title file name that is longer than eight characters Your titles must also begin with a letter and contain only letters and numbers 3 To complete th
458. t fundamental frequency for maximum frequency and harmonic mode Table 1 3 Maximum Fundamental Frequency using Harmonic Mode Maximum Fundamental Frequency Harmonic Measured 8753ES Option 011 8753ES Option 011 with Option 006 3 GHz 6 GHz 2nd Harmonic 1 5 GHz 3GHz 3rd Harmonic 1 0GHz 2 0 GHz Accuracy and input power Refer tothe Specifications and Characteristics chapter in the reference guide The maximum recommended input power and maximum recommended source power are related specifications Using power levels greater than the recommended values may cause undesired harmonics in the source and receiver The recommended power levels ensure that these harmonics are less than 45 dBc Usetest port power to limit the input power to your test device 1 58 Making Measurements Measuring Amplifiers Measuring Gain Compression Gain compression occurs when the input power of an amplifier is increased to a level that reduces the gain of the amplifier and causes a nonlinear increasein output power The point at which the gain is reduced by 1 dB is called the 1 dB compression point The gain compression will vary with frequency so it is necessary to find the worst case point of gain compression in the frequency band Once that point is identified you can perform a power sweep of that CW frequency to measure the input power at which the 1 dB compression occurs and the absolute power out in dBm at compression Th
459. t occur after trace math except smoothing and gating are identical for the data trace and the memory trace If smoothing or gating is on when a memory trace is saved this state is maintained regardless of the data trace smoothing or gating status If a memory trace is saved with gating or smoothing on these features can be turned on or off in the memory only display mode The actual memory for storing a memory trace is allocated only as needed The memory trace is cleared on instrument preset power on or instrument state recall If sweep mode or sweep range is different between the data and memory traces trace math is allowed and no warning message is displayed If the number of points in the two traces is different the memory trace is not displayed nor rescaled H owever if the number of points for the data traceis changed back to the number of points in the memory the memory trace can then be displayed If trace math or display memory is requested and no memory trace exists the message CAUTION NO VALID MEMORY TRACE is displayed To Save a Data Trace to the Display Memory Press DATA MEMORY to store the current active measurement data in the memory of the active channel The data trace is now also the memory trace You can usea memory trace for subsequent math manipulations Making Measurements Using Display Functions To View the Measurement Data and Memory Trace The analyzer default setting shows you the current m
460. t standards are used at each step of the calibration For example standard number 2 and 8 usually makes up the S A reflection class which for type N calibration kits are male and female shorts 7 56 Operating Concepts Modifying Calibration Kits Procedure The following steps are used to modify or define a user kit 1 Select the predefined kit to be modified This is not necessary for defining a new calibration kit Define the standards Define which type of standard it is Definethe electrical characteristics coefficients of the standard 3 Spedify the dass where the standard is to be assigned 4 Store the modified calibration kit Modify Calibration Kit Menu The MODIFY softkey in the cal kit menu accesses the modify calibration kit menu This leads in turn to additional series of menus associated with modifying calibration kits Thefollowing is a description of the softkeys located within this menu DEFINE STANDARD makes the standard number the active function and brings up the define standard menus Before selecting a standard a standard number must be entered This number 1 to 8 is an arbitrary reference number used to reference standards while specifying a class The standard numbers for the predefined calibration kits are as follows short m open m broadband load thru sliding load lowband load short f on OQ Ui A W N HH open f NOTE Although the numbering sequences ar
461. t up the segment for the upper stopband press ADD START STOP NUMBER of POINTS 8 To maximize the dynamic range in the stopband increasing the incident power and narrowing the IF bandwidth press MORE SEGMENT POWER SEGMENT IF BW RETURN DONE 9 Press DONE LIST FREQ SWEPT 1 68 Making Measurements Using the Swept List Mode to Test a Device Calibrate and Measure 1 Removethe DUT and perform a full two port calibration Refer to Chapter 6 Calibrating for Increased Measurement Accuracy 2 With the thru connected set the scale to autoscale to observe the benefits of using swept list mode Thesegments used to measure the stopbands have less noise thus maximizing dynamic range within the stopband frequencies The segment used to measure the passband has been set up for faster sweep speed with more measurement points Figure 1 54 Calibrated Swept List Thru Measurement CH1 Sg log MAG 03 dB REF 150 dB tal PRm Conr CENTER 900 000 000 MHz SPAN 500 000 000 MHz pa5111e 3 Reconnect the filter and adjust the scale to compare results with the first filter measurement that used a linear sweep In Figure 1 55 notice that the noise evel has decreased over 10 dB confirming that the noise reduction techniques in the stopbands were successful Also notice that the stopband noise in the third segment is slightly lower than in t
462. t your test device as shown in Figure 1 2 Figure 1 2 Device Connections for Measuring a Magnitude Response NETWORK ANALYZER pa53e 2 Press and choose the measurement settings For this examplethe measurement parameters are set as follows Trans FWD S21 B R AUTO SCALE Trans FWD S21 B R Scale Ref AUTO SCALE You may also want to select settings for the number of data points averaging and IF bandwidth 3 Removethe device and connect the power cables together thru and perform a response calibration using the following key presses Press CALIBRATE MENU RESPONSE THRU 1 7 Making Measurements Measuring Magnitude and Insertion Phase Response If the channels are coupled the default condition this calibration is valid for both channels 4 Reconnect your test device 5 To better view the measurement trace press Scale Ref AUTO SCALE 6 To locate the maxi mum amplitude of the device response as shown in Figure 1 3 press Marker Search SEARCH MAX Figure 1 3 Example Magnitude Response Measurement Results CH1 S214 log MAG 10 dB REF 50 dB 1 83 601 dB tal 139 5500 OGO MHz PRm cor MARKER 1 189 4 MHE A Ladies CENTER 134 000 O00 MHz SPAN 50 000 000 MHz pa5106e Measuring Insertion Phase Response 7 To view both the magnitude and phase response of the device as shown in Figure 1 4 press DUAL QUAD SETUP
463. ta format as well as a list of CITIFile keywords refer to the Understanding the CITIFile Data Format chapter in the reference guide S2P Data Format This format creates component data files that describe frequency dependent linear network parameters for 2 port components These files are assigned a file name with the suffix S and are only output that is they cannot be read in by the analyzers Up to two S2P files are saved S1 for channel 1 and S2 for channel 2 S2P files are not stored for channel 3 or channel 4 because the data would be redundant Each S2P file contains all four S parameter data An S2P fileis only output when the all of following conditions are met afull two port or TRL two port correction is turned on DATA ARRAY ON or DATA ONLY ON is selected using DEFINE DISK SAVE SAVE USING ASCII is selected Error corrected data CITI files are always saved along with S2P files 4 40 Printing Plotting and Saving Measurement Results Saving Measurement Results The template for component data files is as follows comment line frequency units parameter format Rn data line data line where indicates that all following on this lineis a comment indicates that entries following on this line are parameters that are being specified frequency units GHz MHz kHz Hz parameter S for S parameters format DB for dB magnitude and angle in degrees MA for linear magnitude and angl
464. tage signal for service purposes Figure 7 13 Real Format CH1 AUX Re 5 u s REF OU 19 476 U LJ i START O e Cw 1 DOD DOO 000 MHz STOP 100 pg6173 c Imaginary Format The IMAGINARY softkey displays only the imaginary reactive portion of the measured data on a Cartesian format This format is similar tothe real format except that reactance data is displayed on the trace instead of resistive data Group Delay Principles For many networks the amount of insertion phase is not as important as the linearity of the phase shift over a range of frequencies The analyzer can measurethis linearity and express it in two different ways directly as deviation from linear phase or as group delay a derived value Group delay is the measurement of signal transmission time through a test device It is defined as the derivative of the phase characteristic with respect to frequency Sincethe derivative is basically the instantaneous slope or rate of change of phase with respect to frequency a perfectly linear phase shift results in a constant slope and therefore a constant group delay See Figure 7 14 7 29 Operating Concepts Analyzer Display Formats Figure 7 14 Constant Group Delay Frequency Phase pg6182 c Note however that the phase characteristic typically consists of both linear and higher order deviations from linear components The linear co
465. te differently in sequence 1 104 feedthrough RF 2 45 file deleting 4 51 index numbers 4 44 recalling 4 52 renaming 4 52 sequential CSV naming of 4 44 to delete all 4 51 filter characteristics 1 66 finiteimpulse width or risetime 3 27 fixed IF mixer adjustments tuned receiver mode 2 24 fixed IF mixer measurements 2 24 addressing and configuring two Sources 2 27 calling the next measurement sequence 2 27 decrementing the loop counter 2 29 frequency list sweep of 26 points 2 26 incrementing the source frequencies 2 29 initializingloop counter valueto 26 2 27 labeling the screen 2 30 presetting the instrument 2 25 Index 3 Index prompting user to connect mixer test setup 2 26 response calibration 2 26 sequence 1 setup 2 24 sequence 2 setup 2 29 taking data 2 29 tuned receiver mode 2 26 fixed markers 1 29 fixtures 6 50 designing your own fixture 6 51 flat limit lines 1 72 floppy disk what you can save 4 35 form feed sequence 4 24 sending to the printer 4 24 format 7 9 format arrays 7 9 format markers polar 1 32 formats analyzer display 7 24 formatting a disk 4 53 forward stepping in edit mode 1 105 forward transform measurements 3 22 demodulating the results of the forward transform 3 23 forward transform range 3 24 interpreting the forward transform horizontal axis 3 23 interpreting the forward transform vertical axis 3 22 forward transform mode 3 4 for
466. ted with it Conversely if you choose to save the format array your modification of the recalled measurement will be limited by all the processes that are associated with that measurement result H owever the format array is appropriate if you want toretrieve data traces that look likethe currently displayed data Define Save Modification Flexibility During Recall Raw Data Array Most Data Array Medium Format Array Least You can also save data only This is saved to disk with default file names DATAOOD1 to DATA31D1 for channel 1 DATAOOD2 to DATA31D2 for channel 2 DATAOOD3 to DATA31D3 for channel 3 DATAOOD4 to DATA31D4 for channel 4 However these files are not instrument states and cannot be recalled 4 37 Printing Plotting and Saving Measurement Results Saving Measurement Results Figure 4 13 Data Processing Flow Diagram O B 9 o L DIGITAL mc SAMPLER IF R O ADC FILTER RATIO CORRECTION AUX INO O Lp SWEEP SWEEP RAW DATA ERROR DATA TRACE AVERAG ING ARRAYS CORRECTION ARRAYS MATH ERRO MEMORY ROR COEFFICIENT ARRAYS ARRAY L GATING ELECTRICAL CONVERSION TRANSFORM FORMAT OPT 010 DELAY OPT 010 FORMAT ARRAYS DMA OFFSET DISPLAY LCD SCALE MEMORY SMOOTHING
467. tep transmission response vertical axis 3 20 measuring separate transmission paths through the test device using low pass impulse mode 3 20 measuring small signal transient response using low pass step 3 19 transmission measurements using bandpass mode 3 14 interpreting the bandpass transmission response horizontal axis 3 14 interpreting the bandpass transmission response vertical axis 3 14 transmission measurements response and isolation error correction 6 17 Index 11 Index transmission measurements response error correction 6 14 transmission response measurements making 3 5 TRL calibration performing 6 54 TRL error correction assigning standards to various TRL classes 6 53 label the calibration kit 6 53 label the classes 6 53 performingtheTRL calibration 6 54 TRL error correction 6 52 creating a user defined TRL calibration kit 6 52 TRL options 7 75 TRL terminology 7 67 TRL error model 7 67 TRL LRM calibration 7 66 fabricating and defining calibration standards for TRL LRM 7 72 how TRL LRM works 7 67 improving raw source match and load match for TRL LRM calibration 7 70 isolation 7 68 source match and load match 7 69 TRL calibration procedure 7 71 TRL options 7 75 TRL standards requirements 7 71 TRL terminology 7 67 TRL error model 7 67 TRL LRM two port calibration 7 55 TRM error correction 6 56 assigning standards to various TRM classes 6 57 creating
468. ter This instrument protects against finger access to hazardous parts within the enclosure Safety and Regulatory Information Safety Considerations Compliance with German FTZ E missions Requirements This network analyzer complies with German FTZ 526 527 Radiated E missions and Conducted E mission requirements Compliance with German Noise Requirements This is to dedarethat this instrument is in conformance with the German Regulation on Noise Declaration for Machines Laermangabe nach der Maschinenlaermrerordung 3 GSGV Deutschland Acoustic Noise Emission Geraeuschemission L pA lt 70 dB Lpa lt 70 dB Operator Position am Arbeitsplatz Normal Operation normaler Betrieb per ISO 7779 nach DIN 45635 t 19 Compliance with Canadian EMC Requirements This ISM device complies with Canadian I CE 001 Cet appareil ISM est conforme a la norme NMB du Canada Safety and Regulatory Information Declaration of Conformity Declaration of Conformity DECLARATION OF CONFORMITY According to ISO IEC Guide 22 and CEN CENELEC EN 45014 Manufacturer s Name Agilent Technologies Inc Manufacturer s Address 1400 Fountaingrove Parkway Santa Rosa CA 95403 1799 USA Declares that the products Product Name Network Analyzer Model Number 8753ES 8753ET Product Options This declaration covers all options of the above products Conform to the following product specifications EMC IEC 613
469. ter of the programmer s guide 4 35 Printing Plotting and Saving Measurement Results Saving an Instrument State Saving an Instrument State 1 Press Save Recall SELECT DISK and select one of the storage devices 1 INTERNAL MEMORY 1 INTERNAL DISK 1 EXTERNAL DISK connect an external disk drive to the analyzer s GPIB connector and configure as follows a Connect an external disk drive to the analyzer s GPIB connector and configure as follows b Press DISK UNIT NUMBER and enter the drive where your disk is located followed by x1 C If your storage disk is partitioned press VOLUME NUMBER and enter the volume number where you want to store the instrument state file d Press SET ADDRESSES ADDRESS DISK e Enter the GPIB address of the peripheral if the default address is incorrect default 00 Follow the entry by pressing x1 f Press and select one of the following SYSTEM CONTROLLER allows the analyzer to control peripherals directly TALKER LISTENER allows the computer controller to be involved in all peripheral access operations USE PASS CONTROL allows you to control the analyzer over GPIB and also allows the analyzer to take or pass control 2 Press Save Recall SAVE STATE The analyzer saves the state in the next available register if you are saving to internal memory or saves the state to disk Although one file is shown to represent an instrument state on the analyze
470. ter or an up converter measurement is being performed Itisimportant to keep in mind that in the setup diagrams of the frequency offset mode the analyzer s source and receiver ports are labeled according to the mixer port to which they are connected n a down converter measurement wherethe DOWN CONVERTER softkey is selected the notation on the analyzer s setup diagram indicates that the analyzer s source frequency is labeled RF connecting to the mixer RF port and the analyzer s receiver frequency is labeled IF connecting to the mixer IF port Because the RF frequency can be greater or less than the set LO frequency in this type of measurement you can select either RF gt LO or RF LO 2 8 Making Mixer Measurements Measurement Considerations Figure 2 7 Down Converter Port Connections NETWORK ANALYZER pe521e n an up converter measurement where the UP CONVERTER softkey is selected the notation on the setup diagram indicates that the analyzer s source frequency is labeled IF connecting to the mixer IF port and the analyzer s receiver frequency is labeled RF connecting to the mixer RF port Because the RF frequency can be greater or less than the set LO frequency in this type of measurement you can select either RF gt LO or RF LO Figure 2 8 Up Converter Port Connections NETWORK ANALYZER pa522e Making Mixer Measurements Measurement Considerations Frequency Offset Mode Operation This mode of ope
471. ter the destination sequence 1 111 Making Measurements Using Test Sequencing Loop counter decision making The analyzer has a numeric register called a loop counter The value of this register can be set by a sequence and it can be incriminated or decremented each time a sequence repeats itself The decision making commands IF LOOP COUNTER 0 and IF LOOP COUNTER lt 0 jump to another sequence if the stated condition is true When entered into the sequence these commands require you to enter the destination sequence Either command can jump to another sequence or restart the current sequence As explained in Embedding the Value of the Loop Counter in a Title on page 1 105 the loop counter value can be appended to a title This allows customized titles for data printouts or for data files saved to disk 1 112 Making Measurements Using Test Sequencing to Test a Device Using Test Sequencing to Test a Device Test sequencing allows you to automate repetitive tasks As you make a measurement the analyzer memorizes the keystrokes Later you can repeat the entire sequence by pressing a single key This section contains the following example sequences e Cascading Multiple Example Sequences Loop Counter Example Sequence on page 1 114 Generating Files in a Loop Counter Example Sequence on page 1 115 Limit Test Example Sequence on page 1 117 Cascading Multiple Example Sequences By cascading test sequences you
472. ter up to 12 frequency bands for maximum ripple testing 1 To access the ripple test edit menu press EDIT RIPL LIMIT 2 Create a new frequency band by pressing ADD 3 Set the lower frequency value of the frequency band by pressing a MINIMUM FREQUENCY b the numeric keys indicating the minimum frequency value of the frequency band c the appropriate frequency key either CGn M or Km 4 Set the upper frequency value of the frequency band by pressing a MAXIMUM FREQUENCY b the numeric keys indicating the maximum frequency value of the frequency band c the appropriate frequency key either Gmn M or k m 5 Set the maximum allowable ripple amplitude value of the frequency band by pressing a MAXIMUM RIPPLE b the decibel value of the frequency band s maximum allowable ripple c GD 6 Repeat steps 2 through 5 for additional frequency bands to be tested for maximum ripple 7 After you have added all of the new frequency bands return to the ripple test menu by pressing DONE 1 84 Making Measurements Using Ripple Limits to Test a Device Deleting Existing Frequency Bands Frequency band limits may be deleted for testing theripple This procedure guides you through deleting existing frequency band limits You may delete individual frequency bands or delete all of the frequency bands from the list 1 To access the ripple test edit menu press EDIT RIPL LIMIT 2 Select the first frequency band as an exampl
473. terconnect on the rear panel was originally intended for use solely with the HP Agilent 85046A B and HP Agilent 85047B external S parameter test sets Sincethe introduction of the 8753D a network analyzer with an internal test set this test set O port has become a general purpose control port for a variety of external devices such as the K 36 or K 39 test adapters and Option 014 configurations Refer Table 1 6 on page 1 110 for the definition of each pin of the test set 1 O connector CAUTION 22 volts is available on the TESTSET 1 O connector Be careful not to connect this to a printer port or to sensitive electronic equipment This connector with the limit output TTL OUT and TESTSET I O outputs can also be used with part handlers to provide control interface TheTESTSET I O bits areset using the TESTSET I O FWD and TESTSET I O REV keys under the TTL I O TTL OUT keys The values of the outputs pins 11 22 and 23 are described in Table 1 6 The value changes with the test port soif the external control is required for both test port directions the settings must be made under both TESTSET I O FWD and TESTSET I O REV This capability can be used to set different external conditions in a test requiring changes between the forward and reverse measurements as might be needed in a high power test for example 1 106 Making Measurements Using Test Sequencing TTL 1 O Menu This menu can be accessed by pressing TTL I O in the Sequencing
474. the transmission medium under test must be entered intothe electrical length equation 3 32 Making Time Domain Measurements Resolution For example a cable with a teflon dielectric 0 7 relative velocity factor measured under the conditions stated above has a fault location measurement response resolution of 0 45 centi meters This is the maximum fault location response resolution Factors such as reduced frequency span greater frequency domain data windowing and a large discontinuity shadowing the response of a smaller discontinuity all act to degrade the effective response resolution Figure 3 24 illustrates the effects of response resolution The solid line shows the actual reflection measurement of two approximately equal discontinuities the input and output of an SMA barrel The dashed line shows the approximate effect of each discontinuity if they could be measured separately Figure 3 24 Response Resolution CH1 S11 lin MAG 2 mU REF 4 mU hp N rN id N T D CH1 START 570 ps STOP 2 505 ns pg682d While increasing the frequency span increases the response resolution keep the following points in mind Thetime domain response noise floor is directly related to the frequency domain data noise floor Because of this if the frequency domain data points are taken at or below the measurement noise floor the time domain measurement noise floor is degra
475. the ECal calibration selection is made the network analyzer performs the calibration 4 f you selected the manual thru calibration option when the prompt is displayed remove the E Cal module from the setup and connect the manual thru the two test ports connected together as shown in Figure 6 22 6 64 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal Figure 6 22 Manual Thru Setup NETWORK ANALYZER Parallel Port Connection Second PC Interface ECal Module First Unit ECal Module PC Interface Power Supply to AC Power pl504ets 5 After you connect the manual thru press CONTINUE ECal to complete the manual thru portion of the ECal 6 If you are calibrating using two ECal modules a prompt is displayed directing you to remove the first module and connect the second module Follow this prompt as shown in Figure 6 23 Figure 6 23 Connect the Second ECal Module NETWORK ANALYZER Parallel Port Connection Second ECal Module 1 1 PC Interface Unit PC Interface Power Supply First ECal Module to AC Power pl506ets 6 65 Calibrating for Increased Measurement Accuracy Calibrating Using Electronic Calibration ECal 7 After you connect the second E Cal module press CONTINUE ECal to continue the ECal 8 Repeat steps 4 and 5 if you selected to calibrate using the manual thru option 9 Review the displayed c
476. the harmonic power Theanalyzer shows the fundamental frequency value on the display H owever a marker in the active entry area shows the harmonic frequency in addition to the fundamental If you use the harmonic mode the annotation H 2 or H 3 appears on the left hand side of the display The measured harmonic cannot not exceed the frequency limitations of the network analyzer s receiver 1 57 Making Measurements Measuring Amplifiers Coupling Power Between Channels land 2 COUPLED PWR ON off is intended to be used with the D2 D1toD2 on OFF softkey You can usethe D2 D1 to D2 function in harmonic measurements where the analyzer shows the fundamental on channel 1 and the harmonic on channel 2 D2 D1 to D2 ratios the two showing the fundamental and the relative power of the measured harmonic in dBc You must uncouple channels 1 and 2 for this measurement using the COUPLED CHAN ON off softkey set to OFF to allow alternating sweeps After uncoupling channels 1 and 2 you may want to change the fundamental power and see the resultant change in relative harmonic power in dBc COUPLED PWR ON off allows you to change the power of both channels simultaneously even though they are uncoupled in all other respects Frequency Range The frequency range is determined by the upper frequency range of the instrument or system 3 or 6 GHz and by the harmonic being displayed The 6 GHz operation requires an 8753E S Option 006 Table 1 3 shows the highes
477. the modulation separately The window menu indudes the following softkeys to control the demodulation feature DEMOD OFF isthenormal preset state in which both the amplitude and phase components of any test device modulation appear on the display AMPLITUDE displays only the amplitude modulation as illustrated in Figure 3 19a PHASE displays only the phase modulation as shown in Figure 3 19b 3 23 Making Time Domain Measurements Transforming CW Time Measurements into the Frequency Domain Figure 3 19 Separating the Amplitude and Phase Components of Test Device I nduced Modulation CH1 B log MAG 10 dB REF 50 dB i 20 829 dB CH1 B log MAG 10 dB EF 50 dB 0006 dB 0 Hz va ta CH1 CENTER O Hz Cw 250 000 000 MHz SPAN 2 KHZ CH4 CENTER O Hz CW 250 000 000 MHz SPAN 2 kHz a Amplitude Modulation Component b Phase Modulation Component pg6188 c Forward Transform Range In theforward transform from CW timeto the frequency domain rangeis defined as the frequency span that can be displayed before aliasing occurs and is similar to range as defined for time domain measurements n the range formula substitute time span for frequency span Number of points 1 Range time span 201 1 Range ee 200 x 10 Range 1000 Hertz For the example a 201 point CW time
478. thru TRL reflect TRL line or match The number of standard classes required depends on the type of calibration being performed and is identical to the number of error terms corrected A response calibration requires only one dass and the standards for that class may include an open or short or thru A 1 port calibration requires three classes A full 2 port calibration requires 10 dasses not induding two for isolation 7 62 Operating Concepts Modifying Calibration Kits The number of standards that can be assigned to a given class may vary from none class not used to one simplest class to seven When a certain class of standards is required during calibration the analyzer will display the labels for all the standards in that class except when the class consists of a single standard This does not however mean that all standards in a class must be measured during calibration Unless band limited standards are used only a single standard per class is required NOTE It is often simpler to keep the number of standards per class to the bare minimum needed often one to avoid confusion during calibration Each class can be given a user definable label as described under label class menus Standards are assigned to a dass simply by entering the standard s reference number established while defining a standard under a particular dass The following is a description of the softkeys locate
479. tion ssseeeeeeeee hn 2 10 LO Frequency Accuracy and Stability auc doe Red Ede P EE e 2 10 Power Meter CallbEat OU 4 sad eee Geo eo REE E ER ROLE IC FCR DR ee awe sR 2 10 Conversion Loss Using the Frequency Offset Mode 0 ccc eee eee ees 2 11 Setting Measurement Parameters for the Power Meter Calibration 2 12 Performing a Power Meter Source Calibration Over the RF Range 2 12 Setting the Analyzer to Make an R Channel Measurement 00 cee e eee 2 15 vi Contents High Dynamic Range Swept RF IF Conversion Loss 0020 cece eee 2 18 Set Measurement Parameters for the IF Range 0 002 cece eee eee 2 18 Perform a Power Meter Calibration Over the IF Range 0 eeeee eens 2 18 Perform a Receiver Calibration Over the IF Range 0c eee e eee eee 2 20 Set the Analyzer tothe RF Frequency Range 00c cece eee 2 21 Perform a Power Meter Calibration Over the RF Range 0 eeeae reese 2 21 Perform the High Dynamic Range Measurement s s s 0 00 cee eens 2 22 Fixed IF Mixer Measurements 24 3 ic0008 240 bbe eee dde DASE DEES oO dE DE EEE DORE OS 2 24 Tuned Receiver Mode sacs aT eH rniii ike ese h eds i ehe TERR ESTO Rd CdoE ERR 2 24 SOquence L SOUS orequpkx aid4riqePEPE r PTebpr erefre qe4T TEpP PRPRQ pedsaseientads 2 24 Sequence SAUD sant ciee ident ad SERRE PER RO EE Eee RET eh ete RR dr d NEA 2 29 Phase or Group Delay Measure
480. tion A poorly measured isolation dass can actually degrade the overall measurement performance If you arein doubt of the isolation measurement quality you should omit the isolation portion of this procedure NOTE If loads can be connected to both port 1 and port 2 simultaneously then the following measurement can be performed using the DO BOTH FWD REV softkey 10 Connect a load to PORT 2 and press REV ISOL N ISOL N STD 11 Connect the load to PORT 1 and press FWD ISOL N ISOL N STD ISOLATION DONE 12 You may repeat any of the previous steps Thereis no requirement to goin the order of steps When the analyzer detects that you have made all the necessary measurements the message line will show PRESS DONE IF FINISHED WITH CAL Press DONE TRL LRM Themessage COMPUTING CAL COEFFICIENTS Will appear indicating that the analyzer is performing the numerical calculations of error coefficients 6 54 Calibrating for Increased Measurement Accuracy Calibrating for Non Coaxial Devices NOTE You can save or store the measurement correction to use for later measurements Refer to Chapter 4 Printing Plotting and Saving Measurement Results for procedures 13 Connect the device under test The device S parameters are now being measured 6 55 Calibrating for Increased Measurement Accuracy LRM Error Correction LRM Error Correction Create a User Defined LRM Calibration Kit In
481. tion Calibration Isolation calibration can be omitted for most measurements except where high dynamic range is a consideration Use the following guidelines When the measurement requires a dynamic range of Lessthan 90 dB Omit isolation calibration for most measurements Calibrating for Increased Measurement Accuracy Calibration Considerations e 90to 100 GB Isolation calibration is recommended with test port power greater than 0 dBm For this isolation calibration averaging should be turned on with an averaging factor at least four times the measurement averaging factor For example use an averaging factor of 16 for theisolation calibration and then reduce the averaging factor to four for the measurement after calibration Greater than 100 dB Same as 90 to 100 dB but alternate mode should be used See To View a Single Measurement Channel on page 5 12 Saving Calibration Data You should save the calibration data either in the internal non volatile memory or on a disk If you do not save it it will be lost if you select another calibration procedure for the same channel or if you change stimulus values Instrument preset power on and instrument state recall will also dear the calibration data Restarting a Calibration f you interrupt a calibration to go to another menu such as averaging you can continue the calibration by pressing the RESUME CAL SEQUENCE softkey in the correction menu The Calibration Standards
482. tly zero length thru or with a short length of transmission line non zero length thru and the transmission frequency response and port match are measured in both directions by measuring all four S parameters For the reflect step identical high reflection coefficient standards typically open or short circuits are connected to each test port and measured Sj and S32 For the line step a short length of transmission line different in length from thethru is inserted between port 1 and port 2 and again the frequency response and port match are measured in both directions by measuring all four S parameters In total ten measurements are made resulting in ten independent equations H owever the TRL error model has only eight error terms to solve for The characteristic impedance of the line standard becomes the measurement reference and therefore has to be assumed ideal or known and defined precisely At this point the forward and reverse directivity Epp and Epp transmission tracking Ef and Ezp and reflection tracking Ege and Err terms may be derived from the TRL error terms This leaves the isolation Exp and Exp source match Esp and Esg and load match E p and E pr terms to discuss Isolation Two additional measurements are required to solve for the isolation terms Exp and Exp Isolation is characterized in the same manner as the Full 2 port calibration Forward and reverse isolation are measured as theleakage
483. to the selected format This indudes group delay calculations These formats are often easier to interpret than the complex number representation Polar and Smith chart formats are not affected by the scalar formatting It is impossible to recover the complex data after formatting as shown in Figure 7 2 Smoothing This noise reduction technique smoothes noise on the trace Smoothing is also used to set the aperture for group delay measurements When smoothing is on each point in a sweep is replaced by the moving average value of several adjacent formatted points The number of points included depends on the smoothing aperture which can be selected by the user The effect is similar to video filtering If data and memory are displayed smoothing is performed on the memory trace only if smoothing was on when data was stored into memory Format Arrays The data processing results are now stored in the format arrays Notice that the marker values and marker functions are all derived from the format arrays in Figure 7 2 Limit testing is also performed on the formatted data The format arrays are accessible via GPIB Offset and Scale These operations prepare the formatted data for display This is wherethe reference line position reference line value and scale calculations are performed as appropriate to the format Display Memory The display memory stores the display image for presentation on the analyzer The information stored in
484. to uncouple the marker stimulus values for the display channels This allows you to control the marker stimulus values independently for each channel Figure 1 19 Example of Coupled and Uncoupled Markers CH1 Spy log MAG 18 dB REF 5 dB Z 23 423 dB CHi Sg log MAG 18 dB REF 50 dB 2 23 422 dB 134 42 sdi MHz h 134 42 sdi MHz CH2 82 log MAG 19 dB REF 58 dB 2 23 423 dB __ MARKER Z bo MAPA pump Mw START 116 508 000 MHz STOP 161 500 008 MHz START 116 508 020 MHz STOP 151 500 aaa MHz pg6235 1 31 Making Measurements Using Markers To Use Polar Format Markers Theanalyzer can display the marker value as magnitude and phase or as a real imaginary pair LIN MKR gives linear magnitude and phase LOG MKR gives log magnitude and phase Re Im gives the real value first then the imaginary value You can use these markers only when you are viewing a polar display format The format is available from the key NOTE For greater accuracy when using markers in the polar format it is recommended to activate the discrete marker mode Press MKR MODE MENU MARKERS DISCRETE 1 To access the polar markers press POLAR MARKER MODE MENU POLAR MKR MENU 2 Select the type of polar marker you want from the following choices Choose LIN MKR if you want to
485. topping a sequence 1 99 storing a sequence on a disk 1 103 using to test a device 1 113 text file saving measurements as a 4 43 thru manual 6 62 time delay decreasing 5 8 time domain bandpass mode 3 4 3 12 adjusting the relative velocity factor 3 12 reflection measurements using bandpass mode 3 12 transmission measurements using bandpass mode 3 14 time domain low pass impulse mode 3 4 time domain low pass mode 3 15 fault location measurements using low pass 3 18 minimum allowable stop frequencies 3 16 reflection measurements in time domain low pass 3 16 setting frequency range for time domain low pass 3 15 transmission measurements in time domain low pass 3 19 time domain low pass step mode 3 4 time domain measurements introduction 3 3 forward transform mode 3 4 time domain bandpass mode 3 4 time domain low pass impulse mode 3 4 time domain low pass step mode 3 4 time stamp 4 31 title 1 105 title display 1 11 titling the displayed measurement 4 30 to produce a time stamp 4 31 trace math operation 7 8 trace noise reducing 5 15 tracking 7 40 tracking the amplitude 1 41 tracking amplitude and phase 2 36 transform 7 9 transforming CW time measurements into the frequency domain 3 22 forward transform measurements 3 22 transmission measurements in time domain low pass 3 19 interpreting the low pass step transmission response horizontal axis 3 20 interpreting the low pass s
486. transmission lines are relatively easy to fabricate in a microstrip for example the impedance of these lines can be determined from the physical dimensions and substrate s dielectric constant TRL Error Model Figure 7 43 Functional Block Diagram for a 2 Port Error Corrected Measurement System 8 Error Terms pb6120d 7 67 Operating Concepts TRL LRM Calibration For the analyzer TRL 2 port calibration a total of 10 measurements are made to quantify eight unknowns not including the two isolation error terms Assume the two transmission leakage terms Exe and Exp are measured using the conventional technique The eight TRL error terms are represented by the error adapters shown in Figure 7 43 Although this error model is slightly different from the traditional Full 2 port 12 term model the conventional error terms may be derived from it For example the forward reflection tracking Egg is represented by the product of 19 and 94 Also notice that the forward source match E sc and reverse load match E n are both represented by 11 while the reverse source match E sg and forward load match E c are both represented by 55 In order to solve for these eight unknown TRL error terms eight linearly independent equations are required The first step in the TRL 2 port calibration process is the same as the transmission step for a Full 2 port calibration For the thru step the test ports are connected together direc
487. ts number of points 1 Measurement range frequency span Hz For example Measurement 201 points Frequency Span 1 MHz to 2 001 GHz Frequency Spacing AF 10MHz 1 number of points 1 Range eo E eet A frequency span 1 ag 201 1 Range I 9 10x10 2x10 Range 100 x 10 seconds Electrical Length range x the speed of light 3 x 10 ElectricalLength 100 x 0 s x 3x 10 8 M ElectricalLength 30 meters 3 30 Making Time Domain Measurements Range In this example the range is 100 ns or 30 meters electrical length To prevent the time domain responses from overlapping the test device must be 30 meters or less in electrical length for a transmission measurement 15 meters for a reflection measurement The analyzer limits the stop time to prevent the display of aliased responses To increase the ti me domain measurement range first increase the number of points but remember that as the number of points increases the sweep speed decreases Decreasing the frequency span also increases range but reduces resolution 3 31 Making Time Domain Measurements Resolution Resolution Two different resolution terms are used in the time domain response resolution rangeresolution Response Resolution Time domain response resolution is defined as the ability to resolve two closel y spaced responses or a measure of how close two respo
488. ty resistive capacitive or inductive that is present Low pass provides the best resolution for a given bandwidth in the frequency domain It may be used to give either the step or impulse response of the test device Thelow pass mode is less general purpose than the bandpass mode because it places strict limitations on the measurement frequency range The low pass mode requires that the frequency domain data points are harmonically related from dc to the stop frequency That is stop n x start where n number of points For example with a start frequency of 30 kHz and 101 points the stop frequency would be 3 03 MHz Sincethe analyzer frequency range starts at 30 kHz the dc frequency response is extrapolated from the lower frequency data The requirement to pass dc is the same limitation that exists for traditional TDR Setting the Frequency Range for Time Domain Low Pass Before a low pass measurement is made the measurement frequency range must meet the stop n x start requirement previously described The SET FREQ LOWPASS softkey performs this function automatically the stop frequency is set dose to the entered stop frequency and the start frequency is set equal to stop n If thelow end of the measurement frequency range is critical it is best to calculate approximate values for the start and stop frequencies before pressing SET FREQ LOWPASS and calibrating This avoids distortion of the measurement results To see an example s
489. ty error will add with the true reflected signal from the device causing an error in the measured data Overall directivity is the limit to which a device s return loss or reflection can be measured Therefore it is important to have good directivity to measure low reflection devices For example a coupler has a 7 mm connector and 40 dB directivity which is equivalent to a reflection coefficient of p 0 01 directivity in dB 20 log p Suppose we want to connect to a device with an SMA male connector We need to adapt from 7 mm to SMA If we choose a precision 7 mm to SMA adapter with a SWR of 1 06 which has p 0 03 the overall directivity becomes p 0 04 or 28 dB However if we use two adapters to dothe same job the reflection from each adapter adds up to degrade the directivity to 17 dB The last example shown in Figure 6 20 uses three adapters that shows an even worse directivity of 14 dB It is dear that a low SWR is desirable to avoid degrading the directivity of the system 6 49 Calibrating for Increased Measurement Accuracy Making Non Coaxial Measurements Making Non Coaxial Measurements Non coaxial on wafer measurements present a unique set of challenges for error correction in the analyzer e Thedose spacing between the microwave probes makes it difficult to maintain a high degree of isolation between the input and the output Thetype of device measured on wafer is often not always a simple two port t may b
490. type when external source is activated the warning message CHANGED TO CW TIME MODE Will appear on the display External Source Requirements The external source mode has spectral purity and power input requirements which are described in the specifications and characteristics chapter of the reference guide CaptureRange n either automatic or manual mode you can enter the frequency of the external CW signal usingthe CWFREQ softkey located under the Stimulus key The actual signal must be within a certain frequency capture range as shown in Table 7 3 Table 7 3 8753E S Option 011 External Source Capture Ranges Mode CW Frequency Capture Range Automatic lt 50 MHz 5 MHz of nominal CW frequency gt 50 MHz 10 of nominal CW frequency Manual All 0 5 to 5 MHz of nominal CW frequency If theincoming signal is not within the capture range the analyzer will not phaselock correctly Locking onto a signal with a frequency modulation component Although the analyzer may phase lock onto a signal that has F M it may not accurately show the signal s amplitude The accuracy of such measurements depends greatly on the IF bandwidth you choose Use the widest IF bandwidth available 3 kHz if this problem occurs Tuned Receiver Mode In the tuned receiver mode the analyzer s receiver operates independently of any signal source This mode is not phase locked and functions in all sweep types The analyzer tunes the re
491. u change any of the following parameters you will invalidate the correction and the analyzer will switch the correction off unless the interpolated error correction feature is activated frequency range e number of points e sweep type The error correction quality may be degraded Cor changes to cA if you change the following stimulus state parameters Sweep time System bandwidth output power If correction is turned off or shows cA the original stimulus state can be recalled by first turning interpolation off INTERPOL ON off and toggling correction off and then on CORRECTION ON off Calibrating for Increased Measurement Accuracy Procedures for Error Correcting Your Measurements Procedures for Error Correcting Your Measurements This section has example procedures or information on the following topics e frequency response correction frequency response and isolation correction e enhanced frequency response correction with enhanced reflection error correction one port reflection correction full two port correction TRL LRM correction power meter measurement calibration procedure NOTE Types of Error Correction If the channels are uncoupled you must make a correction for each channel Several types of error correction are available that remove from one to twelve systematic errors The full 2 port correction effectively removes all twelve correctable systematic errors Some mea
492. u must have an S parameter test set connected to your analyzer 1 49 Making Measurements Characterizing a Duplexer Figure 1 40 Duplexer Connections Testset I O NETWORK ANALYZER Test Adapter Duplexer pad7e 3 Set up channel 1 for the Tx Ant stimulus parameters start stop frequency power level IF bandwidth In this example a wide frequency range that covers both the Tx Ant and Ant Rx parameters has been chosen 4 Uncouple the primary channels from each other and then press and toggle COUPLED CH on OFF to OFF 5 Press System CONFIGURE MENU USER SETTINGS 6 Set up the desired mode e For K36 mode toggle K36 MODE on OFF to ON Then press SELECT TX ANT For K39 mode toggle K39 MODE on OFF toON Then press SELECT PORTS 1 3 7 Perform a full two port calibration on channel 1 refer to Chapter 6 Calibrating for Increased Measurement Accuracy if necessary NOTE Make sure you connect the standards to the Tx port of the test adapter or a cable attached to it for FORWARD calibrations and tothe Ant port for REVERSE calibrations 8 Save the instrument state by pressing SAVE STATE 9 Press Chan 2 10 Set up channel 2 for the Ant Rx stimulus parameters In this example a wide frequency range that covers both the Tx Ant and Ant Rx parameters has been chosen 1 50 Making Measurements Characterizing a Duplexer 11 Set up control of the test adapter sothat channels 2 and 4 are Rx
493. u two choices for a two graticule display Channels 1 and 2 overlaid in the top graticule and channels 3 and 4 are overlaid in the bottom grati cule Channels 1 and 3areoverlaid in thetop graticule and channels 2 and 4 areoverlaid in the bottom graticule When SPLIT DISP 4X is selected CHANNEL POSITION gives you two choices for a four graticule display Channels 1 and 2 arein separate graticules in the upper half of the display channels 3 and 4 arein separate graticules in the lower half of the display e Channels 1 and 3 are in the upper half of the display channels 2 and 4 are in the lower half of the display Making Measurements Using Display Functions 4 Param Displays Softkey The 4PARAM DISPLAYS menu does two things provides a quick way to set up a four parameter display gives information for using softkeys in the menu Figure 1 11 shows the first 4 PARAM DISPLAYS screen Six setup options are described with softkeys SETUP A through SETUPF SETUPA isafour parameter display where each channel is displayed on its own grid Pressing SETUP A immediately produces a four grid four parameter display SETUP B is also a four parameter display except that channel 1 and channel 2 are overlaid on the upper grid and channel 3 and channel 4 are overlaid on the lower grid The other setup softkeys operate similarly Notice that setups D and F produce displays which include Smith charts Pressing TUTORIAL opens a screen which
494. ue is displayed in Figure 1 74 If the filter is failing the bandwidth test the color of the bandwidth value is red the same color as the failure Wide message of Figure 1 72 If the filter is passing the bandwidth test the displayed bandwidth valueis green the same color as the bandwidth test Pass message 1 95 Making Measurements Using Bandwidth Limits to Test a Bandpass Filter Figure 1 74 Filter Pass Band with Bandwidth Value Displayed Channel 1 Bandwidth Value 1 96 S21 Los BH Wide 18 dB REF 30 dB 52 69 15 Jun 2888 12 48 43 S CENTER 321 000 00G GHz SPAN 200 00A 986 GHZ pa5194e Making Measurements Using Test Sequencing Using Test Sequencing Test sequencing allows you to automate repetitive tasks As you make a measurement the analyzer memorizes the keystrokes Later you can repeat the entire sequence by pressing a single key Becausethe sequence is defined with normal measurement keystrokes you do not need additional programming expertise Subroutines and limited decision making increases the flexibility of test sequences In addition the GPIO outputs can be controlled in a test sequence and the GPIO inputs can be tested in a sequence for conditional branching Thetest sequence function allows you to create title save and execute up to six independent sequences internally You can also save sequences to disk and transfer th
495. ue when the DONE key in the edit limits menu is pressed H owever the easiest way to enter a set of limits is to start with the lowest stimulus value and define the segments from left to right of the display with limit lines turned on as a visual check Phase limit values can be specified between 4500 and 500 Limit values above 4180 and below 180 are mapped into the range of 180 to 180 to correspond with the range of phase data values Offset Limits Menu This menu allows the complete limit set to be offset in either stimulus value or amplitude value This is useful for changing the limits to correspond with a change in the test setup or for device specifications that differ in stimulus or amplitude It can also be used to move thelimit lines away from the data trace temporarily for visual examination of trace detail 7 82 Operating Concepts Knowing the Instrument Modes Knowing the Instrument Modes There are five major instrument modes of the analyzer network analyzer mode external source mode e tuned receiver mode frequency offset operation harmonic mode operation Option 002 Network Analyzer Mode This is the standard mode of operation for the analyzer and is active after you press or switch on the AC power This mode uses the analyzer s internal source Pressing INSTRUMENT MODE NETWORK ANALYZER returns the analyzer tothe normal network analyzer operating mode External Source Mode This
496. units It is used for display of conversion parameters and time domain transform data 7 27 Operating Concepts Analyzer Display Formats Figure 7 11 Linear Magnitude Format CH1 11 lin MAG 100 mU REF OU L 729 69 mU T 137 450 O16 MHz LOG MAG PHASE DELAY SMITH CHART POLAR LIN MAG CENTER 134 000 000 MHz SPAN 30 000 O00 MHz pg6174 c SWR Format The SWR softkey reformats a reflection measurement into its equivalent SWR standing wave ratio value See Figure 7 12 SWR is equivalent to 1 p 1 p where p is the reflection coefficient Note that the results are valid only for reflection measurements If the SWR format is used for measurements of S54 or S45 the results are not valid Figure 7 12 Typical SWR Display CH1 S11 SWR e 7 7 REF 1 i 86 2402 137 150 oie MHZ LOG MAG PHASE DELAY SMITH CHART POLAR LIN MAG SWA MORE CENTER 134 000 DOO MHz SPAN 30 000 000 MHz pg6175 c 7 28 Operating Concepts Analyzer Display Formats Real Format The REAL softkey displays only the real resistive portion of the measured data on a Cartesian format See Figure 7 13 This is similar to the linear magnitude format but can show both positive and negative values It is primarily used for analyzing responses in the time domain and also to display an auxiliary input vol
497. ure 7 1 A detailed block diagram of the analyzer is provided in the service guide together with a theory of system operation Figure 7 1 Simplified Block Diagram of the Network Analyzer System Phase Lock 300 kHz to 3 GHz 300 kHz to 3 GHz or 30 kHz to 6 GHz with Option 006 R 6 GHz with Option 006 Synthesized Source Test Set Receiver Display pa5181e 7 3 Operating Concepts System Operation The Built In Synthesized Source The analyzer s built in synthesized source produces a swept RF signal or CW continuous wave signal in the range of 300 kHz to 3 0 GHz Option 006 is ableto generate signals from 30 kHz to 6 GHz The RF output power is leveled by an internal ALC automatic leveling control circuit To achieve frequency accuracy and phase measuring capability the analyzer is phase locked to a highly stable crystal oscillator For this purpose a portion of the transmitted signal is routed to the R channel input of the receiver where it is sampled by the phase detection loop and fed back to the source Test Sets A test set provides connections to the test device as well as to the signal separation devices The signal separation devices are needed to separate the incident signal from the transmitted and reflected signals The incident signal is applied to the R channel input Meanwhile the transmitted and reflected signals are applied to the A or B inputs Port1 is connected to the A input and port 2 is conne
498. ure varies depending on the frequency spacing and point density therefore the aperture is not constant in log and list frequency sweep modes In list frequency mode extra frequency points can be defined to ensure the desired aperture To obtain a readout of aperture values at different points on thetrace turn on a marker Then press SMOOTHING APERTURE Smoothing aperture becomes the active function and asthe apertureis varied its valuein Hz is displayed beneath the active entry area 7 32 Operating Concepts Electrical Delay Electrical Delay The ELECTRICAL DELAY softkey adjusts the electrical delay to balance the phase of the test device This softkey must be used in conjunction with COAXIAL DELAY or WAVEGUIDE DELAY with cut off frequency in order to identify which type of transmission line the delay is being added to These softkeys can be accessed by pressing the key Electrical delay simulates a variable length lossless transmission line which can be added to or removed from a receiver input to compensate for interconnecting cables etc This function is similar to the mechanical or analog line stretchers of other network analyzers Delay is annotated in units of time with secondary labeling in distance for the current velocity factor With this feature and with MARKER DELAY refer to Setting the Electrical Delay on page 1 37 an equivalent length of air filled lossless transmission line is added or subtracte
499. used 1 Press Preset 2 Select the type of measurement you want to make OV If you want to make a reflection measurement on PORT 1 in the forward direction 513 leave the instrument default setting OY If you want to make a reflection measurement on PORT 2 in the reverse direction S22 press Refl REV S22 B R 3 Set any other measurement parameters that you want for the device measurement power number of points IF bandwidth 4 To access the measurement correction menus press 5 If your calibration kit is different than the kit specified under the CAL KIT softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in the displayed menu refer to Modifying Calibration Kits on page 7 56 6 To select the correction type press CALIBRATE MENU and select the correction type m If you want to make a reflection measurement at PORT 1 press S111 PORT m If you want to make a reflection measurement at PORT 2 press S22 1 PORT 7 Connect a shielded open circuit to PORT 1 or PORT 2 for an Sp measurement 6 26 Calibrating for Increased Measurement Accuracy One Port Reflection Error Correction NOTE Include any adapters that you will have in the device measurement That is connect the calibration standard to the particular connector where you will connect your device under test Figure 6 8 Standard Connections for a One Port Reflection Error Corr
500. values Thetime domain stimulus sidelobe levels depend only on the window selected MINIMUM is essentially no window Consequently it gives the highest sidelobes NORMAL the preset mode gives reduced sidelobes and is the mode most often used MAXIMUM window gives the minimum sidelobes providing the greatest dynamic range USE MEMORY on OFF remembers a user specified window pulse width or step rise time different from the standard window values A window is activated only for viewing a time domain response and does not affect a displayed frequency domain response Figure 3 23 shows thetypical effects of windowing on the time domain response of a short circuit reflection measurement 3 28 Making Time Domain Measurements Windowing Figure 3 23 The Effects of Windowing on the Time Domain Responses of a Short Circuit Real Format WINDOW MINIMUM NORMAL MAXIMUM LOW PASS ub TN E UN STEP LOW PASS IMPULSE B s BANDPASS IMPULSE pb664d 3 29 Making Time Domain Measurements Range Range In thetime domain rangeis defined as the length in time that a measurement can be made without encountering a repetition of the response called aliasing A time domain response repeats at regular intervals because the frequency domain data is taken at discrete frequency points rather than conti nuously over the frequency band 1 Measurement range AF where AF is the spacing between frequency data poin
501. ve Press SAVE FILE tosavethe display information as text in the CSV format Thetext file may beretrieved from the floppy disk on personal computer and can be imported into an application that accepts text in the comma separated value format such as a spreadsheet 4 43 Printing Plotting and Saving Measurement Results Saving Measurement Results How the Analyzer Names These Files Sequentially When text files are saved the analyzer generates the file names automatically in the following format txtcss csv where txt C SS CSV 4 44 is a constant that indicates that this is a text file is the indicator of the channel 1 4 on which the measurement data was taken is a 2 digit sequential indicator of the measurement file index number The file index number may be numbered from 00 31 As the next measurement is taken the file index number is incremented If all four channels are making measurements and a save is performed there will be four channel numbers that share the same file index number For example the files would be named txt 100 csv txt200 csv txt300 csv and txt400 csv If a measurement does not include all four channels unused channel file index numbers will not be used by the next measurement However if all of the files that share a fileindex number are erased that file index number will be re used is the file format comma separated value in this case Printing Plotting and Saving Measurem
502. ve the instrument default setting OY If you want to make a reflection measurement on PORT 2 in the reverse direction S22 press Refl REV S22 B R 3 Set any other measurement parameters that you want for the device measurement power sweep type number of points or IF bandwidth 4 To access the measurement error correction menus press CALIBRATE MENU 5 f your calibration kit is different than the kit specified under the CAL KIT Softkey press CAL KIT SELECT CAL KIT select your type of kit RETURN If your type of calibration kit is not listed in the displayed menu refer to Modifying Calibration Kits on page 7 56 6 To select a response correction press CALIBRATE MENU RESPONSE Connect the short or open calibration standard to the port you selected for the test port PORT 1 for S44 or PORT 2 for S55 NOTE Include any adapters or cables that you will havein the device measurement That is connect the standard device to the particular connector where you will connect your DUT 6 12 Calibrating for Increased Measurement Accuracy Frequency Response Error Corrections Figure 6 2 Standard Connections for a Response Error Correction for Reflection Measurement NETWORK ANALYZER Short Open Short Open For 3 Response For S55 Response pa577e 7 To measure the standard when the displayed trace has settled press SHORT or OPEN If the calibration kit you selected has a choice between male and f
503. vice under test 6 21 Calibrating for Increased Measurement Accuracy Enhanced Frequency Response Error Correction Enhanced Frequency Response Error Correction The enhanced frequency response error correction removes the following errors in both the forward and reverse directions removes directivity errors of the test setup removes source match errors of the test setup removes isolation errors of the test setup optional removes frequency response of the test setup The enhanced reflection error correction may be used to remove load match from the test setup when measuring bilateral devices Enhanced reflection terms are mathematically derived during all enhanced response calibrations but are not applied unless initiated by the ENH REFL on OFF softkey Enhanced reflection correction is applied after the enhanced frequency response error correction is finished IMPORTANT Use enhanced reflection error correction only on bilateral devices A bilateral device has similar forward and reverse transmission characteristics Examples of bilateral devices are passive devices filters attenuators and switches Most active devices amplifiers and some passive devices isolators and circulators are not bilateral If this error correction is used for a non bilateral device errors will occur in the resulting measurement Press Preset_ Select the type of measurement you want to make Q If you want to make measurements in the forwar
504. want the analyzer to make more than one power measurement at each frequency data point press NUMBER OF READINGS x1 where n the number of desired iterations If you increase the number of readings the power meter correction time will substantially increase 9 Press PWRMTR CAL ONE SWEEP TAKE CAL SWEEP NOTE Because power meter calibration requires a longer sweep time you may want toreduce the number of points before pressing TAKE CAL SWEEP After the power meter calibration is finished return the number of points to its original value and the analyzer will automatically interpolate this calibration Some accuracy will belost for the interpolated points The analyzer will use the data table for subsequent sweeps to correct the output power level at each measurement point Also the status annunciator Pc will appear on the analyzer display NOTE You can abort the calibration sweep by pressing PWRMTR CAL OFF 10 Remove the power sensor from the analyzer test port and connect your test device 6 37 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration Using Continuous Correction Mode You can set the analyzer to update the correction table at each sweep as in a leveling application using the continuous sample mode When the analyzer is in this mode it continuously checks power at every point in each sweep You must keep the power meter connected as shown in Figure 6 11 This mode is also kno
505. ward transform range 3 24 four channel display 4 Param Displays softkey 1 18 Channel Position softkey 1 17 customizing 1 17 viewing 1 14 Freelance using 4 21 frequency segments editing 6 34 signals deleting 6 35 span decreasing 5 10 span setting 1 36 frequency bands adding 1 84 changing 1 83 deleting 1 85 setting 1 82 frequency drift 5 5 frequency list sweep of 26 points 2 26 frequency offset mode operation frequency offset mode conversion compression 2 37 Index 4 frequency offset mode conversion loss 2 11 frequency offset operation 7 87 frequency range 1 58 7 88 frequency range setting 1 5 frequency range setting for time domain low pass 3 15 frequency response 7 40 frequency response and isolation error corrections 6 17 reflection measurements 6 19 transmission measurements 6 17 frequency response error corrections 6 12 receiver calibration 6 15 response error correction for reflection measurements 6 12 response error correction for transmission measurements 6 14 frequency response of calibration standards 6 6 electrical offset 6 6 fringe capacitance 6 6 fringe capacitance 6 6 full two port calibration 7 55 full two port error correction 6 29 G gain 1 63 gain compression measuring 1 59 using linear sweep 1 61 gating 3 35 7 8 selecting gate shape 3 36 setting the gate 3 35 general 8 7 generating files in a loop counter example 1 115 German FTZ emissio
506. weep 1 61 linearity phase 2 32 list values printing or plotting 4 32 LO frequency accuracy and stability 2 10 LO to RF isolation 2 42 load match 7 39 7 70 load mismatches mini mizing 2 4 loading a sequence from a disk 1 103 local key 7 77 locking onto a signal with frequency modulation component 7 85 log magnitude format 7 24 logarithmic frequency sweep 7 15 loop counter decision making 1 112 example sequence 1 114 value 2 27 loss of power meter calibration data 6 33 low pass impulse mode 3 20 lower stopband parameters 1 67 M magnitude measuring 1 7 measuring response 1 7 maintenance 8 2 making a basic measurement 1 4 choosing measurement parameters 1 4 connecting required test equipment 1 4 Index 6 connecting the device under test 1 4 error correction 1 5 frequency range setting 1 5 measurement setting 1 5 measuring the device under test 1 5 outputting measurement results 1 6 source power setting 1 5 making harmonic measurements 1 55 making non coaxial measurements 6 50 fixtures 6 50 making reflection response measurements 3 9 making transmission response measurements 3 5 manual sweep time mode 7 11 manual thru 6 62 margin ripple test value 1 87 1 90 markers 1 24 calculating statistics of measurement data 1 42 continuous 1 24 coupling display markers 1 31 CW frequency setting 1 38 delta markers 1 28 discrete 1 24 display markers activating 1 25
507. wer Meter Calibration NETWORK ANALYZER 1000 MHz Low Pass Filter GPIB POWER METER pa536e 3 Select the analyzer as the system controller SYSTEM CONTROLLER 4 Set the power meter s address SET ADDRESSES ADDRESS P MTR GPIB where aa is the power meter GPIB address 5 Select the appropriate power meter by pressing POWER MTR until the correct model number is displayed 436A or 438A 437 NOTE The E4418B and E4419B power meters have a 437 emulation mode This allows these power meters with an 848X series power sensor to be used with the network analyzer In this step when selecting a power meter choose the 438A 437 selection 6 Press PWRMTR CAL LOSS SENSR LISTS CAL FACTOR SENSOR A and enter the correction factors as listed on the power sensor Press ADD FREQUENCY where fff is the frequency in MHz CAL FACTOR where nnn is the calibration factor number DONE for each correction factor When finished press DONE RETURN 2 19 Making Mixer Measurements High Dynamic Range Swept RF IF Conversion Loss 7 Perform a one sweep power meter calibration over the IF frequency range at 5 dBm ONE SWEEP TAKE CAL SWEEP NOTE Because power meter calibration requires a longer sweep time you may want toreducethe number of points before pressing TAKE CAL SWEEP After the power meter calibration is finished return the number of points toits original value and the analyzer will automatically interpolate this calibrati
508. will differ in frequency by AF Because the test signal frequency is slightly different than the receiver frequency the analyzer will err in measuring its magnitude or phase The faster the analyzer s sweep rate the larger AF becomes and the larger the error in the test channel Theanalyzer does not sweep at a constant rate The frequency range is covered in several bands and the sweep rate may be different in each band So if an operator sets up a broadband sweep with the minimum sweep time the error in measuring a long device will be different in each band and the data will be discontinuous at each band edge This can produce confusing results which make it difficult to determine the true response of the device To Improve Measurement Results To reducethe error in these measurements the frequency shift AF must be reduced AF can be reduced by using the following methods decreasing the sweep rate e decreasing the time delay AT 5 7 Optimizing Measurement Results Making Accurate Measurements of Electrically Long Devices Decreasing the Sweep Rate The sweep rate can be decreased by increasing the analyzer s sweep time To increasethe analyzer s sweep time press SWEEP TIME MANUAL and use the front panel knob the and X keys or the front panel keypad enter in the appropriate sweep ti me Alternatively the number of points may be increased for the same frequency range thereby reducing the sweep rate in GHz sec
509. wn as power meter leveling and the speed is limited by the power meter NOTE You may level at theinput of a device under test using a 2 resistor power splitter or a directional coupler before the device or level at the output of the device using a 3 resistor power splitter or a bidirectional coupler after the device Figure 6 11 Continuous Correction Mode for Power Meter Calibration NETWORK ANALYZER Power Splitter Power Sensor pa589e 1 Connect a power splitter or directional coupler to the port supplying RF power to your test device as shown in Figure 6 11 2 Set test port power to approximate desired leveled power 3 Press PWRMTR CAL and enter the test port power level that you want the analyzer to maintain at the input to your test device Compensate for the power loss of the power splitter or directional coupler in the setup 4 If you want the analyzer to make more than one power measurement at each frequency data point press NUMBER OF READINGS wheren the number of desired iterations If you increase the number of readings the power meter correction time will substantially increase 5 Press PWRMTR CAL EACH SWEEP TAKE CAL SWEEP toactivatethe power meter correction 6 38 Calibrating for Increased Measurement Accuracy Power Meter Measurement Calibration To Calibrate the Analyzer Receiver to Measure Absolute Power You can use the power meter calibration as a reference to calibrate the analyzer receive
510. xiliary channel for channel 1 while channel 4 is the auxiliary channel for channel 2 When the channels are uncoupled each channel is processed and controlled independently Data point definition A data point or point is a single piece of data representing a measurement at a single stimulus value Most data processing operations are performed point by point some involve more than one point Sweep definition A sweep is a series of consecutive data point measurements taken over a sequence of stimulus values A few data processing operations requirethat a full sweep of data is available The number of points per sweep can be defined by the user Theunits of the stimulus values such as power frequency and time can change depending on the sweep mode although this does not generally affect the data processing path Processing Details The ADC The ADC analog to digital converter converts the R A and B inputs already down converted to a fixed low frequency IF into digital words The AU X INPUT connector on the rear panel is a fourth input The ADC switches rapidly between these inputs so they are converted nearly simultaneously IF Detection This detection occurs in the digital filter which performs the discrete Fourier transform DF T on the digital words The samples are converted into complex number pairs real plus imaginary R X The complex numbers represent both the magnitude and phase of thelF signal If the AUX
511. y 3 To specify the limit s stimulus value test limits upper and lower and the limit type press STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE NOTE You could also set the upper and lower limits by usingthe MIDDLE VALUE and DELTA LIMITS keys To usethese keys for the entry press MIDDLE VALUE DELTA LIMITS This would correspond to a test specification of 24 3 dB 1 72 Making Measurements Using Limit Lines to Test a Device 4 Todefinethelimit as a flat line press LIMIT TYPE FLAT LINE RETURN 5 Toterminatethe flat line segment by establishing a single point limit press ADD STIMULUS VALUE DONE LIMIT TYPE SINGLE POINT RETURN Figure 1 57 shows the flat limit lines that you have just created with the following parameters e stimulus from 127 MHz to 140 MHz upper limit of 21 dB lower limit of 27 dB Figure 1 57 Example Flat Limit Line CENTER 134 898 920 MHz SPAN 580 008 20G MHz aw000010 Tocreate a limit line that tests the low side of the filter press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE FLATLINE RETURN ADD STIMULUS VALUE DONE LIMIT TYPE SINGLE POINT RETURN 1 73 Making Measurements Using Limit Lines to Test a Device Tocreatea limit linethat tests the high side of the bandpass filter press ADD STIMULUS VALUE UPPER LIMIT LOWER LIMIT DONE LIMIT TYPE FLATLINE RETURN ADD STIMULUS VALUE
512. y still be added e LOAD defines the standard type as a load termination Loads are assigned a terminal impedance equal to the system characteristic impedance ZO but delay and loss offsets may still be added If the load impedance is not ZO use the arbitrary impedance standard definition FIXED defines the load as a fixed not sliding load SLIDING defines the load as a sliding load When such a load is measured during calibration the analyzer will prompt for several load positions and calculate the ideal load value from it OFFSET defines theload as being offset 7 59 Operating Concepts Modifying Calibration Kits DELAY THRU defines the standard type as a transmission line of specified length for calibrating transmission measurements ARBITRARY IMPEDANCE defines the standard type to be a load but with an arbitrary impedance different from system ZO TERMINAL IMPEDANCE allows you to specify the arbitrary impedance of the standard in ohms FIXED defines theload as a fixed not sliding load SLIDING defines theload as a sliding load When such a load is measured during calibration the analyzer will prompt for several load positions and calculate the ideal load value from it Normally arbitrary impedance standards are fixed rather than sliding Any standard type can be further defined with offsets in delay loss and standard impedance assigned minimum or maxi mum frequencies over whi
513. y up to 6 times over a stepped sweep In addition this mode allows the test port power and IF bandwidth to be set independently for each segment that is defined The frequency segments in this mode cannot overlap The ability to completely customize the frequency sweep while using swept list mode is useful when setting up a measurement for a device with high dynamic range like a filter The following measurement of a filter illustrates the advantages of using the swept list mode e For in depth information on swept list mode refer to Swept List Frequency Sweep Hz on page 7 17 Forinformation on optimizing your measurement results when using swept list mode refer to To Use Swept List Mode on page 5 9 Connect the Device Under Test 1 Connect the equipment as shown in Figure 1 52 1 65 Making Measurements Using the Swept List Mode to Test a Device Figure 1 52 Swept List Measurement Setup NETWORK ANALYZER pa53e 2 Set the following measurement parameters Trans FWD S21 B R Observe the Characteristics of the Filter Figure 1 53 Characteristics of a Filter CH1 Spy log MAG 11 dB REF O dB ba PRm M CENTER 900 000 000 MHz SPAN 500 000 O00 MHz pa5110e Generally the passband of a filter exhibits low loss A relatively low incident power may be needed to avoid overdriving the next stage of the DUT if that stage contains an amplifier o
514. z CH4 Markers 1 1 7 885 dB 11i5 88288 MHz 2 3 8129 dB 129 46856 MHz 3 3 3114 dB 133 97608 MHz pg654e 4 Restore the softkey menu and move the marker information back onto the graticules Press lt The display will be similar to Figure 1 15 1 27 Making Measurements Using Markers Figure 1 15 Marker Information on the Graticules 2 Sep 19898 12 09 43 Hi LOG 3 dB REF 2 dB CH2 LOG is dB REF 58 dB Wa 1 4868 dB 154 589 568 MHz S24 4i 53 313 dB 151 583 568 MHz HARKER 1 1i 1 8169 dB Hee 288 MHz EBEN ERE 0 A pde a BE 41565 dB 33 37 688 MHz A CCA PT eT TAT TT i EE E ULELLELLLLII ENTE 134 888 MHz SPAN 45 888 MHZ CENTR 134 888 MHz SFAH 45 888 MHz H3 LOG 16 dB REF 58 dB CH4 LOG 9 dB REF 2 5 dB 42 4i Ti z54 dB 151 583 568 MHz S22 4 2 4148 dE 151 583 588 MHz Pt TTT LL tt PP T E es Markers L dee Las 88208 Me PEER 2 23 108 dB Hl all nFF 3 46 958 MHz amp MODE MEHL etl He i en a EIS m LLELLLELIT CEEEEEELELT EHTE 134 888 MHz SFAH 45 888 MHZ CENTRE 134 668 MHz SPAN 45 668 MHz pg655e You can also restore the softkey menu by pressing a hardkey which opens a menu such as Meas or pressing a softkey To Use Delta Markers This is a relative mode where the marker values show the position of the active marker relative to the delta reference marker You can switch on the delta mode by defining one of the five markers as th
515. zero length or non zero length The same rules for thru and reflect standards used for TRL apply for TRM TRM has noinherent frequency coverage limitations which makes it more convenient in some measurement situations Additionally because TRL requires a different physical length for the thru and the line standards its use becomes impractical for fixtures with contacts that are at a fixed physical distance from each other 7 74 Operating Concepts TRL LRM Calibration For information on how to modify calibration constants for TRL LRM and how to perform a TRL or TRM calibration refer to Calibrating for Non Coaxial Devices on page 6 52 TRL Options The TRL LRM OPTION softkey accesses the TRL LRM options menu There are two selections under this menu e CAL ZO calibration Zo e SET REF set reference The characteristic impedance used during the calibration can be referenced to either the line or match standard CAL ZO LINE ZO or tothe system CAL ZO SYSTEM ZO The analyzer defaults to a calibration impedance that is equal to the line or match standard When the CAL ZO LINE ZO is selected the impedance of the line or match standard is assumed to match the system impedance exactly the line standard is reflectionless After a calibration all measurements are referenced to the impedance of the line standard For example when the line standard is remeasured the response will appear at the center of the Smith

8753ES Option 011 Network Analyzer User`s

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