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User's Guide, N5181A/82A MXG Signal Generators

1. 9 4 FM 10 5 PULSE 10 6 TRIG IN 10 7 TRIG OUT 10 Contents iv Agilent N5181A 82A MXG Signal Generators User s Guide 8 REF IN 10 9 10 MHz OUT 11 10 GPIB 11 11 LAN 11 12 Device USB 11 Digital Modulation Connectors vector models only 12 I OUT QOUT OUT OUT 12 EXT
2. 6 22 Power Switch and LEDs 6 Front Panel Display 7 1 Active Function Area 7 2 Frequency Area 7 3 Annunciators 7 4 Amplitude Area 8 5 Error Message Area 8 6 Text Area 8 7 Softkey Label Area 8 Rear Panel Overview 9 1 AC Power Receptacle 9 2 SWEEP OUT 9 3 AM
3. 98 Trigger Type 99 Trigger Source 100 Example Segment Advance Triggering 101 Example Gated Triggering 102 Example External Triggering 104 Clipping a Waveform 105 How Power Peaks Develop 106 How Peaks Cause Spectral Regrowth 108 How Clipping Reduces Peak to Average Power 109 Configuring Circular Clipping 112 Configuring Rectangular Clipping 113 Contents Agilent N5181A 82A MXG Signal Generators User s Guide vii Scaling a Waveform 114 How DAC
4. 143 No Modulation at the RF Output 143 RF Output Power too Low 143 Distortion 143 Signal Loss While Working with a Spectrum Analyzer 144 Signal Loss While Working with a Mixer 144 Contents viii Agilent N5181A 82A MXG Signal Generators User s Guide Sweep 146 Cannot Turn Off Sweep 146 Sweep Appears Stalled 146 Incorrect List Sweep Dwell Time 146 List Sweep Information is Missing from a Recalled Register 146 Amplitude Does Not Change in List or Step Sweep 146 Internal Media Data Storage 147 Instrument State Saved but the Regist
5. 4 9 Local Cancel Esc 4 10 Help 4 11 Preset and User Preset 4 12 RF Output 5 13 RF On Off and LED 5 14 Mod On Off and LED 5 15 Page Down 5 16 I Input vector models only 5 17 Q Input vector models only 5 18 Knob 6 19 Incr Set 6 20 Return 6 21 More and LED
6. The following example uses the factory preset pulse source and delay 1 Preset the signal generator 2 Set the frequency to 2 GHz 3 Set the amplitude to 0 dBm 4 Set the pulse period to 100 microseconds Press Pulse gt Pulse Period gt 100 gt usec 5 Set the pulse width to 24 microseconds Press Pulse gt Pulse Width gt 24 gt usec 6 Turn on both the pulse modulation and the RF output The PULSE annunciator displays and the RF output LED lights If the modulation does not seem to be working properly refer to No Modulation at the RF Output on page 143 Square Free Run default Triggered Adjustable Doublet Trigger Doublet Gated External Pulse Rate Pulse Period Pulse Period Pulse Delay Pulse Delay Pulse Delay Pulse Delay Pulse Width Pulse Width Pulse Width Pulse Width Pulse Width Pulse 2 Delay Pulse 2 Width Output A 2 GHz 0 dBm carrier modulated by a 24 s pulse that has a period of 100 s 62 Agilent N5181A 82A MXG Signal Generators User s Guide Using Pulse Modulation Option UNU Example Agilent N5181A 82A MXG Signal Generators User s Guide 63 7 Basic Digital Operation No BBG Option Installed Before using this information you should be familiar with the basic operation of the signal generator If you are not comfo
7. 2 View the waveform file name recalled with the instrument state press Mode gt Dual ARB The name is displayed as the selected waveform Recalling the instrument state recalls only the waveform name It does not recreate the waveform file if it was deleted or load the file into BBG media if it is in internal or external media 3 Ensure that the desired waveform file exists and that it is in BBG media page 71 If the waveform file is not in BBG media performing the next step generates an error 4 Turn on the waveform file Press Mode gt Dual ARB gt ARB Off On Example Recalling an Instrument State and Associated List File Recalling an instrument state recalls only the list sweep setup It does not recall the frequency and or amplitude values Because you must load the list file from the file catalog when you store a list file be sure to give it a descriptive name up to 25 characters 1 Recall the desired instrument state see previous example 2 Recall the desired list file a Press Sweep gt More gt Configure List Sweep gt More gt Load Store b Highlight the desired file and press Load From Selected File gt Confirm Load From File 40 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Viewing Saving and Recalling Data Moving or Copying a Stored Instrument State Figure 3 6 Instrument State File Catalog To change a comment on a saved instrument state 1 Press
8. 4 For the selected marker number remove all marker points in the selected segment a Press Set Marker Off Range of Points Notice that the softkeys for the first and last marker points correspond with the length of the waveform The factory supplied waveform SINE_TEST_WFM contains 200 samples To clear all set marker points the range must equal to the length of the waveform b Press Apply To Waveform gt Return 5 Repeat from Step 3 for any remaining marker points that you want to remove from the other markers Clearing a Range of Marker Points The following example uses a waveform with marker points Marker 1 set across points 10 20 This makes it easy to see the affected marker points The same process applies whether the existing points are set over a range or as a single point page 89 1 In the second Arb menu page 87 press Set Markers then select Marker 1 2 Set the first sample point that you want off for this example 13 Press Set Marker Off Range Of Points gt First Mkr Point gt 13 gt Enter 3 Set the last marker point in the range that you want off to a value less than or equal to the number of points in the waveform and greater than or equal to the value set in Step 2 for this example 17 Agilent N5181A 82A MXG Signal Generators User s Guide 89 Basic Digital Operation Option 651 652 654 Using Waveform Markers Press Last Mkr Point gt 17 gt Enter gt Apply To Waveform
9. 20 Internal Baseband Adjustments softkey 125 internal media 41 interpolator filter 116 IP Address softkey 20 address setting 20 auto 20 definition 153 J jitter on EVENT output 97 K keys disabling 139 front panel 3 help on 23 numeric 3 test 149 See also specific key knob 6 17 24 L L annunciator 8 LAN connector 11 definition 153 Services Setup softkey 19 setup 20 Setup softkey 19 Last Mkr Point softkey 87 Last softkey 17 LCD display memory 134 LEDs 6 blink test 149 front panel 6 modulation 34 leveling turning off 47 licenses manager 21 service software 21 signal studio 21 time based 18 troubleshooting 150 viewing 21 waveform 21 line power green LED 6 linear sweep 28 list mode values 30 List softkey 35 list sweep parameters 30 status information 30 troubleshooting 146 using 29 waveform 31 listener mode annunciator 8 LO 153 Load softkeys All From Int Media 70 Cal Array From Step Array 44 From Selected File 37 Load Store 29 37 Segment From Int Media 70 Store 70 Local hardkey 4 lock up troubleshooting 142 logarithmic sweep 28 LXI 153 M main memory 134 manual control sweep 33 Manual softkeys Config Settings 20 Manual 20 Mode 27 Point 27 manuals content of ix Marker softkeys 87 markers signal aligning 83 markers waveform 82 97 media BBG 153 erasing 136 int 153 memory stick 41 storage 41
10. AUXILIARY I O connector see page 13 Events 2 through 4 are available at pins on the AUXILIARY I O connector see page 13 RF Blank Only includes ALC Hold 84 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers waveform ALC Hold Marker Function While you can set a marker function described as Marker Routing on the softkey label either before or after you set marker points page 89 setting a marker function before setting marker points may cause power spikes or loss of power at the RF output Use the ALC hold function by itself when you have a waveform signal that incorporates idle periods burst ramps or when the increased dynamic range encountered with RF blanking page 93 is not desired The ALC hold marker function holds the ALC circuitry at the average value of the sampled points set by the marker s For both positive and negative marker polarity the ALC samples the RF output signal the carrier plus any modulating signal when the marker signal goes high NOTE Because it can affect the waveform s output amplitude do not use the ALC hold for longer than 100 ms For longer time intervals refer to Power Search Mode on page 48 CAUTION Incorrect ALC sampling can create a sudden unleveled condition that may create a spike in the RF output potentially damaging a DUT or connected instrument To prevent this condition ensure that you set
11. Setting a Frequency Multiplier 51 5 Using Analog Modulation Option UNT Only The Basic Procedure 54 Using an External Modulation Source 55 Removing a DC Offset 55 6 Using Pulse Modulation Option UNU Pulse Characteristics 59 The Basic Procedure 61 Example 61 7 Basic Digital Operation No BBG Option Installed I Q Modulation 64 Configuring the Front Panel Inputs 65 Contents vi Agilent N5181A 82A MXG Signal Generators User s Guide 8 Basic Digital Operation Option 651 652 654 Waveform File Basics 68 Sign
12. and USB cables are disconnected from the signal generator and perform the self test again 2 If the self test continues to fail the signal generator requires service If you are unable to service the instrument send the signal generator to an Agilent service center for repair with a detailed description of the failed test s and any other error messages that appeared on the display Refer to Contacting Agilent Technologies on page 151 Displays the details of the currently selected test 150 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting Licenses Licenses A Time Based License Quits Working The instrument s time or date may have been reset forward causing the time based license to expire The instrument s time or date may have been reset backward more than approximately 25 hours causing the instrument to ignore time based licenses See page 18 for details and cautions on setting time and date Cannot Load a Time Based License The instrument s time or date may have been reset backward more than approximately 25 hours causing the instrument to ignore time based licenses See page 18 for details and cautions on setting time and date Agilent N5181A 82A MXG Signal Generators User s Guide 151 Troubleshooting Contacting Agilent Technologies Contacting Agilent Technologies assistance with test and measurements needs and information on finding a local Agilent
13. gt Return This turns off all marker points for the active marker within the range set in Steps 2 and 3 as shown at right How to view markers is described on page 88 Clearing a Single Marker Point Use the steps described in Clearing a Range of Marker Points on page 88 but set both the first and last marker point to the value of the point you want to clear For example if you want to clear a marker on point 5 set both the first and last value to 5 Setting Marker Points in a Waveform Segment To set marker points on a segment the segment must reside in BBG media page 71 When you set marker points they do not replace points that already exist but are set in addition to existing points Because markers are cumulative before you set marker points within a segment view the segment page 88 and remove any unwanted points page 88 Placing a Marker Across a Range of Points 1 In the second Arb menu page 87 press Set Markers 2 Highlight the desired waveform segment 3 Select the desired marker number Press Marker 1 2 3 4 4 Set the first sample point in the range in this example 10 Press Set Marker On Range Of Points gt First Mkr Point gt 10 gt Enter 5 Set the last marker point in the range to a value less than or equal to the number of points in the waveform and greater than or equal to the first marker point in this example 20 Press Last Mkr Point gt 20 gt Enter 6 Pres
14. types 68 134 USB 41 147 memory 134 erasing data from 136 memory See media menu keys 4 messages error 148 mixer troubleshooting signal loss 144 Mod On Off hardkey 5 34 Mode hardkey 69 130 132 modulation AM 53 annunciators 8 carrier signal 34 external source using 55 FM 53 160 Agilent N5181A 82A MXG Signal Generators User s Guide Index generating 34 I Q 64 121 phase 53 pulse 57 troubleshooting 143 Modulator Atten softkey 132 monochrome display setting 16 Monochrome softkey 16 MULT annunciator 8 multiplier using 51 N Name And Store softkey 95 No Retrigger softkey 99 noise 129 noise bandwidth factor 130 Noise softkeys 130 non volatile memory 68 Non Volatile Segments softkey 35 78 number keys 24 numeric keypad 3 O OFFS annunciator 8 offset 64 offsets baseband frequency 72 I Q 125 output using 49 on off switch 6 operation basic 23 operation remote 19 optimization I Q 64 121 options enabling 15 21 resource 2 Options Info softkey 21 Output Blanking softkey 26 output swept 27 over range errors DAC 116 overshoot 116 overview signal generator 1 P Page Up hardkey 4 parameters saving a waveform s 78 path delay 64 PATT TRIG IN connector 13 Patt Trig In softkeys 100 peak to average power reducing 109 performance optimizing 43 persistent memory 135 persistent settings definition 153 resetting 23 restor
15. waveforms including header and marker data normal user operation User data is completely sanitized when you perform the Erase and Sanitize function Persistent Memory Flash 512 MB Yes Yes all user data User data is completely sanitized when you perform the Erase and Sanitize function Calibration Data Memory Flash 128 kB No Yes no user data Table 10 1 Base Instrument Memory Continued Memory Type and Size Writable During Normal Operation Data Retained When Powered Off Purpose Contents Data Input Method Location in Instrument and Remarks 136 Agilent N5181A 82A MXG Signal Generators User s Guide Working in a Secure Environment Removing Data from Memory Option 006 Only Removing Data from Memory Option 006 Only When moving the signal generator from a secure development environment there are several security functions you can use to remove classified proprietary information from the instrument Security functions also have equivalent SCPI commands for remote operation System Subsystem SYSTem commands refer to the SCPI Command Reference CAUTION The signal generator has several memory types described in Table 10 1 on page 134 and Table 10 2 on page 135 and each is used to store a specific type of data Before removing sensitive data understand how each memory type is used Erase All Removes All user files user flatness calibrations user I Q calibrations Rese
16. 2 Set the desired frequency The display equals the output frequency times the multiplier value Examples When using the signal generator as the input to a system you can set the frequency multiplier so that the signal generator displays the output of the system as illustrated below using a doubler Parameter Example 1 Example 2 Example 3 Comments Frequency Multiplier 3 3 4 A multiplier value can be positive or negative Entered and displayed Value 600 MHz 600 MHz 8 GHz Output Frequency 200 MHz 200 MHz 2 GHz The signal generator alerts you if the output frequency is out of range Indicates that a frequency multiplier is on Signal Generator Doubler Output 4 GHz X2 Input 2 GHz Selected Multiplier 2 Signal Generator Output 2 GHz Entered Displayed Frequency 4 GHz 52 Agilent N5181A 82A MXG Signal Generators User s Guide Optimizing Performance Using an Output Offset Reference or Multiplier When measuring mixers the frequency multiplier and frequency offset are often used together In the upconverter example below the multiplier is set to 1 and the offset is set to 3 GHz so that the signal generator displays fRF Mixer Signal Generator local oscillator fLO 800 600 MHz fIF 3000 MHz Selected Multiplier 1 1 Signal Generator Output fLO 800 MHz 600 MHz fRF 2200 2400 MHz Selected Offset 3000 MHz 3000 MHz Entered Displ
17. Agilent N5181A 82A MXG Signal Generators User s Guide 65 Basic Digital Operation No BBG Option Installed I Q Modulation Configuring the Front Panel Inputs The Agilent MXG accepts externally supplied analog I and Q signals through the front panel I Input and Q Input for modulating onto the carrier 1 Connect I and Q signals to the front panel connectors a Connect an analog I signal to the signal generator s front panel I Input b Connect an analog Q signal to the signal generator s front panel Q Input 2 Turn on the I Q modulator Press I Q Off On to On 3 Configure the RF output a Set the carrier frequency b Set the carrier amplitude c Turn the RF output on 4 Make adjustments to the I Q signals page 64 as needed 66 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation No BBG Option Installed I Q Modulation Agilent N5181A 82A MXG Signal Generators User s Guide 67 8 Basic Digital Operation Option 651 652 654 Before using this information you should be familiar with the basic operation of the signal generator If you are not comfortable with functions such as setting power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter The features described in this chapter are available only in vector signal generators with Option 651 652 or 654 Waveform File Bas
18. CLOCK 12 EVENT 1 12 PAT TRIG IN 13 DIGITAL BUS I O 13 AUX I O 13 2 Setting Preferences amp Enabling Options User Preferences 16 Display Settings 16 Power On and Preset 17 Front Panel Knob Resolution 17 Setting Time and Date 18 Upgrading Firmware 18 Remote Operation Preferences 19 Configuring the GPIB
19. Change the repetition for the selected entry to 200 Press Edit Repetitions gt 200 gt Enter 4 Save the changes made in the previous steps Press More gt Name and Store gt Enter To save the changes as a new sequence Agilent N5181A 82A MXG Signal Generators User s Guide 77 Basic Digital Operation Option 651 652 654 Waveform Sequences a Press More gt Name and Store gt Clear Text b Enter a file name for example SINE100 RMP200 c Press Enter The edited sequence saves as a new waveform sequence Playing a Sequence If you have not created a waveform sequence refer to Creating a Sequence on page 75 NOTE To play a waveform segment individually or as part of a waveform sequence the segment must reside in BBG media See also Loading a Waveform Segment into BBG Media Volatile Memory on page 71 1 Select a waveform sequence a Press Mode gt Dual ARB gt Select Waveform b Highlight a waveform sequence for this example SINE100 RMP200 from the Sequence On column c Press Select Waveform The display shows the currently selected waveform for example Selected Waveform SEQ SINE100 RMP200 2 Generate the waveform Press ARB Off On to On This plays the selected waveform sequence During the waveform sequence generation both the I Q and ARB annunciators turn on and the waveform modulates the RF carrier 3 Configure the RF output a Set the RF carrier fre
20. DHCP MAC Web Server HTTP List Mode Sequence Default Gateway VXI 11 SCPI User Power Correction Sockets SCPI TELNET Display State On Off ARB Files List Files I Q Calibration Data Frequency 800 MHz Amplitude 0 dBm RF on Instrument settings states save to instrument state memory which is divided into 10 sequences 0 through 9 each sequence comprises 100 registers 00 through 99 Delete softkeys in the Save and Recall menus enable you to delete the contents of a specific register or the contents of all sequences in the state file catalog The signal generator requires that you confirm a deletion For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 39 Basic Operation Viewing Saving and Recalling Data Example Recalling an Instrument State 1 Preset the signal generator 2 Press Recall The Select Seq softkey shows the last sequence used and the display lists any states stored in the registers in that sequence RECALL Reg is the active entry 3 Select the desired instrument state If the desired state is listed in the currently selected sequence press desired number gt Enter If not press Press Select Seq gt desired number gt Enter gt RECALL Reg gt desired number gt Enter Example Recalling an Instrument State and Associated Waveform File 1 Recall the desired instrument state see previous example
21. Markers in a Waveform Sequence on page 95 This section also provides the following information Waveform Marker Concepts on page 83 Accessing Marker Utilities on page 87 Viewing Waveform Segment Markers on page 88 Viewing a Marker Pulse on page 92 Using the RF Blanking Marker Function on page 93 Setting Marker Polarity on page 94 Agilent N5181A 82A MXG Signal Generators User s Guide 83 Basic Digital Operation Option 651 652 654 Using Waveform Markers Waveform Marker Concepts The signal generator s Dual ARB provides four waveform markers to mark specific points on a waveform segment You can set each marker s polarity and marker points on a single sample point or over a range of sample points Each marker can also perform ALC hold or RF Blanking and ALC hold Marker Signal Response The signal generator aligns the marker signals with the I and Q signals at the baseband generator However some settings such as amplitude filters and so forth within the RF output path can create delays between the marker EVENT output signal and the modulated RF output When using the marker EVENT output signal observe the signals marker relative to modulated RF for any latency and if needed reset the marker point positions include delay page 125 or both Marker File Generation Downloading a waveform file as described in the Programming Guide that does
22. Over Range Errors Occur 116 How Scaling Eliminates DAC Over Range Errors 117 Setting Waveform Runtime Scaling 118 Setting Waveform Scaling 119 I Q Modulation 121 Using the Rear Panel I and Q Outputs 122 Configuring the Front Panel Inputs 124 I Q Adjustments 125 I Q Calibration 127 9 Adding Real Time Noise to a Signal Option 403 Adding Real Time Noise to a Dual ARB Waveform 130 Using Real Time I Q Baseband AWGN 132 10 Working in a Secure Environment Understanding Memory Types 134 Removing Data from Mem
23. Power on page 109 CAUTION Clipping is non reversible and cumulative Save a copy of the waveform file before you apply clipping Copy a Waveform File 1 Display the signal generator s files Press File gt Catalog Type gt More gt Volatile Segments 2 Highlight the waveform RAMP_TEST_WFM 3 Press Copy File 4 Name the copy in this example the name is MY_TEST_REC and press Enter Apply Rectangular Clipping to the Copied Waveform File 1 Open the DUAL ARB Waveform Utilities menu Press Mode gt Dual ARB gt More gt More gt Waveform Utilities 2 In the list of files highlight the copied file in this example MY_TEST_REC 3 Create the CCDF plot Press Plot CCDF 4 Observe the shape and position of the waveform s curve the dark line in the example at right 5 Activate rectangular clipping Press Return gt Clipping gt Clipping Type until I Q highlights 6 Set 80 clipping for the I data Press Clip I To gt 80 gt 7 Set 40 clipping for the Q data Press Clip Q To gt 40 gt 8 Apply the rectangular clipping to the waveform Press Apply to Waveform 9 Create the CCDF plot see the example at right Press Plot CCDF 10 Observe the waveform s curve after clipping Note the reduction in peak to average power relative to the previous plot Example waveform curve before clipping Example waveform curve after circular clipping 114 Agilent
24. Save 2 Highlight the desired register 3 Press Edit Comment In Seq n Reg nn 4 Press Re SAVE Seq n Reg nn This overwrites previously saved instrument state settings with the new comment Sequence Register A user created state file s default name is its memory location To move the file rename it to the desired sequence and register You can not give a file the same name as an existing file Caution If you rename a state file to something other than a valid sequence register name the file does not appear in either the Save or Recall menu User Preset Information If you rename this file the signal generator no longer recognizes it as user preset information Defining a User Preset Set up the instrument as desired then press User gt Save User Preset Creating More than One User Preset Set up several preset conditions under different names give the one you wish to use the name USRPRST To use a different file rename the current USRPRST then give the desired file the name USRPRST Note To define a user preset set up the instrument as desired and press User gt Save User Preset Agilent N5181A 82A MXG Signal Generators User s Guide 41 Basic Operation Viewing Saving and Recalling Data Selecting Internal or External Media In the External Media menu shown below select the desired storage type Using External Media When you connect storage media to the front panel USB connector t
25. an auxiliary signal is routed to a rear panel event output that corresponds to the marker number Event 1 is available at both the EVENT 1 BNC connector see page 12 and a pin on the AUXILIARY I O connector see page 13 Events 2 through 4 are available at pins on the AUXILIARY I O connector see page 13 You can use an auxiliary output signal to synchronize another instrument with the waveform or as a trigger signal to start a measurement at a given point on a waveform You can also configure markers to initiate ALC hold or RF Blanking which includes ALC hold Refer to Using Waveform Markers on page 82 for details When you download a waveform file that does not have a marker file associated with it the signal generator creates a marker file without any marker points Factory supplied segments have a marker point on the first sample for all four markers The following procedures demonstrate how to use markers while working in the dual ARB player These procedures also discuss two types of points a marker point and a sample point A marker point is a point at which a given marker is set on a waveform you can set one or more marker points for each marker A sample point is one of the many points that compose a waveform There are three basic steps to using waveform markers Clearing Marker Points from a Waveform Segment on page 88 Setting Marker Points in a Waveform Segment on page 89 Controlling
26. and Segment Advance modes use the Ext Polarity softkey to set the external trigger polarity In Gated mode the Active Low and Active High softkeys page 99 determine the external trigger polarity Mode gt Dual ARB gt Trigger Source gt Patt Trig In BNC connector see page 13 Aux I O connector see page 13 Neg the signal generator responds during the trigger signal low state Pos the signal generator responds during the trigger signal high state For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 101 Basic Digital Operation Option 651 652 654 Triggering a Waveform Example Segment Advance Triggering Segment advance triggering enables you to control the segment playback within a waveform sequence This type of triggering ignores the repetition value page 76 For example if a segment has repetition value of 50 and you select Single as the segment advance triggering mode the segment still plays only once The following example uses a waveform sequence that has two segments If you have not created and stored a waveform sequence refer to Creating a Sequence on page 75 1 Preset the signal generator 2 Configure the RF output Set the desired frequency Set the desired amplitude Turn on the RF output 3 Select a waveform sequence for playback a Press Mode gt Dual ARB gt Select Wavefor
27. as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 21 Setting Preferences amp Enabling Options Enabling an Option Enabling an Option There are two ways to enable an option Use the License Manager software utility 1 Download the utility from www agilent com find LicenseManager 2 Run the utility and follow the prompts Use SCPI commands as described in the Programming Guide Viewing Options and Licenses Utility gt Instrument Info gt Service Software Licenses Waveform licenses from some Instrument options appear here A check mark means that an option is enabled For details on each key use key help as described on page 23 Signal Studio applications appear here appear here 22 Agilent N5181A 82A MXG Signal Generators User s Guide Setting Preferences amp Enabling Options Enabling an Option Agilent N5181A 82A MXG Signal Generators User s Guide 23 3 Basic Operation This chapter introduces fundamental front panel operation For information on remote operation refer to the Programming Guide Presetting the Signal Generator below Viewing Key Descriptions below Entering and Editing Numbers and Text on page 24 Setting Frequency and Power Amplitude on page 26 Configuring a Swept Output on page 27 Modulating the Carrier Signal on page 34 Viewing Saving and Recalling Data on page 35 Rea
28. can set the following user preferences Display Settings below Power On and Preset on page 17 Front Panel Knob Resolution on page 17 Display Settings NOTE With both brightness and contrast set to minimum the display may be too dark to see the softkeys If this happens use the figure above to locate the brightness and contrast softkeys and adjust their values so that you can see the display Range 15 100 Range 35 55 Range 1 12 hours in 1 hour increments Light Only turns the display light off leaving the text visible at a low intensity Light amp Text turns the display light and the text off If the display remains unchanged for long periods of time use this mode to prevent the text from burning the display When on commands executed through the remote control bus update the signal generator display accordingly Bright without color Utility gt Display gt See also Using the Secure Display Option 006 Only on page For details on each key use key help as described on page 23 page 137 Dark text on a light background Light text on a dark background Agilent N5181A 82A MXG Signal Generators User s Guide 17 Setting Preferences amp Enabling Options User Preferences Power On and Preset Front Panel Knob Resolution Select the GPIB language desired after a preset See also the Programming Guide and the SCPI Reference Utility gt Power On Preset gt Re
29. converts digital I and Q baseband waveforms to analog waveforms Because the clock rate of the interpolator is four times that of the baseband clock the interpolator calculates sample points between the incoming baseband samples and smooths the waveform as shown in the figure at the right The interpolation filters in the DACs overshoot the baseband waveform If a baseband waveform has a fast rising edge the interpolator filter s overshoot becomes a component of the interpolated baseband waveform This response causes a ripple or ringing effect at the peak of the rising edge If this ripple overshoots the upper limit of the DAC range the interpolator calculates erroneous sample points and is unable to replicate the true form of the ripple see the figure at the right As a result the signal generator reports a DAC over range error Agilent N5181A 82A MXG Signal Generators User s Guide 117 Basic Digital Operation Option 651 652 654 Scaling a Waveform How Scaling Eliminates DAC Over Range Errors Scaling reduces the amplitude of the baseband waveform while maintaining its basic shape and characteristics such as peak to average power ratio If the fast rising baseband waveform is scaled enough to allow an adequate margin for the interpolator filter overshoot the interpolator filter can calculate sample points that include the ripple effect and eliminate the over range error see the figure at the right Althou
30. displays 0 00 Hz indicating that this is the RF output frequency zero level All frequencies entered are interpreted as being relative to this reference frequency Amplitude Press Amptd gt More gt Amptd Ref Set The amplitude displays 0 00 dB indicating that this is the RF output amplitude zero level All amplitudes entered are interpreted as being relative to this reference amplitude Examples To set a new frequency or amplitude reference turn the frequency reference off and then follow the steps above Parameter Example 1 Example 2 Example 3 Comments Reference 50 MHz 50 MHz 2 GHz A reference value must be positive Entered and displayed Value 2 MHz 2 MHz 1 GHz The entered value can be positive or negative Output Frequency 52 MHz 48 MHz 1 GHz The signal generator alerts you if the output frequency or amplitude is out of range Indicates that a reference is on Agilent N5181A 82A MXG Signal Generators User s Guide 51 Optimizing Performance Using an Output Offset Reference or Multiplier Setting a Frequency Multiplier Using a frequency multiplier the signal generator can display a frequency that is the multiple positive or negative of the output value Displayed Value multiplier value output frequency Output Frequency displayed value multiplier value To set a frequency multiplier 1 Press Frequency gt Freq Multiplier gt multiplier value gt x
31. existing value down Highlight the dwell time in row 7 and press Insert Item 11 For an analog instrument go to step 14 For a vector instrument continue with step 12 12 Select a waveform for point 2 a Highlight the waveform entry for point 2 and press the More gt Select Waveform The signal generator displays the available waveforms as shown in the following example b Highlight the desired waveform in this example SINE_TEST and press either the Select hardkey or the Select Waveform softkey Either select a waveform or select no modulation 32 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Configuring a Swept Output 13 As desired repeat step 12 for the remaining points for which you want to select a waveform The following figure shows an example of how this might look 14 Turn sweep on Press Return gt Return gt Return gt Sweep gt Freq Off On gt Amptd Off On gt Waveform Off On 15 If it is not already on turn the RF output on Press RF On Off The SWEEP annunciator appears on the display indicating that the signal generator is sweeping and the progress bar shows the progression of the sweep Example Using a Single Sweep 1 Set up either a step sweep page 28 or a list sweep page 30 2 In the List Sweep menu set the sweep repeat to single Press Sweep Repeat Single Cont to highlight Single Sweep does not occur until you trigger it Note that t
32. frequency does not display for an amplitude sweep the amplitude does not display for a frequency and amplitude sweep neither frequency nor amplitude displays Progress Bar very fast sweeps can appear to sweep randomly or backward See page 33 For details on each key use key help as described on page 23 28 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Configuring a Swept Output Step Sweep Step sweep provides a linear or logarithmic progression from one selected frequency or amplitude or both to another pausing at linearly or logarithmically spaced points steps along the sweep The sweep can progress forward backward or manually Example Configuring a Continuous Linear Step Sweep 1 Preset the instrument and open the Sweep List menu Press Preset gt SWEEP Because continuous is the default sweep repeat selection and linear is the default step spacing selection you do not need to set these parameters 2 Open the step sweep menu Press Configure Step Sweep 3 Set the following parameters 4 Sweep both frequency and amplitude Press Return gt Return gt Sweep gt Freq Off On gt Amptd Off On A continuous sweep begins from the start frequency amplitude to the stop frequency amplitude The SWEEP annunciator displays both the CW frequency and the amplitude display blank indicating that both are sweeping and the progress bar shows the sweep progress 5 Turn the RF
33. instrument may be in remote mode which locks the keypad To exit remote mode and unlock the preset keys press Local Cancel Esc Pressing Preset Performs a User Preset This behavior results from the use of a backward compatible SCPI command To return the signal generator to normal use send the command SYST PRESet TYPE NORM For information on SG 1364 U SCPI commands refer to the SCPI Command Reference 148 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting Error Messages Error Messages Error Message Types Events do not generate more than one type of error For example an event that generates a query error does not generate a device specific execution or command error Query Errors 499 to 400 indicate that the instrument s output queue control has detected a problem with the message exchange protocol described in IEEE 488 2 Chapter 6 Errors in this class set the query error bit bit 2 in the event status register IEEE 488 2 section 11 5 1 These errors correspond to message exchange protocol errors described in IEEE 488 2 6 5 In this case Either an attempt is being made to read data from the output queue when no output is either present or pending or data in the output queue has been lost Device Specific Errors 399 to 300 201 to 703 and 800 to 810 indicate that a device operation did not properly complete possibly due to an abnormal hardware or firmwar
34. is Empty or Contains the Wrong State External Media Data Storage on page 147 Instrument Recognizes External Media Connection but Does Not Display Files Preset on page 147 The Signal Generator Does Not Respond Pressing Preset Performs a User Preset Error Messages on page 148 Front Panel Tests on page 149 Self Test on page 149 Licenses on page 150 Contacting Agilent Technologies on page 151 Returning a Signal Generator to Agilent 142 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting Display Display The Display is Too Dark to Read Both brightness and contrast may be set to minimum Use the figure in Display Settings on page 16 to locate the brightness and contrast softkeys and adjust their values so that you can see the display Signal Generator Lock Up Ensure that the signal generator is not in remote mode the R annunciator shows on the display To exit remote mode and unlock the front panel press Local Cancel Esc Ensure that the signal generator is not in local lockout which prevents front panel operation For information on local lockout refer to the Programming Guide If a progress bar appears on the signal generator display an operation is in progress Preset the signal generator Cycle power on the signal generator Agilent N5181A 82A MXG Signal Generators User s Guide 143 Troubl
35. is beyond the specific limits Explanation is provided in the Error Message file see page 148 This is not displayed on the instrument Message number and longer description new indicates a message generated since messages were last viewed The annunciator indicates an unviewed message Error messages appear in the lower left corner of the display as they occur Agilent N5181A 82A MXG Signal Generators User s Guide 43 4 Optimizing Performance Before using this information you should be familiar with the basic operation of the signal generator If you are not comfortable with functions such as setting the power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter Using User Flatness Correction on page 44 Using Unleveled Operating Modes on page 47 Using an Output Offset Reference or Multiplier on page 49 44 Agilent N5181A 82A MXG Signal Generators User s Guide Optimizing Performance Using User Flatness Correction Using User Flatness Correction User flatness correction enables you to adjust the RF output amplitude for up to 1601 sequential linearly or arbitrarily spaced frequency points to compensate for external losses in cables switches or other devices You can create and save individual user flatness correction tables which enables you to recall different correction arrays for various test setups or freque
36. key help as described on page 23 125 MHz 6 20 833 MHz The jitter is gone with an optimal sample rate Waveform appears to exhibit jitter when triggered using EVENT signal with jitter Oscilloscope triggering on waveform Oscilloscope triggering on EVENT signal Oscilloscope triggering on EVENT signal EVENT output signal exhibits jitter due to a non optimal sample rate 98 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Triggering a Waveform Triggering a Waveform Figure 8 8 Triggering Softkeys Triggers control data transmission by controlling when the signal generator transmits the modulating signal You can configure trigger settings so that data transmission occurs once Single mode continuously Continuous mode or starts and stops repeatedly Gated and Segment Advance modes A trigger signal contains both positive and negative states you can use either for triggering When you initially select a trigger mode or when you change from one triggering mode to another you may lose the carrier signal at the RF output until the modulating signal is triggered This is because the signal generator sets the I and Q signals to zero volts prior to the first trigger event To maintain the carrier signal at the RF output create a data pattern with the initial I and Q voltages set to values other than zero There are two parts to configuring a waveform trigger Ty
37. least one marker point set page 89 The process is the same for a waveform sequence This example uses the factory supplied segment SINE_TEST_WFM in the dual ARB Player Factory supplied segments have a marker point on the first sample point for all four markers as shown 1 In the first Arb menu page 69 press Select Waveform 2 Highlight the SINE_TEST_WFM segment and press Select Waveform 3 Press ARB Off On to On 4 Connect the Agilent MXG s rear panel Q OUT output to the oscilloscope s channel 1 input 5 Connect the signal generator s rear panel EVENT 1 output to the oscilloscope s channel 2 input When marker 1 is present the Agilent MXG outputs a signal through EVENT 1 as shown in the following example Marker points on first sample point of waveform segment How to view markers is described on page 88 RF Output Marker pulse on the Event 1 signal Agilent N5181A 82A MXG Signal Generators User s Guide 93 Basic Digital Operation Option 651 652 654 Using Waveform Markers Using the RF Blanking Marker Function While you can set a marker function described as Marker Routing on the softkey label in the second Arb menu either before or after setting the marker points page 89 setting a marker function before you set marker points may change the RF output RF Blanking includes ALC hold described on page 84 note Caution regarding unleveled power The signal generator blanks the RF outpu
38. markers to let the ALC sample over an amplitude that accounts for the higher power levels encountered within the signal Positive The signal is sampled during the on marker points Negative The signal is sampled during the off marker points Positive Polarity Agilent N5181A 82A MXG Signal Generators User s Guide 85 Basic Digital Operation Option 651 652 654 Using Waveform Markers Close up of averaging The ALC samples the waveform when the marker signal goes high and uses the average of the sampled waveform to set the ALC circuitry Here the ALC samples during the on marker points positive polarity Marker Marker Marker Marker Example of Correct Use Waveform 1022 points Marker range 95 97 Marker polarity Positive This example shows a marker set to sample the waveform s area of highest amplitude Note that the marker is set well before the waveform s area of lowest amplitude This takes into account any response difference between the marker and the waveform signal Pulse Unleveled Example of Incorrect Use Waveform 1022 points Marker range 110 1022 Marker polarity Positive This example shows a marker set to sample the low part of the same waveform which sets the ALC modulator circuitry for that level this usually results in an unleveled condition for the signal generator when it encounters the high amplitude of the pulse Marker Marker 86 Agilent N5181A 82A MXG Signal Generators U
39. medium sized systems See also http www lxistandard org P Persistent Settings States Settings unaffected by preset user preset or power cycle Point to point Time In a step sweep see page 28 the sum of the dwell time plus processing time switching time and settling time 154 Agilent N5181A 82A MXG Signal Generators User s Guide R RMS Root mean square A time varying signal s effective value the equivalent DC voltage required to generate the equivalent heat across a given resistor For a sinewave RMS 0 707 x peak value S Softkey A button located along the instrument s display that performs whatever function is shown next to it on that display T TCP Transmission control protocol The most common transport layer protocol used on Ethernet and the Internet Terminator A unit indicator such as Hz or dBm that completes an entry For example for the entry 100 Hz Hz is the terminator Type N Connector Threaded RF connector used to join coaxial cables U USB Universal serial bus See also http www usb org Agilent N5181A 82A MXG Signal Generators User s Guide 155 Index Symbols points softkey 28 Skipped Points softkey 87 M annunciator 7 dc offset removing 55 hardkey 53 softkeys 53 55 Numerics 10 MHz OUT connector 11 100Base T LAN cable 20 628 error 72 8648A B C D softkey 19 8656B 8657A B softkey 19 A AC power receptacle 9 Activate Secure
40. must reside in BBG media before they can be played edited or included in a sequence Cycling power or rebooting the signal generator deletes the files in BBG media NOTE Each time the instrument powers up two factory supplied segments are automatically created in BBG media RAMP_TEST_WFM and SINE_TEST_WFM 1 Press Mode gt Dual ARB gt Select Waveform gt Waveform Segments 2 Press Load Store to highlight Load 3 Highlight the waveform segment you want to load 4 If there is already a copy of this segment in the currently selected media and you do not want to overwrite it rename the waveform segment before you load it refer to the previous procedure 5 Press Load Segment From currently selected Media To load all files from the currently selected media into BBG media press Load All From currently selected Media Playing a Waveform Segment 1 Press Mode gt Dual ARB gt Select Waveform 2 In the Segment on BBG Media column highlight the waveform segment you want to play 3 Press Select Waveform gt ARB Off On to On This plays the selected waveform segment During the waveform segment generation both the I Q and ARB annunciators turn on and the waveform modulates the RF carrier 4 Configure the RF Output a Set the RF carrier frequency b Set the RF output amplitude c Turn on the RF output The waveform segment is now available at the signal generator s RF OUTPUT connector Curr
41. occurs on the low part of the signal regardless of the polarity setting Agilent N5181A 82A MXG Signal Generators User s Guide 95 Basic Digital Operation Option 651 652 654 Using Waveform Markers Controlling Markers in a Waveform Sequence In a waveform segment an enabled marker point generates an auxiliary output signal that is routed to the rear panel EVENT output described in Rear Panel Overview on page 9 corresponding to that marker number For a waveform sequence you enable or disable markers on a segment by segment basis this enables you to output markers for some segments in a sequence but not for others Unless you change the sequence marker settings or cycle the power the marker setting for the last segment edited in the sequence applies to all segments in the next sequence that you build For information on building a waveform sequence see Creating a Sequence on page 75 Figure 8 7 Waveform Sequence Menus for Enabling Disabling Segment Markers Mode gt Dual ARB gt More gt More gt Note This is the third Arb menu For details on each key use key help as described on page 23 Enable Disable markers while creating a waveform sequence Edit a sequence to enable disable markers 96 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Enabling and Disabling Markers in a Waveform Sequence Select the waveform segment
42. office http www agilent com find assist accessories or documentation http www agilent com find mxg new firmware releases http www agilent com find upgradeassistant If you do not have access to the Internet please contact your field engineer NOTE In any correspondence or telephone conversation refer to the signal generator by its model number and full serial number With this information the Agilent representative can determine whether your unit is still within its warranty period Returning a Signal Generator to Agilent Use the following steps to return a signal generator to Agilent Technologies for servicing 1 Gather as much information as possible regarding the signal generator s problem 2 Call the phone number listed on the Internet http www agilent com find assist that is specific to your geographic location If you do not have access to the Internet contact your Agilent field engineer After sharing information regarding the signal generator and its condition you will receive information regarding where to ship your signal generator for repair 3 Ship the signal generator in the original factory packaging materials if available or use similar packaging to properly protect the signal generator 152 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting Contacting Agilent Technologies Agilent N5181A 82A MXG Signal Generators User s Guide 153 Glossary A A
43. rate setting is shown in the figure at right The EVENT output signal can exhibit jitter of up to 4 ns on the rising and falling edge This jitter can be minimized in either of two ways Method 1 Use a sample clock of 125 MHz N where N is a positive integer and where 125 MHz N can be represented exactly on the display For example 125 MHz 62 5 MHz 31 25 MHz 25 MHz and so on If the result cannot be represented exactly on the display jitter will be present For example N 6 will result in jitter because which is truncated when displayed Method 2 Select a sample clock and waveform length that spaces the markers by a multiple of 8 ns For example A 200 point waveform with a marker on the first point and a sample clock of 50 MHz provides a marker every 4 s Because 4 s is a multiple of 8 ns the jitter is minimized When the EVENT output signal exhibits jitter and it is used as a measurement trigger it can cause the waveform to falsely appear as having jitter If this condition occurs you can adjust the sample rate to a value see above that does not cause the jitter appearance To maintain the integrity of the original waveform with a sample rate change you will have to also recalculate the sample values The following figures illustrate the marker signal jitter and its affect on the waveform Sample rate setting The settings in this menu can be stored to the file header see page 78 For details on each key use
44. same purpose as a chip erase System files are restored after erase 138 Agilent N5181A 82A MXG Signal Generators User s Guide Working in a Secure Environment Removing Data from Memory Option 006 Only Securing a Nonfunctioning Instrument If the instrument is not functioning and you are unable to use the security functions you must physically remove the processor board and for vector instruments the A4 Memory Chip from the instrument Once these assemblies are removed choose one of the following options Discard the board or boards and send the instrument to a repair facility A new board or boards will be installed and the instrument will be repaired and calibrated If the instrument is still under warranty you will not be charged for new boards If you have another working instrument install the board or boards into that instrument and erase the memory Then reinstall the board or boards back into the nonworking instrument and send it to a repair facility for repair and calibration If you discover that one or both of the boards do not function in the working instrument discard the nonfunctioning board and note on the repair order that it caused the instrument failure If the instrument is still under warranty you will not be charged for new boards For instructions on how to remove and replace boards refer to the Service Guide Agilent N5181A 82A MXG Signal Generators User s Guide 139 Working in a Sec
45. the progress bar see Configuring a Swept Output on page 27 If the sweep appears to stall check the following 1 Turn on the sweep with one of the following key sequences Sweep gt Sweep gt Freq Sweep gt Sweep gt Amptd Sweep gt Sweep gt Waveform vector instruments only 2 If the sweep is in single mode press the Single Sweep softkey 3 If the sweep trigger indicated by the Sweep Trigger softkey is not set to Free Run set it to Free Run to determine if a missing sweep trigger is blocking the sweep 4 If the point trigger indicated by the Point Trigger softkey is not set to Free Run set it to Free Run to determine if a missing point trigger is blocking the sweep 5 Set the dwell time to one second to determine if the dwell time was set to a value that was too slow or too fast to see 6 Ensure that you set at least two points in the step sweep or list sweep Incorrect List Sweep Dwell Time 1 Press Sweep gt More gt Configure List Sweep 2 Check that the list sweep dwell values are accurate 3 If the dwell values are incorrect edit them If the dwell values are correct continue to the next step 4 Press More and ensure that the Dwell Type List Step softkey is set to List If Step is selected the signal generator sweeps the list points using the dwell time set for step sweep rather than list sweep See also Configuring a Swept Output on page 27 List Sweep Informati
46. type to list Press SWEEP gt Sweep Type List Step to highlight List The display shows sweep list parameters as shown below 3 Open the List Sweep menu Press More gt Configure List Sweep 4 Clear any previously set values from the menu and load the points defined in the step sweep into the list Press More gt Preset List gt Preset with Step Sweep gt Confirm Preset The display updates with the values loaded from the step sweep as shown 5 Sweep frequency and amplitude Press SWEEP hardkey gt Sweep gt Freq Off On gt Amptd Off On Setting the sweep turns on the sweep function a continuous sweep begins On the display the SWEEP annunciator appears and the progress bar shows the progression of the sweep 6 If not already on turn the RF output on Press RF On Off The RF Output LED lights and a continuous sweep is available at the RF OUTPUT connector Vector Models Presetting the list clears any previously selected waveforms For information on selecting a list sweep waveform see Example Editing List Sweep Points on page 31 Waveforms are available only on vector models Agilent N5181A 82A MXG Signal Generators User s Guide 31 Basic Operation Configuring a Swept Output Example Editing List Sweep Points If you are not familiar with table editors refer to page 25 1 Create the desired list sweep This example uses the list sweep created in the previous example 2 If sweep is o
47. waveform files in addition to building waveform sequences The dual ARB waveform player also provides markers page 82 triggering page 98 clipping page 105 and scaling page 114 capabilities Most procedures in this section start from the Dual ARB menu shown below Agilent N5181A 82A MXG Signal Generators User s Guide 69 Basic Digital Operation Option 651 652 654 Waveform File Basics Figure 8 1 Dual ARB Softkeys page 130 page 10 page 114 page 10 page 70 If you set the ARB sample clock when the dual ARB is off the new setting is applied when the dual ARB player is turned on this setting survives toggling the Dual ARB player off and on page 82 page 78 page 98 For details on each key use key help as described on page 23 Note This is the first of three Arb menus Note This is second of three Arb menus Note This is third of three Arb menus page 74 page 72 page 114 70 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Storing Loading and Playing a Waveform Segment Storing Loading and Playing a Waveform Segment See also Viewing Saving and Recalling Data on page 35 Figure 8 2 Waveform Segment Softkeys Storing Renaming a Waveform Segment to Non Volatile Memory Internal or External Media Use the following steps to store a copy of a file in BBG memory to the currently selected media page 41 If you have n
48. 20 Diff Mode softkeys 125 DIGBUS annunciator 8 digital bus 13 digital operation 67 digital signal to analog waveform 116 display blanking 139 error message area 8 overview 3 7 secure 139 settings 16 softkey labels 8 tests 149 text area 8 troubleshooting 142 display memory 134 Display softkey 15 Display Waveform And Markers softkey 87 Displayed Case softkey 24 distortion troubleshooting 143 DNS Server Override softkey 20 DNS Server softkey 20 documentation ix Domain Name softkey 20 doublet softkeys 58 doublet adjustable 60 doublet trigger 60 Dual ARB player 68 softkeys 69 dual ARB real time noise 130 Dual ARB softkey 130 dwell time 29 153 Dwell Type softkey 29 dwell troubleshooting 146 Dynamic DNS Naming softkey 20 Dynamic Hostname Services softkey 20 E Edit softkeys Noise RMS Override 78 Repetitions 95 RMS 78 Selected Waveform Sequence 74 95 Editing Keys softkey 24 Editing Mode softkey 24 editor table 25 EEPROM 134 Enable Disable Markers softkey 74 95 entry active 153 ERR annunciator 8 Error hardkey 42 error messages 42 display area 8 file 148 message format 42 types 148 errors DAC over range 72 DAC over range 116 Esc hardkey 4 EVENT connector AUX I O 13 connector BNC 12 82 output jitter 97 outputs 82 EVM 153 EVM error 64 Execute Cal softkey 127 EXT CLOCK connector 12 EXT REF annunciator 7 8 Ext softkeys Dela
49. 21 More and LED 20 Return 18 Knob 19 Incr Set 15 Page Down 16 I Input 17 Q Input 12 RF Output 13 RF On Off and LED 14 Mod On Off and LED 7 MENUS and 10 Help 11 Preset and User Preset 9 Local Cancel Esc 5 Arrows and Select 6 Page Up 8 Trigger 4 Numeric Keypad 3 Softkeys 2 Display 1 Host USB MXG Vector Signal Generator N5181A 250 kHz 6 GHz 4 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Front Panel Overview 6 Page Up In a table editor use this hardkey to display a previous page See Example Using a Table Editor on page 25 When text does not fit on one page in the display area use this key in conjunction with the Page Down key page 5 to scroll text 7 MENUS These hardkeys open softkey menus that enable you to configure instrument functions or access information 8 Trigger When trigger mode is set to Trigger Key this hardkey initiates an immediate trigger event for a function such as a list or step sweep 9 Local Cancel Esc This hardkey deactivates remote operation and returns the signal generator to front panel control cancels an active function entry and cancels long operations such an IQ calibration 10 Help Use this key to display a description of any hardkey or softkey See Viewing Key Descriptions on page 23 11 Preset and User Preset These hardkeys set the signal generato
50. 29 Step Array 44 Step Sweep 27 28 Connection Monitoring softkey 20 connectors external triggering source 102 104 front panel 3 rear panel 9 routing signals 33 Continuous softkey 99 continuous step sweep example 32 continuous wave output 26 contrast adjustment 16 Contrast softkey 16 Copy File softkey 35 correction array user flatness 45 See also user flatness correction crossover cable 20 cursor 25 cw 153 CW no modulation softkey 29 D DAC over range error 72 DAC over range error 116 DAC over range errors 116 Dark Color softkey 16 data calibration 134 entry softkeys 24 erasing 136 files 35 38 removing 136 serial synchronizing 13 storage comments adding and editing 38 troubleshooting 147 type 41 using 35 date setting 18 dc offset 64 dc offset removing 55 DCFM DCfM Cal softkey 53 Default Gateway softkey 20 default settings restoring 17 system restoring 23 defaults restoring 20 127 delay I Q 125 Delete Row softkey 29 Delete softkeys All 35 All Files In Current Directory 41 All Regs in Seq 38 All Segments On Int Media 70 All Sequences 38 All Waveforms 74 All Waveforms softkey 95 File 35 File or Directory 36 41 Item 25 29 Row 25 Selected Waveform 74 95 Seq Reg 38 Waveform Sequence 95 Agilent N5181A 82A MXG Signal Generators User s Guide 157 Index DETHTR annunciator 7 Device softkey 26 DHCP 20 153 DHCP softkey
51. 5 PULSE 6 TRIG IN 7 TRIG OUT 8 REF IN 10 GPIB 11 LAN 12 Device USB 9 10 MHz OUT Digital Modulation Connectors vector models only on page 12 1 AC Power Receptacle Option 1EM only See page 5 10 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Rear Panel Overview 4 FM 5 PULSE 6 TRIG IN 7 TRIG OUT 8 REF IN In its factory default mode the signal generator can detect a valid reference signal at this connector and automatically switch from internal to external reference operation See Presetting the Signal Generator on page 23 With Option 1ER flexible reference input you must explicitly tell the signal generator the external reference frequency you wish to use enter the information through the front panel or over the remote interface Connector female BNC Impedance nominally 50 Signal An externally supplied 1Vp signal that produces the indicated deviation Damage Levels 5Vrms and 10Vp Connector female BNC Impedance nominally 50 Signal Externally supplied 1V on 0V off Damage Levels 5Vrms and 10Vp Connector female BNC Impedance high Z Signal An externally supplied TTL or CMOS signal for triggering operations such as point to point in manual sweep mode or an LF sweep in external sweep mode Triggering can occur on either the positive or negative edge Damage Levels 0 5V and 5 5V Connector female BN
52. 50Vdc 2W maximum RF power Connector Type female BNC Impedance 50 Signal An externally supplied analog in phase component of I Q modulation The signal level is 0 5 Vrms for a calibrated output level Damage Levels 1Vrms Connector Type female BNC Impedance 50 Signal An externally supplied analog quadrature phase component of I Q modulation The signal level is 0 5 Vrms for a calibrated output level Damage Levels 1Vrms 6 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Front Panel Overview 18 Knob Rotating the knob increases or decreases a numeric value or moves the highlight to the next digit character or item in a list See also Front Panel Knob Resolution on page 17 19 Incr Set This hardkey enables you to set the increment value of the currently active function The increment value also affects how much each turn of the knob changes an active function s value according to the knob s current ratio setting see Front Panel Knob Resolution on page 17 20 Return This hardkey enables you to retrace key presses In a menu with more than one level the Return key returns to the prior menu page 21 More and LED When a menu contains more softkey labels than can be displayed the More LED lights and a More message displays below the labels To display the next group of labels press the More hardkey 22 Power Switch and LEDs This s
53. 8 Each sample in the waveform is multiplied by 0 70588 to reach the 60 post scaling waveform amplitude Original ramp waveform Scaled ramp waveform Samples 120 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Scaling a Waveform 4 Name the copy this example uses the name MY_TEST_SCAL and press Enter Apply Scaling to the Copied Waveform File CAUTION This type of scaling is non reversible Any data lost in the scaling operation cannot be restored Save a copy of the waveform file before scaling 1 Open the DUAL ARB Waveform Utilities menu Press Mode gt Dual ARB gt More gt More gt Waveform Utilities 2 In the list of BBG Media segment files highlight the copied file in this example MY_TEST_SCAL 3 Set and apply a scaling value in this example 70 scaling is applied Press Scale Waveform Data gt Scaling gt 70 gt gt Apply to Waveform Agilent N5181A 82A MXG Signal Generators User s Guide 121 Basic Digital Operation Option 651 652 654 I Q Modulation I Q Modulation The following factors contribute to the error vector magnitude Differences in amplitude phase and delay between the I and Q channels DC offsets The I Q menu not only enables you to select the I Q signal source and output it also provides adjustments and calibrations to compensate for differences in the I and Q signals See also Modulating t
54. C Impedance nominally 50 Signal A TTL signal that is high at the start of a dwell sequence or when waiting for the point trigger in manual sweep mode It is low when the dwell is over or when the point trigger is received The logic polarity can be reversed This is a multiple use connector For signal routing selections see pages 33 and 57 Connector female BNC Impedance nominally 50 Signal An externally supplied 3 5 to 20 dBm signal from a timebase reference that is within 1 ppm Agilent N5181A 82A MXG Signal Generators User s Guide 11 Signal Generator Overview Rear Panel Overview 9 10 MHz OUT 10 GPIB This connector enables communication with compatible devices such as external controllers and is one of three connectors available to remotely control the signal generator see also 11 LAN and 12 Device USB 11 LAN The signal generator supports local area network LAN based communication through this connector which enables a LAN connected computer to remotely program the signal generator The LAN interface is LXI class C compliant it does not support auto MDIX The signal generator is limited to 100 meters on a single cable 100Base T For more information on the LAN refer to the Programming Guide 12 Device USB Use this universal serial bus USB connector to connect a PC to remotely control the signal generator Connector female BNC Impedance nominally 50 Signal A nominal si
55. Display softkey 16 active entry 153 entry area 7 function area 25 Active High softkey 99 Active Low softkey 99 Add Comment To softkey 38 additive white Gaussian noise See AWGN address GPIB 19 Adjust Phase softkey 26 Adjustable doublet softkey 58 adjustments I Q 64 quadrature 125 adjustments I Q 125 advance segment 101 Advanced Settings softkey 20 Agilent sales and service offices 151 ALC hold 83 84 OFF annunciator 7 off mode 47 softkeys 26 87 AM annunciator 7 connector 9 external source 55 hardkey 53 softkeys 53 amplitude display area 8 hardkey 26 modulation 53 offset 49 reference 50 setting 26 softkeys 26 29 troubleshooting sweep 146 AMPTD hardkey 26 Amptd softkeys 26 29 analog modulation 53 angle quadrature 64 annunciators 7 Apply To Waveform softkey 87 ARB definition 153 player dual 68 softkeys 68 97 130 waveform clipping 105 ARMED annunciator 7 arrow keys 24 ATTEN HOLD annunciator 7 Atten ALC Control softkey 26 Auto DHCP Auto IP softkey 20 Auto softkey 47 auto IP 20 AUX I O connector 13 Auxiliary Software Options softkey 21 AWGN adding 129 annunciator 7 definition 153 dual ARB player 130 softkeys 132 B backspace hardkey 24 Backup All User Files to Current Directory softkey 41 Bandwidth softkey 132 baseband 13 aligning signals at 83 clipping 105 frequency offset setting 72 I Q output connectors 12 me
56. EVEL The signal generator is unable to maintain the correct output level This is not necessarily an indication of instrument failure unleveled conditions can occur during normal operation Another annunciator ALC OFF appears in the same position when the ALC circuit is disabled see ALC OFF above UNLOCK Any of the phase locked loops cannot maintain phase lock To determine which loop is unlocked examine the error messages see Reading Error Messages on page 42 WINIT The signal generator is waiting for you to initiate a single sweep This annunciator appears when Agilent N5181A 82A MXG Signal Generators User s Guide 9 Signal Generator Overview Rear Panel Overview Rear Panel Overview 1 AC Power Receptacle The AC power cord receptacle accepts a three pronged AC power cord that is supplied with the signal generator For details on line setting requirements and the power cord see the Installation Guide 2 SWEEP OUT 3 AM Connector female BNC Can drive 2 k Impedance lt 1 Signal Voltage range 0 to 10V regardless of sweep width In swept mode beginning of sweep 0V end of sweep 10V In CW mode no output This is a multiple use connector For signal routing selections see pages 33 and 57 Connector female BNC Impedance nominally 50 Signal An externally supplied 1Vp signal that produces the indicated depth Damage Levels 5Vrms and 10Vp 2 SWEEP OUT 3 AM 4 FM
57. Interface 19 Configuring the LAN Interface 20 Enabling LAN Services Browser Sockets and VXI 11 20 Enabling an Option 21 Viewing Options and Licenses 21 3 Basic Operation Presetting the Signal Generator 23 Viewing Key Descriptions 23 Entering and Editing Numbers and Text 24 Entering Numbers and Moving the Cursor 24 Entering Alpha Characters 24 Example Using a Table Editor 25 Setting Frequency and Power Amplitude 26 Example Configuring a 700 MHz 20 dBm Continuous Wave Output 26 Configuring a S
58. M a Press AM b Set the AM type linear or exponential AM Type to highlight desired type c Set the depth AM Depth gt value gt d Set the rate AM Rate gt value gt frequency unit a Press FM M b Set the deviation FM Dev gt value gt frequency unit c Set the rate FM Rate gt value gt frequency unit a Press FM M gt FM M b Set the BW normal or high FM M to highlight desired type c Set the deviation M Dev gt value gt pi rad d Set the rate M Rate gt value gt frequency unit AM FM M AM Off On softkey to On FM Off On softkey to On M Off On softkey to On Agilent N5181A 82A MXG Signal Generators User s Guide 55 Using Analog Modulation Option UNT Only Using an External Modulation Source Using an External Modulation Source Removing a DC Offset To eliminate an offset in an externally applied FM or M signal perform a DCFM or DC M Calibration NOTE You can perform this calibration for internally generated signals but DC offset is not usually a characteristic of an internally generated signal 1 Set up and turn on the desired modulation 2 Press FM M gt More gt DCFM DC M Cal Performing the calibration with a DC signal applied removes any deviation caused by the DC signal and the applied DC level becomes the new zero reference point When you disconnect the DC signal perform the calibration again to reset the carrier to the corr
59. More gt Amptd Offset gt offset value gt dB Examples When using the signal generator as a local oscillator LO you can use the offset to display the frequency of interest as illustrated below Parameter Example 1 Example 2 Example 3 Comments Entered and displayed Value 300 MHz 300 MHz 2 GHz The entered value must be positive Offset 50 MHz 50 MHz 1 GHz An offset value can be positive or negative Output Frequency 250 MHz 350 MHz 3 GHz The signal generator alerts you if the output frequency or amplitude is out of range Indicates that an offset is on IF Amplifier RF Amplifier Mixer Filter Signal Generator local oscillator Output Frequency 1000 MHz IF 321 MHz Antenna tuned to 1321 MHz Selected Offset 321 MHz 679 MHz SIgnal Generator Display 1321 MHz Antenna Frequency 321 MHz IF Output IF Output 321 MHz 50 Agilent N5181A 82A MXG Signal Generators User s Guide Optimizing Performance Using an Output Offset Reference or Multiplier Setting an Output Reference Using an output reference the signal generator can output a frequency or amplitude that is offset positive or negative by the entered value from a chosen reference value RF Output reference value entered value To set a reference 1 Set the frequency or amplitude to the value you want as the output reference level 2 Frequency Press Frequency gt Freq Ref Set The frequency
60. N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Scaling a Waveform Scaling a Waveform The signal generator uses an interpolation algorithm sampling between the I Q data points when reconstructing a waveform For common waveforms this interpolation can cause overshoots which may create a DAC over range error condition This chapter describes how DAC over range errors occur and how you can use waveform scaling to eliminate these errors How DAC Over Range Errors Occur on page 116 How Scaling Eliminates DAC Over Range Errors on page 117 Agilent MXG waveform scaling on page 118 and page 119 Waveform runtime scaling to scale a currently playing waveform Waveform scaling to permanently scale either the currently playing waveform or a non playing waveform file in BBG media Agilent N5181A 82A MXG Signal Generators User s Guide 115 Basic Digital Operation Option 651 652 654 Scaling a Waveform Figure 8 13 Scaling Softkeys For details on each key use key help as described on page 23 Waveform Runtime Scaling see page 118 The settings in this menu can be stored to the file header see page 78 Waveform Scaling see page 119 116 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Scaling a Waveform How DAC Over Range Errors Occur The signal generator uses an interpolator filter when it
61. Operation Viewing Saving and Recalling Data Working with Instrument State Files Figure 3 5 Save and Recall Softkeys Example Saving an Instrument State 1 Preset the signal generator and set the following 2 Optional vector models only Associate a waveform file with these settings a Press Mode gt Dual ARB gt Select Waveform b Highlight the desired file and press Select Waveform If the file is not listed you must first move it from internal or external media to BBG media see page 71 3 Select the desired memory sequence for this example 1 Press Save gt Select Seq gt 1 gt Enter 4 Select the desired register in this example 01 Press Select Reg gt 1 gt Save Reg If a waveform is currently selected saving the instrument state also saves the waveform file name 5 Add a descriptive comment to sequence 1 register 01 Press Add Comment to Seq 1 Reg 01 enter the comment and press Enter The comment appears in the Saved States list when you press Recall If the instrument state has an associated waveform entering the waveform name makes it easy to identify which instrument state applies to which waveform The following information is not stored in a state file System Security Level List Mode Freq Hostname Remote Language FM Deviation System Security Level Display List Mode Power IP Address FTP Server PM Deviation System Security Level State List Mode Dwell Subnet Mask Manual
62. Oscillator Source softkey 26 reference using 50 references content of ix regrowth spectral 108 Remote Language softkey 19 remote operation annunciator 8 remote operation preferences 19 Rename File softkey 35 Rename Segment softkey 70 Reset amp Run softkey 99 Restart on Trig softkey 99 Restore softkeys All User Files from Current Directory 41 LAN Settings to Default Values 20 System Settings to Default Values 17 Return hardkey 6 Reverse Power Protection softkey 17 Revert to Default Cal Settings softkey 127 RF blanking marker function 93 settings saving 83 hardkey 5 output configuring 26 connector 5 troubleshooting 143 RF During Power Search softkey 47 RF Output softkey 121 122 123 RFC NETBIOS Naming softkey 20 ringing 116 ripple 116 RMS 154 rotary knob 24 Route Connectors softkey 27 58 Route To softkeys 33 58 routing I Q 64 121 marker ALC hold 84 RF blanking 93 saving settings 83 RPG test 149 runtime scaling 118 S S annunciator 8 sales Agilent offices 151 sample rate clock 13 sample rate softkey 97 Save hardkey 38 SAVE Seq Reg softkey 38 Save Setup To Header softkey 78 Scale Waveform Data softkey 115 scaling softkeys 115 SCPI enabling 20 reference content ix softkey 19 screen saver settings 16 Screen Saver softkey 16 search power 48 secure display 139 mode 137 softkey 35 security 133 Security softkey 35 Segment Advance softke
63. Text To terminate the entry press the Enter softkey A subset of this menu appears for hexadecimal characters The character menu displays only the letters A through F use the numeric keypad for other values Up down arrow keys increase decrease a selected highlighted numeric value and move the cursor vertically To specify a negative value enter the negative sign either before or after Backspace moves the cursor to the left deleting characters as it goes Left right arrow keys move the cursor horizontally Page up down keys move tables of data up and down within the display area Use the number keys and decimal point to enter numeric data Note Rotating the knob increases or decreases a numeric value changes a highlighted digit or character or steps through lists or items in a row See also Front Panel Knob Resolution on page 19 the numeric value this key is a toggle For details on each key see page 23 Use the Select hardkey to choose part of an entry as when entering alpha characters In some menus the Select key also acts as a terminator and is equivalent to the Enter softkey to move the cursor within the active value rather than within the alpha table turn the alpha table off Add edit comments for saved instrument state files see page 38 Note File names are limited to 25 characters Agilent N5181A 82A MXG Signal Generators User s Guide 25 Basic Operation Entering and Editin
64. User s Guide Agilent Technologies N5181A 82A MXG Signal Generators This guide applies to the following signal generator models N5181A MXG Analog Signal Generator N5182A MXG Vector Signal Generator Because of our continuing efforts to improve our products through firmware and hardware revisions signal generator design and operation may vary from descriptions in this guide We recommend that you use the latest revision of this guide to ensure that you have up to date product information Compare the print date of this guide see bottom of page with the latest revision which can be downloaded from the following website http www agilent com find mxg Manufacturing Part Number N5180 90003 Printed in USA September 2006 Copyright 2006 Agilent Technologies Inc ii Agilent N5181A 82A MXG Signal Generators User s Guide Notice The material contained in this document is provided as is and is subject to being changed without notice in future editions Further to the maximum extent permitted by applicable law Agilent disclaims all warranties either express or implied with regard to this manual and to any of the Agilent products to which it pertains 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 an
65. Waveform A vector signal generator with option 403 enables you to apply additive white gaussian noise AWGN to a carrier in real time while the modulating waveform plays in the dual ARB waveform player Figure 9 1 Real Time I Q Baseband AWGN Softkeys For the selected carrier to noise ratio the bandwidth over which the noise is integrated The amount of noise power relative to the carrier power For details on each key use key help as described on page 23 The state of the noise on or off is shown on the display The actual noise bandwidth which is typically slightly wider than the carrier bandwidth Agilent N5181A 82A MXG Signal Generators User s Guide 131 Adding Real Time Noise to a Signal Option 403 Adding Real Time Noise to a Dual ARB Waveform Use the following steps to modulate a 1 GHz 10 dBm carrier with the factory supplied waveform SINE_TEST_WFM and then apply 45 MHz bandwidth noise that has a 30 dB noise power carrier to noise ratio across a 40 MHz carrier bandwidth 1 Preset the signal generator and set the following Frequency 1 GHz Amplitude 10 dBm RF output on 2 Select the factory supplied waveform SINE_TEST_WFM a Press Mode gt Dual ARB gt Select Waveform b Highlight SINE_TEST_WFM and press Select Waveform 3 Turn on the dual ARB player press ARB Off On to highlight On 4 Set the ARB sample clock to 50 MHz Press ARB Setup gt ARB Sam
66. ader information without selecting a waveform or for another waveform than the one that is currently selected 1 Access the file header utilities menu Press Mode gt Dual ARB gt More gt More gt Header Utilities gt More gt Select Different Header The signal generator displays an alphabetical list of the waveform files in the media that was last selected The following figure shows an example of the factory supplied waveforms in BBG media 2 If the desired catalog is not displayed select it 3 Highlight the desired waveform file and press Select Header The signal generator displays the file header for the selected waveform file 4 To edit the header press More and proceed as described in Step 4 on page 80 Viewing and Modifying Header Information section Active waveform catalog Waveform sequences stored in internal or external media Waveforms segments stored in BBG media Active media Type WFM1 Volatile Segment NVWFM Non Volatile Segment SEQ Sequence Active catalog For details on each key use key help as described on page 23 Waveform segments stored in internal or external media 82 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Using Waveform Markers The signal generator provides four waveform markers to mark specific points on a waveform segment When the signal generator encounters an enabled marker
67. al Generator Memory 68 Dual ARB Player 68 Storing Loading and Playing a Waveform Segment 70 Storing Renaming a Waveform Segment to Non Volatile Memory Internal or External Media 70 Loading a Waveform Segment into BBG Media Volatile Memory 71 Playing a Waveform Segment 71 Setting the Baseband Frequency Offset 72 Waveform Sequences 74 Creating a Sequence 75 Viewing the Contents of a Sequence 76 Editing a Sequence 76 Playing a Sequence 77 Saving a Waveform s Settings amp Parameters 78 Viewing and Modifying Heade
68. al Generators User s Guide 59 Using Pulse Modulation Option UNU Pulse Characteristics Pulse Characteristics NOTE When using very narrow pulses that are below the signal generator s ALC pulse width specification or leveled pulses with an unusually long duty cycle it is often useful to turn ALC off see page 47 Pulse Source Type Perioda aAll delays widths and periods have a resolution of 10 ns Width amp Delaya Uses Trigger Eventb bA signal at the rear panel pulse connector must be held high for at least 20 ns to trigger an internally generated pulse Square Internal free run pulse train with 50 duty cycle Determined by user defined rate Free Run default Internal free run pulse train User Defined User Defined Triggered Internal pulse train User Defined Adjustable Doublet Two internal pulse trains for each trigger event User Defined First pulse is relative to the rising edge of trigger signal Second pulse is relative to the rising edge of first pulse See Figure 6 2 on page 60 Trigger Doublet Two internal pulse trains for each trigger event The first pulse follows the trigger signal Second pulse is user defined See Figure 6 3 on page 60 Gated Internal gated pulse train User Defined External External pulse signal at the rear panel Pulse connector External pulse input Rear panel i
69. amental operation See basic operation G Gated softkey 58 99 gated triggering 99 102 Gaussian See AWGN glossary 153 Go To Default Path softkey 36 41 Goto Row softkey 25 29 35 GPIB connector 11 definition 153 setup 19 GPIB Address softkey 19 GPIB Setup softkey 19 green LED 6 guides content of ix H hardkeys definition 153 help on 23 overview 3 See also specific key header utilities softkeys 78 Help hardkey 4 23 Hostname softkey 20 hostname setting 20 I I connector 5 I Offset softkey 125 I OUT connector 12 I O Config softkey 15 I Q adjustments 125 front panel inputs using 65 124 modulation 121 optimizing 122 rear panel outputs 12 rear panel outputs using 122 signal path optimizing 122 signal aligning 83 softkeys 64 121 127 waveform clipping 105 I Q adjustments 64 I Q modulation 64 IF 153 images 64 impairments 64 Import Waveform softkey 95 Incr Set hardkey 6 information removing from memory 136 Insert softkeys Insert 74 Item 25 29 Row 25 29 Waveform 74 Waveform Sequence Contents 74 installation guide content ix instrument firmware upgrading 18 Instrument softkeys Adjustments 15 Info 15 Options 21 instrument state associating with waveform 38 files 38 40 register See data storage Agilent N5181A 82A MXG Signal Generators User s Guide 159 Index int media 153 Int Phase Polarity softkey 121 interface GPIB 19 LAN
70. annel waveforms are random and generally result in a cancelling effect high power peaks occur infrequently with multiple channel summing Agilent N5181A 82A MXG Signal Generators User s Guide 107 Basic Digital Operation Option 651 652 654 Clipping a Waveform Combining the I and Q Waveforms When the I and Q waveforms combine in the I Q modulator to create an RF waveform the magnitude of the RF envelope is where the squaring of I and Q always results in a positive value As shown in the following figure simultaneous positive and negative peaks in the I and Q waveforms do not cancel each other but combine to create an even greater peak 108 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Clipping a Waveform How Peaks Cause Spectral Regrowth In a waveform high power peaks that occur infrequently cause the waveform to have a high peak to average power ratio as illustrated in the following figure Because the gain of a transmitter s power amplifier is set to provide a specific average power high peaks can cause the power amplifier to move toward saturation This causes the intermodulation distortion that generates spectral regrowth Spectral regrowth is a range of frequencies that develops on each side of the carrier similar to sidebands and extends into the adjacent frequency bands see the following figure Clipping provides a solution to this problem by reducing
71. ata bit The falling edge is used to clock external signals This signal is used with digital modulation applications Damage Levels gt 8 and lt 4V Maximum Clock Rate 50 MHz Connector female BNC Impedance nominally 50 Signal A pulse that can be used to trigger the start of a data pattern frame or timeslot Adjustable to one timeslot resolution one bit Markers Each Arb based waveform point has a marker on off condition associated with it Marker 1 level 3 3V CMOS high positive polarity selected 3 3V CMOS low negative polarity selected Output on this connector occurs whenever Marker 1 is on in an Arb based waveform see Using Waveform Markers on page 82 Damage Levels gt 8 and lt 4V I Q I Q Agilent N5181A 82A MXG Signal Generators User s Guide 13 Signal Generator Overview Rear Panel Overview PAT TRIG IN DIGITAL BUS I O This is a proprietary bus used by Agilent Technologies signal creation software This connector is not operational for general purpose use Signals are present only when a signal creation software option is installed for details refer to http www agilent com find signalcreation AUX I O Connector female BNC Impedance nominally 50 Signal A TTL CMOS low to TTL CMOS high or TTL CMOS high to TTL CMOS low edge trigger The input to this connector triggers the internal digital modulation pattern generator to start a single pattern output or t
72. ayed Frequency fRF 2200 MHz 2400 MHz Agilent N5181A 82A MXG Signal Generators User s Guide 53 5 Using Analog Modulation Option UNT Only Before using this information you should be familiar with the basic operation of the signal generator If you are not comfortable with functions such as setting the power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter The Basic Procedure on page 54 Using an External Modulation Source on page 55 Removing a DC Offset on page 55 Figure 5 1 Analog Modulation Softkeys See page 55 See page 55 See page 55 For details on each key use key help as described on see page 23 54 Agilent N5181A 82A MXG Signal Generators User s Guide Using Analog Modulation Option UNT Only The Basic Procedure The Basic Procedure 1 Preset the signal generator 2 Set the carrier RF frequency 3 Set the RF amplitude 4 Configure the modulation 5 Turn on the modulation The appropriate modulation annunciator displays indicating that you enabled modulation 6 Turn on the RF output The RF output LED lights indicating that the signal is transmitting from the RF output connector If the modulation does not seem to be working properly refer to No Modulation at the RF Output on page 143 See also Modulating the Carrier Signal on page 34 AM FM
73. column highlight the desired waveform sequence 3 Press Show Waveform Sequence Contents Editing a Sequence When editing a waveform sequence you can change the number of times each segment or nested sequence plays delete segments or nested sequences from the sequence add segments or nested sequences to the sequence toggle markers on and off described on page 95 save changes either to the current waveform sequence or as a new sequence If you exit the sequence editing menu before saving changes the changes are lost Sequences save to the Seq file catalog CAUTION If you edit and resave a segment used in a sequence the sequence does not automatically update the RMS value in its header You must select and update the sequence header information page 78 Use the following steps to edit a sequence that has two different segments so that the first segment repeats 100 times and the second segment repeats 200 times then save the changes Assumption A waveform sequence that has two different segments has been created and stored see previous example on page 75 1 Select the sequence Press Mode gt Dual ARB gt More gt More gt Waveform Sequences gt highlight the desired sequence gt Edit Selected Waveform Sequence 2 Change the first segment so that it repeats 100 times Highlight the first segment entry and press Edit Repetitions gt 100 gt Enter The cursor moves to the next entry 3
74. ctivates the ALC calibrates the power of the current RF output and then disconnects the ALC circuitry NOTE For the power search routine to execute RF must be on and ALC must be off Example Automatic Power Search 1 Preset the signal generator 2 Set the desired frequency 3 Set the desired amplitude 4 Turn the RF output on 5 Deactivate the signal generator s automatic leveling control Press AMPTD gt ALC Off On to highlight Off Deactivating the signal generator s automatic leveling control is a significant instrument change that automatically initiates a power search When set to Auto power search automatically executes when a significant instrument setting changes The Do Power Search feature enables you to execute a power search to compensate for other changes such as temperature drift or a change in the external input Agilent N5181A 82A MXG Signal Generators User s Guide 49 Optimizing Performance Using an Output Offset Reference or Multiplier Using an Output Offset Reference or Multiplier Setting an Output Offset Using an output offset the signal generator can output a frequency or amplitude that is offset positive or negative from the entered value RF Output entered value offset value Displayed Value output frequency offset value To set an offset Frequency Press Freq gt Freq Offset gt offset value gt frequency unit Amplitude Press Amptd gt
75. ctive Entry The currently selected and therefore editable entry or parameter ARB Arbitrary waveform generator AWG Arbitrary waveform generator Additive white Gaussian noise B BBG Media Baseband generator media Volatile memory where waveform files are played or edited BNC Connector Bayonet Neill Concelman connector A type of RF connector used to terminate coaxial cable C CCW Counterclockwise C N Carrier to noise ratio CW Continuous wave Clockwise D DHCP Dynamic host communication protocol Dwell Time In a step sweep see page 28 the time that the signal is settled and you can make a measurement before the sweep moves to the next point E EVM Error vector magnitude the magnitude of the vector difference at a given instant between the ideal reference signal and the measured signal G GPIB General purpose interface bus An 8 bit parallel bus common on test equipment H Hardkey A labeled button on the instrument I IF Intermediate frequency Int Media Internal media Non volatile signal generator memory where waveform files are stored IP Internet protocol The network layer for the TCP IP protocol suite widely used on Ethernet networks L LAN Local area network LO Local oscillator LXI LAN extension for instrumentation An instrumentation platform based on industry standard Ethernet technology designed to provide modularity flexibility and performance to small and
76. ding Error Messages on page 42 Presetting the Signal Generator Viewing Key Descriptions To return the signal generator to a known state press either Preset or User Preset Preset is the factory preset User Preset is a custom preset see also page 17 To reset persistent settings those unaffected by preset user preset or power cycle press Utility gt Power On Preset gt Restore System Defaults You can create more than one user preset by giving each saved state file a different name see Figure 3 6 on page 40 The Help hardkey enables you to display a description of any hardkey or softkey To display help text 1 Press Help 2 Press the desired key The help displays and the key s normal function does not execute 24 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Entering and Editing Numbers and Text Entering and Editing Numbers and Text Entering Numbers and Moving the Cursor Entering Alpha Characters Data entry softkeys appear in various menus If their meaning is not clear in context use the help key described on page 23 to display an explanation Use the softkey next to the alpha table for help on the table Selecting data that accepts alpha characters displays one of the menus shown at right Use the arrow keys or knob to highlight the desired letter then press the Select hardkey or the softkey next to the alpha table To correct errors use Bk Sp or Clear
77. e Type softkey 36 41 Store To File softkey 37 Subnet Mask softkey 20 Sum softkey 121 sweep annunciator 8 hardkey 27 linear 28 list parameters 30 list status information 30 logarithmic 28 manual control 33 out connector 9 33 out signal 33 softkeys 27 33 58 step 28 troubleshooting 146 waveform including 31 SWEEP hardkey 27 Sweep softkeys 27 33 58 swept output 27 switch power 6 SWMAN annunciator 8 system defaults restoring 17 T T annunciator 8 table editor 25 talker mode annunciator 8 TCP 154 TCP Keep Alive softkeys 20 terminator 154 test self 149 tests front panel 149 text area on display 8 text entry softkeys 70 time dwell 153 time setting 18 time date reference point 18 Time Date softkey 18 time based license troubleshooting 150 time based licenses cautions 18 Timer Trigger softkey 27 Toggle softkeys 95 Trig in connector 10 out connector 10 33 out signal 33 trigger connectors 10 hardkey 4 initiating 4 Trigger softkeys amp Run 99 Doublet 58 Key 27 Out Polarity 27 Source 98 Triggered 58 Type 98 Triggered softkey 58 triggering gated 99 102 segment advance 99 softkeys 98 waveforms 98 troubleshooting 141 Agilent N5181A 82A MXG Signal Generators User s Guide 163 Index U UNLEVEL annunciator 8 unleveled operation 47 UNLOCK annunciator 8 Unspecified softkey 78 Up Directory softkey 36 Update in Remote
78. e condition These codes are also used for self test response errors Errors in this class set the device specific error bit bit 3 in the event status register IEEE 488 2 section 11 5 1 The lt error_message gt string for a positive error is not defined by SCPI A positive error indicates that the instrument detected an error within the GPIB system within the instrument s firmware or hardware during the transfer of block data or during calibration Execution Errors 299 to 200 indicate that an error has been detected by the instrument s execution control block Errors in this class set the execution error bit bit 4 in the event status register IEEE 488 2 section 11 5 1 In this case Either a lt PROGRAM DATA gt element following a header was evaluated by the device as outside of its legal input range or is otherwise inconsistent with the device s capabilities or a valid program message could not be properly executed due to some device condition Execution errors are reported after rounding and expression evaluation operations are completed Rounding a numeric data element for example is not reported as an execution error Command Errors 199 to 100 indicate that the instrument s parser detected an IEEE 488 2 syntax error Errors in this class set the command error bit bit 5 in the event status register IEEE 488 2 section 11 5 1 In this case Either an IEEE 488 2 syntax error has be
79. e desired scale value to the determined absolute peak sample scale value multiplies each sample in the waveform file by this ratio When you scale a waveform you can create fractional data lose data or both Fractional data occurs almost every time you reduce or increase the scaling value and causes quantization errors Quantization errors are more noticeable when scaling down since you are closer to the noise floor You lose data when either the signal generator rounds fractional data down or the scaling value is derived using the results from a power of two This means that scaling a waveform in half power of two 21 2 causes each waveform sample to lose one bit The waveform data modifications are not correctable and may cause waveform distortion It is always best to make a copy of the original file prior to applying scaling Use the following examples to apply waveform scaling to a waveform file While this process uses the factory supplied waveform RAMP_TEST_WFM it is the same for any waveform file Copy a Waveform File 1 Display the waveform files in BBG media Press File gt Catalog Type gt More gt Volatile Segments 2 Highlight the waveform RAMP_TEST_WFM 3 Press Copy File Peak sample 85 of full scale Prescaling 60 of full scale Post scaling DAC full scale 100 Scaled sample value scaling ratio prescale sample val Scaling ratio desired scale val current scale val 60 85 0 7058
80. e page 78 88 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Viewing Waveform Segment Markers Markers are applied to waveform segments Use the following steps to view the markers set for a segment this example uses the factory supplied segment SINE_TEST_WFM 1 In the second Arb menu page 87 press Set Markers 2 Highlight the desired waveform segment in this example SINE_TEST_WFM 3 Press Display Waveform and Markers gt Zoom in Max The maximum zoom in range is 28 points Experiment with the Zoom functions to see how they display the markers The display can show a maximum of 460 points displayed waveforms with a sample point range greater than 460 points may not show the marker locations Clearing Marker Points from a Waveform Segment When you set marker points they do not replace points that already exist but are set in addition to existing points Because markers are cumulative before you set points view the segment page 88 and remove any unwanted points With all markers cleared the level of the event output signal is 0V To clear marker points on a segment the segment must reside in BBG media page 71 Clearing All Marker Points 1 In the second Arb menu page 87 press Set Markers 2 Highlight the desired waveform segment in this example SINE_TEST_WFM 3 Highlight the desired marker number Press Marker 1 2 3 4
81. e table row containing the cursor b Note the value measured by the power meter c Subtract the measured value from 0 dBm d Highlight the correction value in row 1 e Press Select gt the difference calculated in step c gt Enter The signal generator adjusts the output amplitude based on the correction value entered f If the power meter does not read 0 dBm adjust the value in step e until it does g Highlight the frequency value in the next row h Repeat steps b through g for this and the remaining rows The user flatness correction array title displays User Flatness without a name indicating that the current user flatness correction array data has not been saved to the file catalog Press Configure Step Array gt Freq Start gt 500 gt MHz gt Freq Stop gt 1 gt GHz gt of Points gt 10 gt Enter 46 Agilent N5181A 82A MXG Signal Generators User s Guide Optimizing Performance Using User Flatness Correction Optional Save the User Flatness Correction Data 1 Press Load Store gt Store to File 2 Enter a file name for this example FLATCAL1 and press Enter The user flatness correction array file is now stored in the file catalog as a UFLT file Any user flatness correction files saved to the catalog can be recalled loaded into the correction array and applied to the RF output to satisfy specific RF output flatness requirements 3 Press Return Enable the Flatness C
82. ect zero reference AM input Rear panel inputs are described on page 9 FM or M input Default Select to use external modulation Currently selected modulation 56 Agilent N5181A 82A MXG Signal Generators User s Guide Using Analog Modulation Option UNT Only Using an External Modulation Source Agilent N5181A 82A MXG Signal Generators User s Guide 57 6 Using Pulse Modulation Option UNU Before using this information you should be familiar with the basic operation of the signal generator If you are not comfortable with functions such as setting the power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter Pulse Characteristics on page 59 The Basic Procedure on page 61 Example on page 61 58 Agilent N5181A 82A MXG Signal Generators User s Guide Using Pulse Modulation Option UNU Figure 6 1 Pulse Softkeys See page 61 See page 61 Latency from the external pulse input to the pulse sync output 50 60 ns Width Period 50 ns gt 50 ns 20 ns 50 ns For details on each key use key help as described on page 23 Determines how the signal generator responds to an external pulse signal Normal high state Invert low state Low settled TTL signal See also page 9 and page 10 Select the signal that you want routed to each output connector Agilent N5181A 82A MXG Sign
83. ed for the desired power level at that point Turning ALC off is useful when the modulation consists of very narrow pulses that are below the pulse width specification of the ALC or when the modulation consists of slow amplitude variations that the automatic leveling would remove 1 Preset the signal generator 2 Set the desired frequency 3 Set the desired amplitude 4 Connect the power meter to the point at which you want a specific power level 5 Turn the RF output on 6 Deactivate the signal generator s automatic leveling control Press AMPTD gt ALC Off On to highlight Off 7 Adjust the signal generator s amplitude until the power meter measures the desired level Available only when ALC Off Available only when Power Search Span Available only when Power Search Span and Span Type User Auto The calibration routine executes whenever output frequency or amplitude changes Span Pressing Do Power Search executes the power search calibration routine once over a selected frequency range The corrections are stored and used whenever you tune the signal generator to within the calibrated frequency range For details on each key use key help as described on see page 23 48 Agilent N5181A 82A MXG Signal Generators User s Guide Optimizing Performance Using Unleveled Operating Modes Power Search Mode Refer to Figure 4 2 on page 47 Power search executes a routine that temporarily a
84. en a trigger is received subsequent triggers are ignored Plays the waveform when a trigger is received subsequent triggers restart the waveform The waveform stops during the inactive state of the trigger source and plays during the active state Ignores triggers received while a waveform is playing A trigger received while a waveform is playing waits until the current waveform completes then plays the waveform once more A trigger received while the waveform is playing immediately restarts the waveform A segment in a sequence plays once ignoring the repetition setting after which the dual ARB player stops and waits for a trigger before advancing to the next segment The next segment then plays to completion If a trigger is received while a segment is playing the segment plays to completion The dual ARB player then advances to the next segment and plays that segment to completion A segment in a sequence plays continuously until the waveform receives another trigger If a trigger is received while a segment is playing the segment plays to completion The dual ARB player then advances to the next segment and plays that segment continuously For details on each key use key help as described on page 23 100 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Triggering a Waveform Trigger Source External Trigger Polarity In Continuous Single
85. en detected by the parser a control to device message was received that is in violation of the IEEE 488 2 standard Possible violations include a data element that violates device listening formats or whose type is unacceptable to the device or an unrecognized header was received These include incorrect device specific headers and incorrect or unimplemented IEEE 488 2 common commands Error Message File A complete list of error messages is provided on the CDROM supplied with the instrument In the error message file an explanation is generally included with each error to further clarify its meaning The error messages are listed numerically In cases where there are multiple listings for the same error number the messages are in alphabetical order Agilent N5181A 82A MXG Signal Generators User s Guide 149 Troubleshooting Front Panel Tests Front Panel Tests Self Test The self test is a series of internal tests that checks different signal generator functions Set all display pixels to the selected color To return to normal operation press any key Blink RF On Off Mod on Off and More LEDs Correct operation Full CCW 10 Full CW 10 Displays a keyboard map As you press a key the map indicates the key location For details on each key use key help as described on page 23 It takes about 5 minutes to run the self test If a failure occurs 1 Ensure that all external cables including GPIB LAN
86. ence playback the segment headers are ignored except to verify that all required options are installed Storing a waveform sequence also stores its file header Some of the current signal generator settings shown in the file header appear as part of the softkey labels and others appear in the dual ARB summary display shown in the following example See page 79 Mode gt Dual ARB gt More gt More gt Header Utilities gt For details on each key use key help as described on page 23 ARB summary file header settings Softkey labels file header settings Softkey label file header setting All settings in this menu can be stored to the file header Agilent N5181A 82A MXG Signal Generators User s Guide 79 Basic Digital Operation Option 651 652 654 Saving a Waveform s Settings amp Parameters Viewing and Modifying Header Information The following example uses the factory supplied waveform file RAMP_TEST_WFM 1 From BBG media select the waveform RAMP_TEST_WFM a Press Mode gt Dual ARB gt Select Waveform b In the Segment On column highlight the waveform RAMP_TEST_WFM c Press Select Waveform 2 Open the Header Utilities menu Press More gt More gt Header Utilities The Figure 8 6 shows the default file header for the factory supplied waveform RAMP_TEST_WFM The Header Field column lists the file header parameters use the Page Down key to see them all The Saved Header S
87. enerators User s Guide Basic Digital Operation Option 651 652 654 I Q Modulation Configuring the Front Panel Inputs The signal generator accepts externally supplied analog I and Q signals through the front panel I Input and Q Input You can use the external signals as the modulating source or sum the external signals with the internal baseband generator signals 1 Connect I and Q signals to the front panel connectors a Connect an analog I signal to the signal generator s front panel I Input b Connect an analog Q signal to the signal generator s front panel Q Input 2 Set the signal generator to recognize the front panel input signals To Modulate onto the Carrier Press I Q gt I Q Source gt External To Sum and Modulate onto the Carrier Press I Q gt I Q Source gt Sum To select and play a waveform for the BB GEN path see page 71 Notice that only the internal BBG BB GEN routes I and Q signals to the rear panel I and Q outputs 3 If you are using only the external I and Q signals no summing turn on the I Q modulator Press I Q Off On to On 4 Configure the RF output a Set the carrier frequency b Set the carrier amplitude c Turn the RF output on Signal generator display both paths calibrated with I Q Correction Optimized Path set to Ext I Q Output see page 122 Signal generator display both RF paths calibrated with I Q Correction Optimized Path
88. enerators User s Guide Basic Operation Viewing Saving and Recalling Data Viewing a Stored File Files Stored in the Signal Generator 1 Press File gt Catalog Type gt desired catalog The files in the catalog appear in alphabetical order File information includes the file name type size modification date and time Files Stored on External Media 1 Connect the external media The instrument displays the External Media directory 2 Highlight the USER directory and press Select The file directories on the external media appear in alphabetical order as shown in the following figure Use the Page Up and Page Down keys to see the contents of the USER directory Agilent N5181A 82A MXG Signal Generators User s Guide 37 Basic Operation Viewing Saving and Recalling Data Saving and Recalling Data The method of storing and recalling data depends on the data An instrument state file contains instrument settings For this type of file use the Save and Recall hardkeys shown in Figure 3 5 on page 38 For other types of data use the Load Store softkeys shown below that are available through the menu used to create the file NOTE File names are limited to 25 characters Use this menu to enter the file name as described on page 24 For details on each key use key help as described on page 23 38 Agilent N5181A 82A MXG Signal Generators User s Guide Basic
89. ense 150 Contacting Agilent Technologies 151 Returning a Signal Generator to Agilent 151 Agilent N5181A 82A MXG Signal Generators User s Guide ix Documentation Overview Installation Guide Safety Information Receiving the Instrument Environmental amp Electrical Requirements Basic Setup Accessories Operation Verification Regulatory Information User s Guide Instrument Overview Front Panel Operation Security Basic Troubleshooting Programming Guide Remote Operation Status Registers Creating amp Downloading Files SCPI Reference SCPI Basics Command Descriptions Programming Command Compatibility Service Guide Troubleshooting Assembly Replacement Replaceable Parts Post Repair Procedures Safety and Regulatory Information Key Helpa aPress the Help hardkey and then the key for which you wish help Key function description Related SCPI commands x Agilent N5181A 82A MXG Signal Generators User s Guide Agilent N5181A 82A MXG Signal Generators User s Guide 1 1 Signal Generator Overview Signal Generator Features on page 2 Front Panel Overview on page 3 Fron
90. ent waveform selection Annunciators display with active waveform ARB On 72 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Setting the Baseband Frequency Offset Setting the Baseband Frequency Offset Figure 8 3 Baseband Frequency Offset Softkey The baseband frequency offset enables you to shift the baseband frequency up to 50 MHz within the BBG 100 MHz signal bandwidth depending on the signal generator s baseband generator option Common uses for the offset feature include offsetting the carrier from any LO feedthrough carrier signal spur at the carrier frequency sum the baseband signal with external I and Q inputs to create a multicarrier signal use the signal generator s I Q signal as an IF NOTE Changing the baseband frequency offset may cause a DAC over range condition that generates error 628 Baseband Generator DAC over range When this occurs reduce the waveform runtime scaling value page 114 The baseband frequency offset value is one of the file header parameters page 78 which means you can store this value with the waveform When you select a waveform with a stored frequency offset value the signal generator changes the current value to match the stored file header value If there is no stored baseband offset frequency value for the current waveform the signal generator uses the last set frequency offset value You can also use the Sa
91. er is Empty or Contains the Wrong State 147 External Media Data Storage 147 Instrument Recognizes External Media Connection but Does Not Display Files 147 Preset 147 The Signal Generator Does Not Respond 147 Pressing Preset Performs a User Preset 147 Error Messages 148 Error Message Types 148 Error Message File 148 Front Panel Tests 149 Self Test 149 Licenses 150 A Time Based License Quits Working 150 Cannot Load a Time Based Lic
92. eshooting RF Output RF Output No RF Output Check the RF ON OFF LED shown on page 3 If it is off press RF On Off to turn the output on Ensure that the amplitude is set within the signal generator s range If the instrument is playing a waveform ensure that marker polarity and routing settings are correct see Saving Marker Polarity and Routing Settings on page 83 Power Supply Shuts Down If the power supply does not work it requires repair or replacement If you are unable to service the instrument send the signal generator to an Agilent service center for repair see page 151 No Modulation at the RF Output Check both the Mod On Off LED and the lt modulation gt Off On softkey and ensure that both are on See also page 34 For digital modulation on a vector signal generator ensure that the internal I Q modulator is on the I Q annunciator displays If using an external modulation source ensure that the external source is on and that it is operating within the signal generator s specified limits RF Output Power too Low If the AMPLITUDE area of the display shows the OFFS indicator eliminate the offset Press Amptd gt More 1 of 2 gt Amptd Offset gt 0 gt dB See also Setting an Output Offset on page 49 If the AMPLITUDE area of the display shows the REF indicator turn off the reference mode 1 Press Amptd gt More gt Amptd Ref Off On until Off highligh
93. ettings column shows that most of the settings are Unspecified Unspecified means that there is no setting saved for that particular parameter The Current Inst Settings column shows the current signal generator settings In this example these are the settings that you will save to the file header NOTE If a setting is unspecified in the file header the signal generator uses its current value for that setting when you select and play the waveform Figure 8 6 Example File Header 3 Save the information in the Current Inst Settings column to the file header Press Save Setup To Header Both the Saved Header Settings column and the Current Inst Settings column now display the same values the Saved Header Settings column lists the settings saved in the file header The name of the waveform file The description can be up to 32 characters Mode gt Dual ARB gt More gt More gt Header Utilities gt Default header settings Current signal generator settings Resets the saved header settings entries to default settings 80 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Saving a Waveform s Settings amp Parameters 4 Edit and Update Settings a Return to the ARB Setup menu Press Return gt More gt ARB Setup From this menu you can access some of the signal generator settings that are saved to the file header Figure 8 1 on page 69 shows the ARB Setup
94. g Numbers and Text Example Using a Table Editor Table editors simplify configuration tasks The following procedure describes basic table editor functionality using the List Mode Values table editor 1 Preset the signal generator Press Preset 2 Open the table editor Press Sweep gt More gt Configure List Sweep The signal generator displays the editor shown in the following figure 3 Highlight the desired item use the arrow keys or the knob to move the cursor 4 Optional Display the selected item in the active function area Press Select 5 Modify the value If the value is displayed in the active function area use the knob arrow keys or numeric keypad to modify the value If the value is not displayed in the active function area use the numeric keypad to enter the desired value which then appears in the active function area 6 Terminate the entry If available press the desired units If units are not displayed press either Enter if available or Select The modified item is displayed in the table Cursor Table Editor Softkeys Table Editor Name Table Items Displays the active item as you edit it Highlighting indicates the selected item To make this the active editable item either press Select or simply enter the desired value Table items are also called data fields Used to load navigate modify and store table item values For details on each key use t
95. gh scaling maintains the basic shape of the waveform excessive scaling can compromise waveform integrity For example if the bit resolution becomes too low the waveform becomes corrupted with quantization noise To achieve maximum accuracy and optimize dynamic range scale the waveform no more than is required to remove the DAC over range error Optimum scaling varies with waveform content 118 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Scaling a Waveform Setting Waveform Runtime Scaling Runtime scaling scales the waveform data during playback it does not affect the stored data You can apply runtime scaling to either a segment or sequence and set the scaling value either while the ARB is on or off This type of scaling is well suited for eliminating DAC over range errors Runtime scaling adjustments are not cumulative the scaling value is applied to the original amplitude of the waveform file There are two ways to save the runtime scaling setting by using the save function page 35 and by saving the setting to the file header page 79 Saving to the file header saves the value with the waveform file saving with the Save function stores the value as the current instrument setting Use this example to learn how to scale the currently selected waveform 1 Select the waveform to which you want to apply scaling a Press Mode gt Dual ARB gt Select Waveform b Hig
96. ghlight the waveform RAMP_TEST_WFM 3 Press Copy File 4 Name the copy in this example the name is MY_TEST_CIRC and press Enter Apply Circular Clipping to the Copied Waveform File 1 Open the DUAL ARB Waveform Utilities menu Press Mode gt Dual ARB gt More gt More gt Waveform Utilities 2 In the list of files highlight the copied file in this example MY_TEST_CIRC 3 Create the CCDF plot Press Plot CCDF 4 Observe the shape and position of the waveform s curve the dark line in the example at right 5 Activate circular clipping Press Return gt Clipping gt Clipping Type until I jQ highlights 6 Set circular clipping to 80 Press Clip I jQ To gt 80 gt 7 Apply 80 clipping to the I and Q data Press Apply to Waveform 8 Create the CCDF plot see the example at right Press Plot CCDF 9 Observe the waveform s curve after clipping Note the reduction in peak to average power relative to the previous plot Example waveform curve before clipping Example waveform curve after circular clipping Agilent N5181A 82A MXG Signal Generators User s Guide 113 Basic Digital Operation Option 651 652 654 Clipping a Waveform Configuring Rectangular Clipping Use this example to configure rectangular clipping Rectangular clipping clips the I and Q data independently For more information about rectangular clipping refer to How Clipping Reduces Peak to Average
97. gnal level greater than 4 dBm Connector Mini B USB Protocol Version 2 0 12 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Rear Panel Overview Digital Modulation Connectors vector models only I OUT QOUT OUT OUT EXT CLOCK EVENT 1 Connector Type female BNC Impedance 50 DC coupled Signal I OUT The analog in phase component of I Q modulation from the internal baseband generator Q OUT The analog quadrature phase component of I Q modulation from the internal baseband generator OUT Used in conjunction with the I OUT connector to provide a balanceda baseband stimulus aBalanced signals are signals present in two separate conductors that are symmetrical relative to ground and are opposite in polarity 180 degrees out of phase OUT Used in conjunction with the Q OUT connector to provide a balanceda baseband stimulus Damage Levels gt 1 Vrms DC Origin Offset typically lt 10 mV Output Signal Levels into a 50 Load 0 5Vpk typical corresponds to one unit length of the I Q vector 0 69Vpk 2 84 dB typical maximum crest factor for peaks for 4 DQPSK alpha 0 5 0 71Vpk 3 08 dB typical maximum crest factor for peaks for 4 DQPSK alpha 0 35 Typically 1Vp p maximum Connector female BNC Impedance nominally 50 Signal An externally supplied TTL or CMOS bit clock signal where the rising edge aligns with the beginning d
98. he Carrier Signal on page 34 Figure 8 14 I Q Display and Softkeys These selections are reflected in the I Q Routing amp Optimization graphic page 125 This panel displays the current settings for the I Q signal routing and I Q correction optimized path This panel displays the current status and settings of the I Q adjustments Use the Page Up and Page Down keys to scroll through these parameters Grey indicates an inactive off adjustment Used only with internally generated bursted modulation formats Enables disables the RF burst modulator For details on each key use key help as described on page 23 Each path requires different optimization values when you select a path you are selecting the unique optimization values required by that path The signal generator applies the selected optimization values to both paths which impairs the unselected path Inverts an internally generated Q signal so that the I component lags the Q component by 90 degrees page 127 122 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 I Q Modulation Using the Rear Panel I and Q Outputs NOTE The rear panel I and Q connectors only output a signal while using the internal BBG In addition to modulating the carrier the signal generator also routes the internally generated I and Q signals to the rear panel I and Q connectors These output signals are post DAC so they a
99. he WINIT annunciator appears on the display indicating that the sweep is waiting to be initiated 3 If not already on turn the RF output on Press RF On Off 4 Initiate the sweep Press Single Sweep A single repetition of the configured sweep is available at the RF Output connector As the signal generator sweeps the SWEEP annunciator replaces WINIT on the display and the progress bar shows the progression of the sweep At the end of the single sweep there is no progress bar and the WINIT annunciator replaces SWEEP The empty entry is equivalent to choosing CW no modulation Agilent N5181A 82A MXG Signal Generators User s Guide 33 Basic Operation Configuring a Swept Output Example Manual Control of Sweep 1 Set up either a step sweep page 28 or a list sweep page 30 2 In the Sweep List menu select a parameter to sweep Press Sweep gt parameter 3 Select manual mode Press Return gt More gt Manual Mode Off On 4 If it is not already on turn the RF output on Press RF On Off 5 Select the point to output Press Manual Point gt number gt Enter 6 Use the knob or arrow keys to move from point to point Routing Signals Sweep gt More gt More gt Route Connectors gt The parameters of the selected sweep point define the signal available at the RF Output connector When you enter the manual point the progress bar moves to and stops at the selected point The SWMAN an
100. he key help Press the Help hardkey and then the desired key Active Function Area Current Total Number of Pages Indicates that another menu is available to display the second menu press More vector models only 26 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Setting Frequency and Power Amplitude Setting Frequency and Power Amplitude Figure 3 1 Frequency and Amplitude Softkeys Example Configuring a 700 MHz 20 dBm Continuous Wave Output 1 Preset the signal generator The signal generator displays its maximum specified frequency and minimum power level the front panel display areas are shown on page 7 2 Set the frequency to 700 MHz Press Freq gt 700 gt MHz The signal generator displays 700 MHz in both the FREQUENCY area of the display and the active entry area 3 Set the amplitude to 20 dBm Press Amptd gt 20 gt dBm The display changes to 20 dBm in the AMPLITUDE area of the display and the amplitude value becomes the active entry Amplitude remains the active function until you press another function key 4 Turn on the RF Output Press RF On Off The RF Output LED lights and a 700 MHz 20 dBm CW signal is available at the RF OUTPUT connector See page 47 Option 1ER only To display the next menu press More page 44 For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generato
101. he signal generator can no longer use time based licenses Time Current time date reference point gt 25 hours Agilent N5181A 82A MXG Signal Generators User s Guide 19 Setting Preferences amp Enabling Options Remote Operation Preferences Remote Operation Preferences For details on operating the signal generator remotely refer to the Programming Guide Configuring the GPIB Interface page 20 Below page 20 NOTES USB is also available It is not shown in the menu because it requires no configuration For details on using the instrument remotely see the Programming Guide Select the desired GPIB language Utility gt I O Config gt For details on each key use key help as described on page 23 20 Agilent N5181A 82A MXG Signal Generators User s Guide Setting Preferences amp Enabling Options Remote Operation Preferences Configuring the LAN Interface Enabling LAN Services Browser Sockets and VXI 11 NOTES Use a 100Base T LAN cable to connect the signal generator to the LAN Use a crossover cable to connect the signal generator directly to a PC For details on using the instrument remotely see the Programming Guide Utility gt I O Config gt See page 20 Listed in the Programming Guide Enable remote browser access to the instrument s file system Use a browser to control the signal generator Utility gt I O Config gt For details on each key use key help
102. he signal generator displays the menu shown in the figure below and the message External USB Storage attached When you disconnect the USB media the message External USB Storage detached displays When you open the External Media menu without USB media connected the signal generator displays the message External Media Not Detected The signal generator does not format external media create directories or change file permissions Use a computer to perform these operations Non Volatile Storage Int Internal Ext External if a memory stick is not connected non volatile storage is not available Auto External if present otherwise internal is used File gt More gt External Media File Manager gt File Type List State Waveform User Flatness User Preset License Extension list state waveform uflat uprst lic Save From Sweep menu Save menu Mode menu Amplitude menu User Preset menu Agilent purchase Pressing Select with file highlighted loads list and starts sweep load instrument state loads and plays waveform loads and applies user flatness loads and executes user preset installs purchased license Requires confirmation File Length including extension Internal Media 25 characters External Media 39 characters To navigate the directory use the Select hardkey and the Up Directory softkey Deletions backups and restores require confirmation To set the directory that the signal ge
103. he softkeys located immediately to the right of the display Softkey labels change depending on the function selected DIGBUS The digital bus is in use ERR An error message is placed in the error queue This annunciator does not turn off until you either view all of the error messages or clear the error queue see Reading Error Messages on page 42 EXTREF An external frequency reference is applied FM Frequency modulation is on If you turn phase modulation on the M annunciator replaces FM I Q I Q vector modulation is on L The signal generator is in listener mode and is receiving information or commands over the GPIB USB or VXI 11 Sockets LAN interface MULT A frequency multiplier is set see Setting a Frequency Multiplier on page 51 OFFS An output offset is set see Setting an Output Offset on page 49 PULSE Pulse modulation is on R The signal generator is remotely controlled over the GPIB USB or VXI 11 Sockets LAN interface REF An output reference is set see Setting an Output Reference on page 50 S The signal generator has generated a service request SRQ over the GPIB USB or VXI 11 Sockets LAN interface SWEEP The signal generator is currently sweeping in list or step mode SWMAN The signal generator is in manual sweep mode T The signal generator is in talker mode and is transmitting information over the GPIB USB or VXI 11 Sockets LAN interface UNL
104. hlight the desired waveform segment or sequence c Press Select Waveform 2 Play the selected waveform Press ARB Off On until On highlights 3 Set the Waveform Runtime Scaling value a Press ARB Setup gt Waveform Runtime Scaling b Enter a scaling value The signal generator automatically applies the new scaling value to the waveform There is no single value that is optimal for all waveforms To achieve the maximum dynamic range use the largest scaling value that does not result in a DAC over range error c Press Return Agilent N5181A 82A MXG Signal Generators User s Guide 119 Basic Digital Operation Option 651 652 654 Scaling a Waveform Setting Waveform Scaling Waveform scaling differs from waveform runtime scaling in that it permanently affects waveform data and only applies to waveform segments stored in BBG media You scale the waveform either up or down as a percentage of the DAC full scale 100 If you scale your waveforms using this method you may also need to change the waveform runtime scaling value to accommodate this scaling When you scale the signal generator permanently modifies the waveform file s sample values so that they conform to the desired scaling value When you initiate scaling the signal generator performs the following actions locates the waveform file s absolute peak sample value determines its current percentage of full scale calculates the ratio of th
105. ics on page 68 Storing Loading and Playing a Waveform Segment on page 70 Setting the Baseband Frequency Offset on page 72 Waveform Sequences on page 74 Saving a Waveform s Settings amp Parameters on page 78 Using Waveform Markers on page 82 Triggering a Waveform on page 98 Clipping a Waveform on page 105 Scaling a Waveform on page 114 I Q Modulation on page 121 See Also Adding Real Time Noise to a Dual ARB Waveform on page 130 68 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Waveform File Basics Waveform File Basics There are two types of waveform files A segment is a waveform file that you download to the signal generator For information on creating and downloading waveform files refer to the Programming Guide A sequence is a file you create in the signal generator that contains pointers to one or more waveform files segments other sequences or both For information on creating sequences see page 74 Signal Generator Memory The signal generator has two types of memory Volatile memory baseband generator BBG media where waveform files are played from or edited Non volatile memory either internal int or external USB media where waveform files are stored Dual ARB Player The dual ARB waveform player enables you to play rename delete store and load
106. ier Reverse power problems can be solved by using one of the unleveled operating modes See ALC Off Mode on page 47 and Power Search Mode on page 48 Signal Loss While Working with a Mixer To fix signal loss at the signal generator s RF output during low amplitude coupled operation with a mixer add attenuation and increase the RF output amplitude The figure at right shows a configuration in which the signal generator provides a low amplitude signal to a mixer The internally leveled signal generator RF output and ALC level is 8 dBm The mixer is driven with an LO of 10 dBm and has an LO to RF isolation of 15 dB The resulting 5 dBm LO feedthrough enters the signal generator s RF output connector and arrives at the internal detector Depending on frequency it is possible for most of this LO feedthrough energy to enter the detector Because the detector responds to its total input power regardless of frequency this excess energy causes the ALC to reduce the RF output In this example the reverse power across the detector is actually greater than the ALC level which can result in loss of signal at the RF output Mixer LO ALC Level 8 dBm RF Level Control Signal Generator Output Control Detector measures 8 dBm ALC level Detector measures 5 dBm reverse power LO Feedthru 5 dBm RF Output 8 dBm LO Level 10 dBm IF Effect
107. ile memory For information on loading waveform segments into BBG media see page 71 1 Select the first segment a Press Mode gt Dual ARB gt More gt More gt Waveform Sequences gt Build New Waveform Sequence gt Insert Waveform b Highlight the desired waveform segment and press Insert 2 Select the second segment a Highlight the next desired waveform segment and press Insert b Press Done Inserting 3 Name and store the waveform sequence to the Seq file catalog a Press More gt Name and Store b Enter a file name and press Enter See also Viewing the Contents of a Sequence on page 76 and Setting Marker Points in a Waveform Segment on page 89 Waveform Sequence Sequence A Sequence B Sequence A repeated 4x Segment 1 Segment 2 Segment 3 2 segments 9 segments 11 segments 8 Segments 76 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Waveform Sequences Viewing the Contents of a Sequence There are two ways to view the contents of a waveform sequence through the Waveform Sequences softkey or the Select Waveform softkey Waveform Sequences Softkey 1 Press Mode gt Dual ARB gt More gt More gt Waveform Sequences 2 Highlight the desired sequence 3 Press Show Waveform Sequence Contents Waveform Select Softkey 1 Press Mode gt Dual ARB gt Select Waveform 2 In the Sequence On
108. ing defaults 17 Phase Ref Set softkey 26 phase skew 64 pixel test 149 Plot CDDF softkey 115 Point Trigger softkey 27 point to point time 153 polarity external trigger 100 polarity marker setting 94 power meter 44 45 on settings 17 peak to average reducing 109 receptacle 9 search 48 setting 26 softkeys 15 17 26 29 47 supply troubleshooting 143 switch 6 troubleshooting 143 Power softkeys On 17 On Preset 15 Search 47 preferences setting 15 preset hardkey location 4 settings 17 troubleshooting 147 using 23 Preset softkeys Language 17 List 29 44 Preset 17 Proceed With Reconfiguration softkey 20 programming guide content ix pulse annunciator 8 characteristics 59 connector 10 marker viewing 92 modulation 57 narrow 47 sync signal 33 video signal 33 Pulse hardkey 58 Pulse softkeys 33 58 Pulse RF Blank softkey 87 Q Q connector 5 Q Offset softkey 125 quadrature adjustment 125 quadrature angle 64 Quadrature Angle Adjustment softkey 64 125 Agilent N5181A 82A MXG Signal Generators User s Guide 161 Index queue error 42 R R annunciator 8 RAM 134 135 Real Time I Q Baseband AWGN softkeys 132 real time noise 130 Real time Noise softkeys 130 rear panel I Q outputs 122 rear panel overview 9 Recall hardkey 38 recall register troubleshooting 146 rectangular clipping 110 113 REF annunciator 8 REF IN connector 10 Ref
109. ip as main flash memory but managed separately During normal operation this memory cannot be overwritten It is only overwritten during the firmware installation or upgrade process Because this memory chip contains 8 MB of user data and 8 MB of firmware memory described here a full chip erase is not desirable User data areas are selectively and completely sanitized when you perform the Erase and Sanitize function Bootrom Memory EEPROM 8 kB No Yes CPU bootup parameters no user data factory programmed CPU board During normal operation this memory cannot be overwritten or erased This read only data is programmed at the factory Calibration Data Flash 256 kB No Yes factory calibration configuration data backup no user data factory or service only RF Board LCD Display Memory RAM 160 kB No No display buffer operating system RF board Agilent N5181A 82A MXG Signal Generators User s Guide 135 Working in a Secure Environment Understanding Memory Types Front Panel Memory Flash 32 kB No No front panel keyboard controller firmware no user data operating system Front Panel board aAnalog instruments only Table 10 2 Baseband Generator Memory Options 651 652 654 Memory Type and Size Writable During Normal Operation Data Retained When Powered Off Purpose Contents Data Input Method Remarks Waveform Memory RAM 320 MB Yes No
110. ital Operation Option 651 652 654 Triggering a Waveform Example External Triggering Use the following example to set the signal generator to output a modulated RF signal 100 milliseconds after a change in TTL state from low to high occurs at the PATT TRIG IN rear panel BNC connector 1 Connect the signal generator to the function generator as shown above 2 Configure the RF output Set the desired frequency Set the desired amplitude Turn on the RF output 3 Select a waveform for playback sequence or segment a Press Mode gt Dual ARB gt Select Waveform b In the Segment On or Sequence On column highlight a waveform c Press Select Waveform 4 Generate the waveform Press ARB Off On until On highlights 5 Set the waveform trigger as follows a Trigger Type single Press Trigger Type gt Single gt No Retrigger b Trigger Source external Press Trigger Source gt Ext c Input connector Rear panel Patt Trig In BNC Press Ext Source gt Patt Trig In 1 d External Trigger Polarity positive Press Ext Polarity until Pos highlights e External Delay 100 ms Press More gt Ext Delay until On highlights Press Ext Delay Time gt 100 gt msec 6 Configure the Function Generator Waveform 0 1 Hz square wave Output Level 3 5V to 5V Agilent N5181A 82A MXG Signal Generators User s Guide 105 Basic Digital Operation Option 651 652 654 Clipping a Wavef
111. m b In the Sequence On column highlight a waveform sequence file c Press Select Waveform 4 Set the triggering as follows Trigger Type continuous Segment Advance Press Trigger Type gt Segment Advance gt Continuous Trigger source Trigger hardkey Press Trigger Source gt Trigger Key 5 Generate the waveform sequence Press ARB Off On until On highlights 6 Optional Monitor the waveform Connect the RF OUTPUT of the signal generator to the input of an oscilloscope and configure the oscilloscope so that you can see the signal 7 Trigger the first waveform segment to begin playing continuously Press the Trigger hardkey 8 Trigger the second segment Press the Trigger hardkey Pressing the Trigger hardkey causes the currently playing segment to finish and the next segment to start If the last segment in the sequence is playing pressing the Trigger hardkey causes the first segment in the waveform sequence to start when the last segment finishes 102 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Triggering a Waveform Example Gated Triggering Gated triggering enables you to define the on and off states of a modulating waveform 1 Connect the output of a function generator to the signal generator s rear panel PATT TRIG IN connector as shown in the following figure This connection is applicable to all external triggering
112. methods The optional oscilloscope connection enables you to see the effect that the trigger signal has on the RF output 2 Preset the signal generator 3 Configure the RF output Set the desired frequency Set the desired amplitude Turn on the RF output 4 Select a waveform for playback sequence or segment a Press Mode gt Dual ARB gt Select Waveform b In the Segment On or Sequence On column highlight a waveform c Press Select Waveform 5 Set the triggering as follows Trigger type Gated Press Trigger Type gt Gated Active state Low Press Active Low Trigger source External Press Trigger Source gt Ext Input connector Rear panel Patt Trig In BNC Press Ext Source gt Patt Trig In 1 6 Generate the waveform Press Return gt ARB Off On until On highlights Agilent N5181A 82A MXG Signal Generators User s Guide 103 Basic Digital Operation Option 651 652 654 Triggering a Waveform 7 On the function generator configure a TTL signal for the external gating trigger 8 Optional Monitor the waveform Configure the oscilloscope to display both the output of the signal generator and the external triggering signal You will see the waveform modulating the output during the gate active periods low in this example The following figure shows an example display 104 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Dig
113. mory 68 134 noise 129 noise annunciator 7 quadrature adjustment 125 real time I Q AWGN 130 132 softkey 72 summing signals 124 waveforms convert to analog 116 Baseband Frequency Offset softkey 72 BB GEN 124 BBG 124 BBG media 68 71 153 Binary softkey 35 Bk Sp hardkey 24 BNC 153 bootrom memory 134 Bright Color softkey 16 156 Agilent N5181A 82A MXG Signal Generators User s Guide Index brightness adjustment 16 Brightness softkey 16 Buffered Trig softkey 99 Build New Waveform Sequence softkey 74 95 Burst Envelope softkey 121 Bus softkey 27 C C N 153 cables 100Base T LAN 20 cables crossover 20 Calculate softkey 78 calibration data 134 calibration data memory 135 Calibration Type softkey 127 calibration I Q 127 Cancel hardkey 4 carrier bandwidth 130 configuring 26 modulating 34 to noise ratio 130 Carrier Bandwidth softkey 130 carrier feedthrough 64 Carrier to Noise softkey 130 Catalog Type softkey 35 78 catalog state files 40 ccw 153 Channel Band softkey 26 Channel Number softkey 26 circular clipping 109 112 classified See security Clear Error Queue s softkey 42 Clear Header softkey 78 Clear Text softkey 24 clipping circular 109 112 rectangular 110 113 softkeys 105 clock sample rate 13 color palette display 16 comments adding amp editing instrument state 38 Config Type softkey 20 Configure softkeys Cal Array 44 List Sweep 27
114. n turn it off Editing list sweep parameters with sweep on can generate an error 3 Set the sweep type to list Press SWEEP gt Sweep Type List Step to highlight List 4 In the List Mode Values table editor change the point 1 dwell time defined in row 1 to 100 ms a Press More gt Configure List Sweep b Highlight the point 1 dwell time c Press 100 gt msec The next item in the table the frequency value for point 2 highlights 5 Change the selected frequency value to 445 MHz Press 445 gt MHz 6 Add a new point between points 4 and 5 Highlight any entry in row 4 and press Insert Row This places a copy of row 4 below row 4 creating a new point 5 and renumbers subsequent rows 7 Shift frequency values down one row beginning at point 5 Highlight the frequency entry in row 5 then press More gt Insert Item This shifts the original frequency values for rows 5 and 6 down one row and creates an entry for row 8 that contains only a frequency value the power and dwell time entries do not shift down 8 Change the still active frequency value in row 5 to 590 MHz Press 590 gt MHz The power in row 5 is now the active parameter 9 Insert a new power value 2 5 dBm for point 5 and shift down the original power values for points 5 and 6 by one row Press Insert Item gt 2 5 gt dBm 10 To complete the entry for point 8 insert a duplicate of the point 7 dwell time by shifting a copy of the
115. ncy ranges see page 46 Figure 4 1 User Flatness Correction Softkeys Basic Procedure 1 Create a user flatness array Enter the user flatness correction values 2 Optionally save the user flatness correction data 3 Apply user flatness correction to the RF Output Confirm For details on each key use key help as described on see page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 45 Optimizing Performance Using User Flatness Correction Example A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction Values Create the User Flatness Array 1 Configure the signal generator a Preset the signal generator b Open the User Flatness table editor and preset the cal array Press Amptd gt More gt User Flatness gt Configure Cal Array gt More gt Preset List gt Confirm Preset c In the Step Array menu enter the desired flatness corrected frequencies d Populate the user flatness correction array with the step array configured in the previous step Press Return gt Load Cal Array From Step Array gt Confirm Load From Step Data e Set the output amplitude to 0 dBm f Turn on the RF output 2 Connect the power meter to the RF output and manually enter the correction values a Open the User Flatness table editor and highlight the frequency value in row 1 Press More gt User Flatness gt Configure Cal Array The RF output changes to the frequency value of th
116. ndards To Start Press File gt More gt Security gt Erase and Sanitize All gt Confirm Sanitize Secure Mode CAUTION Once you activate secure mode by pressing Confirm you cannot deactivate or decrease the security level the erasure actions for that security level execute at the next power cycle Once you activate secure mode you can only increase the security level until you cycle power For example you can change Erase to Overwrite but not the reverse After the power cycle the security level selection remains the same but secure mode is not activated Secure mode automatically applies the selected Security Level action the next time the instrument s power cycles To Set the Level Press File gt More gt Security gt Security Level and choose from the following None factory preset no user information is lost Erase Erase All Overwrite Erase and Overwrite All Sanitize Erase and Sanitize All To Activate Press File gt More gt Security gt Enter Secure Mode gt Confirm The softkey changes to Secure Mode Activated CPU Flash Overwrites all addressable locations with random characters and then erases the flash blocks This accomplishes the same purpose as a chip erase System files are restored after erase BBG Persistent Memory Flash Vector instruments only Overwrites all addressable locations with random characters and then erases the flash blocks This accomplishes the
117. nerator Changes the absolute phase of both the I and Q signals with respect to triggers and markers Positive values add delay and negative values advance the signals This value affects both the baseband signal modulated onto the RF and the external output signals I and Q This setting cannot be used with constant envelope modulation and it does not affect external I and Q inputs Offsets are typically used to either reduce carrier leakage or to create an impairment that simulates carrier leakage Common Mode I Q Offset This adjusts the DC offset of both I and Q signals simultaneously Diff Mode I Offset This adjusts the DC offset level of the I and I bar output signal I and I bar cannot be adjusted independently Diff Mode Q Offset This adjusts the DC offset level of the I and I bar output signal I and I bar cannot be adjusted independently 126 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 I Q Adjustments The I Q adjustment I Q Delay is not for adding impairments its function is to compensate for any latency between the EVENT output signals marker signals and the RF output Table 8 1 I Q Adjustments Uses I Q Adjustment Effect Impairment Offset Carrier feedthrough dc offset Quadrature Angle EVM error phase skew I Q Images I Q path delay I Q Skew EVM error high sample rate phase skew or I Q path delay I Q Gain Balance I Q amplitude diffe
118. nerator will use on the external media 1 Navigate to the directory It will display in the path 2 Press this softkey 42 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Reading Error Messages Reading Error Messages If an error condition occurs the signal generator reports it to both the front panel display error queue and the SCPI remote interface error queue These two queues are viewed and managed separately for information on the SCPI error queue refer to the Programming Guide Error Message Format In the front panel display error queue error messages display on an enumerated 1 of N basis Characteristic Front Panel Display Error Queue Capacity errors 30 Overflow Handling Drops the oldest error as each new error comes in Viewing Entries Press Error gt View Next or Previous Error Page Clearing the Queue Press Error gt Clear Error Queue s Unresolved Errorsa aErrors that must be resolved For example unlock Re reported after queue is cleared No Errors When the queue is empty every error in the queue has been read or the queue is cleared the following message appears in the queue No Error Message s in Queue 0 of 0 Error Number Error Message Error Description May be truncated on the display 222 Data out of range value clipped to lower limit Indicates that the user has entered a deviation depth or internal source frequency that
119. not have a marker file associated with it causes the signal generator to automatically create a marker file but does not place any marker points Marker Point Edit Requirements Before you can modify a waveform segment s marker points the segment must reside in BBG media see Loading a Waveform Segment into BBG Media Volatile Memory on page 71 Saving Marker Polarity and Routing Settings Marker polarity and routing settings remain until you reconfigure them preset the signal generator or cycle power To ensure that a waveform uses the correct settings when it is played set the marker polarities or routing RF Blanking and ALC Hold and save the information to the file header page 78 NOTE When you use a waveform that does not have marker routings and polarity settings stored in the file header and the previously played waveform used RF Blanking ensure that you set RF Blanking to None Failure to do so can result in a no RF output condition or a distorted Marker File Bit N Marker Polarity Marker N RF Blank Off On Marker N Blanks RF when Marker is Low EVENT N Negative Positive Set Marker On Off Marker N ALC Hold Off On Marker N Holds ALC when Marker is Low When the signal generator encounters an enabled marker described on page 95 an auxiliary output signal is generated and routed to the rear panel Event 1 is available at the EVENT 1 BNC connector see page 12 and at a pin on the
120. nputs are described on page 9 60 Agilent N5181A 82A MXG Signal Generators User s Guide Using Pulse Modulation Option UNU Pulse Characteristics Figure 6 2 Adjustable Doublet Figure 6 3 Trigger Doublet The delay of the first pulse is measured from the leading edge of the external trigger signal Delay Width RF Output External Trigger The delay of the second pulse is measured from the leading edge of the first pulse Delay Width The delay of the second pulse is measured from the leading edge of the external trigger signal Delay Width RF Output External Trigger The first pulse follows the external trigger signal Agilent N5181A 82A MXG Signal Generators User s Guide 61 Using Pulse Modulation Option UNU The Basic Procedure The Basic Procedure 1 Preset the signal generator 2 Set the carrier RF frequency 3 Set the RF amplitude 4 Configure the modulation a Set the pulse source Press Pulse gt Pulse Source gt selection b Set the parameters for the selected pulse source 5 Turn on the modulation Pulse Off On softkey to On The the PULSE annunciator lights indicating that you enabled modulation 6 Output the modulated signal from the signal generator Press the front panel RF On Off key The RF output LED lights indicating that the signal is transmitting from the RF output connector See also Modulating the Carrier Signal on page 34 Example
121. nunciator indicates that the sweep is in manual mode Select the signal that you want routed to each output connector For details on each key use key help as described on page 23 34 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Modulating the Carrier Signal Modulating the Carrier Signal To modulate the carrier signal you must have both an active modulation format and modulation of the RF output enabled Example 1 Preset the signal generator 2 Turn on AM modulation Press AM gt AM Off On requires Option UNT You can turn on the modulation format before or after setting signal parameters The modulation format generates but does not yet modulate the carrier signal Once the signal generates an annunciator showing the name of the format appears indicating that a modulation format is active 3 Enable modulation of the RF output Press the Mod On Off key until the LED lights If you enable modulation without an active modulation format the carrier signal does not modulate until you subsequently turn on a modulation format NOTE To turn modulation off press the Mod On Off key until the LED turns off When the Mod On Off key is off the carrier signal is not modulated even with an active modulation format 4 To make the modulated carrier available at the RF output connector press the RF On Off key until the LED lights See also Using Analog Modulati
122. o stop and re synchronize a pattern that is being continuously output To synchronize the trigger with the data bit clock the trigger edge is latched then sampled during the falling edge of the internal data bit clock This is the external trigger for all ARB waveform generator triggers Minimum Trigger Input Pulse Width high or low 100 ns Minimum Trigger Delay trigger edge to first bit of frame 1 5 to 2 5 bit clock periods Damage Levels gt 8 and lt 4V View looking into rear panel female 50 pin connector 25 1 26 50 Pin 1 Event 1 Pin 2 Event 2 Pin 3 Event 3 Pin 4 Event 4 Pin 5 Sample Rate Clock Out Pin 6 Patt Trig In 2 Pins 7 25 Reserved Pins 26 50 Ground Future Capability Event 1 2 3 and 4 pins 1 4 A pulse that can be used to trigger the start of a data pattern frame or timeslot Adjustable to one timeslot resolution one bit Markers Each Arb based waveform point has a marker on off condition associated with it Marker level 3 3V CMOS high positive polarity selected 3 3V CMOS low negative polarity selected Output on these pins occurs whenever the corresponding marker is on in an Arb based waveform see Using Waveform Markers on page 82 Patt Trig In 2 pin 6 A TTL CMOS low to TTL CMOS high or TTL CMOS high to TTL CMOS low edge trigger The input to this connector triggers the internal digital modulation pattern generator to start a single pa
123. oints page 83 2 In the second Arb menu page 87 press Set Markers 3 Highlight the desired waveform segment 4 Select the desired marker number Press Marker 1 2 3 4 5 Set the first sample point in the range in this example 5 Press Set Marker On Range Of Points gt First Mkr Point gt 5 gt Enter 6 Set the last marker point in the range The last marker point value must always be less than or equal to the number of points in the waveform and greater than or equal to the first marker point in this example 25 Press Last Mkr Point gt 25 gt Enter 7 Enter the number of sample points that you want skipped in this example 1 Press Skipped Points gt 1 gt Enter 8 Press Apply To Waveform gt Return This causes the marker to occur on every other point one sample point is skipped within the marker point range as shown at right How to view markers is described on page 88 One application of the skipped point feature is the creation of a clock signal as the EVENT output 92 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Viewing a Marker Pulse When a waveform plays page 77 you can detect a set and enabled marker s pulse at the rear panel event connector Aux I O pin that corresponds to that marker number This example demonstrates how to view a marker pulse generated by a waveform segment that has at
124. on Option UNT Only on page 53 Using Pulse Modulation Option UNU on page 57 I Q Modulation on page 121 Annunciator indicates active AM modulation AM modulation format on A lit LED indicates that any active modulation format can modulate the carrier Agilent N5181A 82A MXG Signal Generators User s Guide 35 Basic Operation Viewing Saving and Recalling Data Viewing Saving and Recalling Data The signal generator enables you to store data as files and view those files in a file catalog From the File Catalog shown in Figure 3 4 you can delete copy or rename a stored file Viewing a Stored File on page 36 Saving and Recalling Data on page 37 See also Working with Instrument State Files on page 38 Selecting Internal or External Media on page 41 Storing Loading and Playing a Waveform Segment on page 70 Figure 3 4 File Softkeys Instrument operating parameters see page 38 Sweep data from the List Mode Values table editor User flatness calibration corrections See page 136 Note Available file types depend on the installed options Waveform files and their associated marker and header information Note If you open the External Media menu without external USB media connected the signal generator displays the message External Media Not Detected See page 41 For details on each key use key help as described on page 23 36 Agilent N5181A 82A MXG Signal G
125. on is Missing from a Recalled Register List sweep information is not stored as part of the instrument state in an instrument state register Only the current list sweep is available to the signal generator You can store list sweep data in the instrument catalog see Saving and Recalling Data on page 37 Amplitude Does Not Change in List or Step Sweep Verify that sweep type is set to amplitude Amptd the amplitude does not change when the sweep type is set to frequency Freq or waveform Agilent N5181A 82A MXG Signal Generators User s Guide 147 Troubleshooting Internal Media Data Storage Internal Media Data Storage Instrument State Saved but the Register is Empty or Contains the Wrong State If the register number you intended to use is empty or contains the wrong instrument state recall register 99 If you selected a register number greater than 99 the signal generator automatically saves the instrument state in register 99 See also Working with Instrument State Files on page 38 External Media Data Storage Instrument Recognizes External Media Connection but Does Not Display Files If the external media works on other instruments or computers it may simply be incompatible with the signal generator use a different memory stick See the signal generator data sheet for information on compatible media Preset The Signal Generator Does Not Respond If the signal generator does not respond to a preset the
126. orm Clipping a Waveform Digitally modulated signals with high power peaks can cause intermodulation distortion resulting in spectral regrowth that can interfere with signals in adjacent frequency bands The clipping function enables you to reduce high power peaks by clipping the I and Q data to a selected percentage of its highest peak thereby reducing spectral regrowth How Power Peaks Develop on page 106 How Peaks Cause Spectral Regrowth on page 108 How Clipping Reduces Peak to Average Power on page 109 Configuring Circular Clipping on page 112 Configuring Rectangular Clipping on page 113 Figure 8 9 Clipping Softkeys Mode gt Dual ARB gt More gt More gt Available only when clipping type I Q For details on each key use key help as described on page 23 106 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Clipping a Waveform How Power Peaks Develop To see how clipping reduces high power peaks it is important to understand how the peaks develop as you construct a signal Multiple Channel Summing I Q waveforms can be the summation of multiple channels as shown in the following figure If a bit in the same state high or low occurs simultaneously in several individual channel waveforms an unusually high power peak positive or negative occurs in the summed waveform Because the high and low states of the bits in ch
127. orrection at the RF Output Press Return gt Flatness Off On The UF annunciator appears in the AMPLITUDE area of the display and the correction data in the array is applied to the RF output Recalling and Applying a User Flatness Correction Array The following example assumes that a user flatness correction array has been created and stored If not perform the Example A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction Values on page 45 1 Preset the signal generator 2 Recall the desired User Flatness Correction file a Press AMPTD gt More gt User Flatness gt Configure Cal Array gt More gt Preset List gt Confirm Preset b Press More gt Load Store c Highlight the desired file d Populate the user flatness correction array with the data contained in the selected file Press Load From Selected File gt Confirm Load From File The user flatness correction array title displays User Flatness Name of File 3 Apply the correction data in the array to the RF output Press Return gt Flatness Off On Agilent N5181A 82A MXG Signal Generators User s Guide 47 Optimizing Performance Using Unleveled Operating Modes Using Unleveled Operating Modes Figure 4 2 Power Search and ALC Off Softkeys ALC Off Mode Turning ALC off deactivates the signal generator s automatic leveling circuitry enabling you to measure the output at a specific point in a test setup and adjust as requir
128. ory Option 006 Only 136 Erase All 136 Erase and Overwrite All 137 Erase and Sanitize All 137 Secure Mode 137 Securing a Nonfunctioning Instrument 138 Using the Secure Display Option 006 Only 139 11 Troubleshooting Display 142 The Display is Too Dark to Read 142 Signal Generator Lock Up 142 RF Output 143 No RF Output 143 Power Supply Shuts Down
129. ot downloaded a waveform segment either refer to the Programming Guide or use one of the factory supplied segments 1 Press Mode gt Dual ARB gt Select Waveform gt Waveform Segments 2 In the Segment On BBG Media column highlight any waveform segment 3 Press Load Store to highlight Store 4 Highlight the waveform segment you want to store 5 Optionally rename the segment If there is already a copy of this segment in the currently selected media and you do not want to overwrite it rename the waveform segment before you store it a Press More gt Rename Segment gt Clear Text b Enter a name for the waveform segment c Press Enter gt More d Highlight the waveform segment that was renamed 6 Press Store Segment to currently selected Media See page 82 For details on each key use key help as described on page 23 Note When a sequence is highlighted this key name changes to Show Waveform Sequence Contents Use the arrow keys or knob to highlight a letter or character Agilent N5181A 82A MXG Signal Generators User s Guide 71 Basic Digital Operation Option 651 652 654 Storing Loading and Playing a Waveform Segment 7 Repeat Step 4 through Step 6 for all segments that you want to store To save all segments from BBG media to the currently selected media press Store All to currently selected Media Loading a Waveform Segment into BBG Media Volatile Memory Waveform segments
130. output on Press RF On Off The RF LED lights and the continuous sweep is available at the RF Output connector Output A signal that continuously sweeps from 500 to 600 MHz and from 20 to 0 dBm with a dwell time of 500 ms at each of six equally spaced points Start frequency 500 MHz Press Freq Start gt 500 gt MHz Stop frequency 600 MHz Press Freq Stop gt 600 gt MHz Amplitude at the beginning of the sweep 20 dBm Press Amptd Start gt 20 gt dBm Amplitude at the end of the sweep 0 dBm Press Amptd Stop gt 0 gt dBm 6 sweep points Press Points gt 6 gt Enter Dwell time at each point 500 milliseconds Press More gt Step Dwell gt 500 gt msec Dwell Time the time that the signal is settled and you can make a measurement before the sweep moves to the next point Point to point time is the sum of the value set for the dwell plus processing time switching time and settling time Lin steps equally spaced over the sweep the output changes linearly Log step spacing increases logarithmically over the sweep the output changes exponentially Step Sweep and List Sweep dwell times are set independently For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 29 Basic Operation Configuring a Swept Output List Sweep List sweep enables you to enter frequencies and amplitudes at unequal intervals in nonlinear a
131. pe determines the behavior of the waveform when it plays see Trigger Type on page 99 Source determines how the signal generator receives the trigger that starts the modulating waveform playing see Trigger Source on page 100 Mode gt Dual ARB gt See page 99 See For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 99 Basic Digital Operation Option 651 652 654 Triggering a Waveform Trigger Type Type defines the trigger mode how the waveform plays when triggered Continuous mode repeats the waveform until you turn the signal off or select a different waveform trigger mode or response Free Run Trigger amp Run Reset amp Run Single mode plays the waveform once Segment Advance mode plays a segment in a sequence only if triggered The trigger source controls segment to segment playing see Example Segment Advance Triggering on page 101 A trigger received during the last segment loops play to the first segment in the sequence Gated mode triggers the waveform at the first active triggering state then repeatedly starts and stops playing the waveform in response to an externally applied gating signal See Example Gated Triggering on page 102 Mode gt Dual ARB gt Trigger Type gt Immediately triggers and plays the waveform triggers received while the waveform is playing are ignored Plays the waveform wh
132. ple Clock gt 50 gt MHz 5 Press Real time Noise Setup and set the following Carrier to Noise Ratio 30 dB Carrier Bandwidth 40 MHz Noise Bandwidth 45 MHz Real time Noise on The signal generator s displayed power level 10 dBm includes the noise power 132 Agilent N5181A 82A MXG Signal Generators User s Guide Adding Real Time Noise to a Signal Option 403 Using Real Time I Q Baseband AWGN Using Real Time I Q Baseband AWGN Figure 9 2 Real Time I Q Baseband AWGN Softkeys Use the following steps to apply 10 MHz bandwidth noise to a 500 MHz 10 dBm carrier 1 Configure the noise a Preset the signal generator b Press Mode gt Real Time I Q Baseband AWGN c Press Bandwidth gt 10 gt MHz 2 Generate the noise Press AWGN Off On until On highlights During generation the AWGN and I Q annunciators activate as shown at right AWGN is now available to modulate the RF carrier 3 Configure the RF output Frequency 500 MHz Amplitude 10 dBm RF output on The carrier with AWGN is now available at the signal generator s RF OUTPUT connector For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 133 10 Working in a Secure Environment Understanding Memory Types on page 134 Removing Data from Memory Option 006 Only on page 136 Using the Sec
133. quency b Set the RF output amplitude c Turn on the RF output The waveform sequence is now available at the signal generator s RF OUTPUT connector Current waveform selection Annunciators display with active waveform ARB On 78 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Saving a Waveform s Settings amp Parameters Saving a Waveform s Settings amp Parameters This section describes how to edit and save a file header When you download only a waveform file I Q data which the signal generator treats as a waveform segment the signal generator automatically generates a file header and a marker file with the same name as the waveform file Initially the file header has no signal generator settings saved to it and the marker file consists of all zeros For a given waveform you can save signal generator settings and parameters in its file header and marker settings in its marker file page 82 when you load a stored waveform file into BBG media the file header and marker file settings automatically apply to the signal generator so that the dual ARB player sets up the same way each time the waveform file plays Figure 8 5 Header Utilities Softkeys When you create a waveform sequence as described on page 75 the signal generator automatically creates a waveform sequence header that takes priority over the individual waveform segment headers During a waveform sequ
134. r Information 79 Viewing amp Editing a Header without Selecting the Waveform 81 Using Waveform Markers 82 Waveform Marker Concepts 83 Accessing Marker Utilities 87 Viewing Waveform Segment Markers 88 Clearing Marker Points from a Waveform Segment 88 Setting Marker Points in a Waveform Segment 89 Viewing a Marker Pulse 92 Using the RF Blanking Marker Function 93 Setting Marker Polarity 94 Controlling Markers in a Waveform Sequence 95 Using the EVENT Output Signal as an Instrument Trigger 97 Triggering a Waveform
135. r the selections and the changes saved to the sequence file The following figure shows a sequence built using one of the factory supplied waveform segments a factory supplied segment has a marker point on the first sample for all four markers In this example marker 1 is enabled for the first segment marker 2 is enable for the second segment and markers 3 and 4 are enabled for the third segment For each segment only the markers enabled for that segment produce a rear panel auxiliary output signal In this example the marker 1 auxiliary signal appears only for the first segment because it is disabled for the remaining segments The marker 2 auxiliary signal appears only for the second segment and the marker 3 and 4 auxiliary signals appear only for the third segment Sequence marker column This entry shows that markers 3 and 4 are enabled for this segment Agilent N5181A 82A MXG Signal Generators User s Guide 97 Basic Digital Operation Option 651 652 654 Using Waveform Markers Using the EVENT Output Signal as an Instrument Trigger One of the uses for the EVENT output signal marker signal is to trigger a measurement instrument You can set up the markers to start the measurement at the beginning of the waveform at any single point in the waveform or on multiple points in the waveform To optimize the use of the EVENT signal for measurements you may also need to adjust the sample rate The location of the sample
136. r to a known state factory or user defined See Presetting the Signal Generator on page 23 See page 42 See page 38 See page 35 See page 26 See page 53 See page 57 Active only on vector models See page 26 See page 27 See page 15 See page 23 See page 67 Reserved for future use Agilent N5181A 82A MXG Signal Generators User s Guide 5 Signal Generator Overview Front Panel Overview 12 RF Output 13 RF On Off and LED This hardkey toggles the operating state of the RF signal present at the RF OUTPUT connector The RF On Off LED lights when RF output is enabled 14 Mod On Off and LED This hardkey enables or disables the modulation of the output carrier signal by an active modulation format This hardkey does not set up or activate a format see Modulating the Carrier Signal on page 34 The MOD ON OFF LED lights when modulation of the output is enabled 15 Page Down In a table editor use this hardkey to display the next page See Example Using a Table Editor on page 25 When text does not fit on one page in the display area use this key in conjunction with the Page Up key page 4 to scroll text 16 I Input vector models only See also I Q Modulation on page 121 17 Q Input vector models only See also I Q Modulation on page 121 Connector Standard Option 1EM Impedance female Type N Rear panel female Type N 50 Damage Levels
137. re in analog form You can use these rear panel I and Q signals to drive a system s transmitter stage test individual analog I and Q components such as an I Q modulator route the I and Q signals into another signal generator The factory default setting routes the internally generated I and Q signals to the I Q modulator and the rear panel I and Q output connectors However to optimize apply calibration factors the rear panel signals you need to select the external I Q output path Select and Play a Waveform 1 Press Mode gt Dual ARB gt Select Waveform 2 Highlight the desired waveform 3 Press Select Waveform gt ARB Off On to On Optimize the Signal Path 1 Connect cables from the rear panel I and Q connectors to either a DUT or another signal generator When you turn the ARB on the signal generator automatically outputs the I and Q signals to the rear panel connectors You can use the rear panel I and Q signals as I and Q inputs to another signal generator The MXG has front panel connectors I Input and Q Input for this purpose 2 Press I Q gt I Q Correction Optimized Path gt Ext I Q Output Agilent N5181A 82A MXG Signal Generators User s Guide 123 Basic Digital Operation Option 651 652 654 I Q Modulation When you optimize a path the path indicator turns green Factory default setting RF Output path optimized Rear panel I Q path optimized 124 Agilent N5181A 82A MXG Signal G
138. rence I Q gain ratio Agilent N5181A 82A MXG Signal Generators User s Guide 127 Basic Digital Operation Option 651 652 654 I Q Calibration I Q Calibration Use the I Q calibration for I and Q signal corrections What aspects of the I and Q signal is corrected depends on whether the signal is internally or externally generated When you perform an I Q calibration that calibration data takes precedence over the factory supplied calibration data The calibration routines improves performance that may degrade over time or due to temperature changes Correction Internal I and Q External I and Q Offset X X Gain Balance X Quadrature Error X X I Q gt I Q Calibration gt Available only when Calibration type User For details on each key use key help as described on page 23 DC optimizes the I Q performance for the current instrument settings and typically completes in several seconds Changing any instrument setting except for I Q adjustments after performing a DC calibration voids the DC calibration and causes the signal generator to revert to the factory supplied calibration data Presetting the instrument or cycling power is equivalent to pressing Revert to Default Cal Setting User provides a quicker calibration when a full calibration is not required You can limit the calibration by specifying the calibration start and stop frequencies When you limit the calibration to less than the instr
139. rs User s Guide 27 Basic Operation Configuring a Swept Output Configuring a Swept Output The signal generator has two methods of sweeping through a set of frequency and amplitude points Step sweep page 28 provides a linear or logarithmic progression from one selected frequency or amplitude or both to another pausing at linearly or logarithmically spaced points steps along the sweep The sweep can progress forward backward or manually List sweep page 29 enables you to enter frequencies and amplitudes at unequal intervals in nonlinear ascending descending or random order List sweep also enables you to copy the current step sweep values include an Arb waveform in a sweep on a vector instrument and save list sweep data in the file catalog page 37 Figure 3 2 Sweep Softkeys Sweep without waiting for a trigger at each point Point Trigger pauses for the dwell time prior to the first sweep Apply a TTL CMOS signal to the Trigger In connector Periodically issue a trigger event to whatever selects it as a source Using timer trigger with single sweep results in a delay prior to the first sweep Trigger on a remote command Down sweeps from stop to start frequency amplitude Up sweeps from start to stop frequency amplitude See page 28 See page 29 The selected sweep type determines the displayed parameter Available when Sweep Type List See page 33 During a frequency sweep the CW
140. rtable with functions such as setting power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter See Also Adding Real Time Noise to a Dual ARB Waveform on page 130 64 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation No BBG Option Installed I Q Modulation I Q Modulation The following factors contribute to the error vector magnitude Differences in amplitude phase and delay between the I and Q channels DC offsets The I Q menu provides adjustments to compensate for some of the differences in the I and Q signals or to add impairments See also Modulating the Carrier Signal on page 34 Figure 7 1 I Q Display and Softkeys The following table shows common uses for the adjustments Table 7 1 I Q Adjustments Uses I Q Adjustment Effect Impairment Offset Carrier Feedthrough dc offset Quadrature Angle EVM error phase skew I Q Images I Q path delay This panel displays the external I Q signal routing This panel displays the current status and settings of the I Q adjustments Grey indicates I Q adjustments are off For details on each key use key help as described on page 23 Offsets the phase of the Q signal relative to the phase of the I signal The quadrature adjustment key is calibrated in units of degrees This adjustment is not calibrated Sets the dc offset
141. s Apply To Waveform gt Return This sets a range of waveform marker points The marker signal starts on sample point 10 and ends on sample point 20 as shown in the following figure 90 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers How to view markers is described on page 88 Agilent N5181A 82A MXG Signal Generators User s Guide 91 Basic Digital Operation Option 651 652 654 Using Waveform Markers Placing a Marker on a Single Point On the First Point 1 In the second Arb menu page 87 press Set Markers 2 Highlight the desired waveform segment 3 Select the desired marker number Press Marker 1 2 3 4 4 Press Set Marker On First Point This sets a marker on the first point in the segment for the marker number selected in Step 3 On Any Point Use the steps described in Placing a Marker Across a Range of Points on page 89 but set both the first and last marker point to the value of the point you want to set For example if you want to set a marker on point 5 set both the first and last value to 5 Placing Repetitively Spaced Markers The following example sets markers across a range of points and specifies the spacing skipped points between each marker You must set the spacing before you apply the marker settings you cannot apply skipped points to a previously set range of points 1 Remove any existing marker p
142. s of Reverse Power on ALC Agilent N5181A 82A MXG Signal Generators User s Guide 145 Troubleshooting RF Output The solution at right shows a similar configuration with the addition of a 10 dB attenuator connected between the RF output of the signal generator and the input of the mixer The signal generator s ALC level increases to 2 dBm and transmits through a 10 dB attenuator to achieve the required 8 dBm amplitude at the mixer input Compared to the original configuration the ALC level is 10 dB higher while the attenuator reduces the LO feedthrough and the signal generator s RF output by 10 dB Using the attenuated configuration the detector is exposed to a 2 dBm desired signal versus the 15 dBm undesired LO feedthrough This 17 dB difference between desired and undesired energy results in a maximum 0 1 dB shift in the signal generator s RF output level Mixer LO ALC Level RF Output 2 dBm RF Level Control Signal Generator Output Control Detector measures 2 dBm ALC level Detector measures 15 dBm reverse power LO Feedthru 5 dBm RF Output 8 dBm LO Level 10 dBm IF Reverse Power Solution 10 dB ATTEN 146 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting Sweep Sweep Cannot Turn Off Sweep Press Sweep gt Sweep gt Off Sweep Appears Stalled The current status of the sweep is indicated as a shaded rectangle in
143. s website 1 Open http www agilent com find mxg 2 Select the desired model number 3 In the options and price list section click price list Agilent N5181A 82A MXG Signal Generators User s Guide 3 Signal Generator Overview Front Panel Overview Front Panel Overview 1 Host USB Use this universal serial bus USB to connect a memory stick for data transfer You can connect or disconnect a USB device without shutting down or restarting the signal generator The instrument also has a rear panel device USB connector see page 11 used to remotely control the instrument 2 Display The LCD screen provides information on the current function Information can include status indicators frequency and amplitude settings and error messages Labels for the softkeys are located on the right hand side of the display See also Front Panel Display on page 7 3 Softkeys A softkey activates the function indicated by the displayed label to the left of the key 4 Numeric Keypad The numeric keypad comprises the 0 through 9 hardkeys a decimal point hardkey a minus sign hardkey and a backspace hardkey See Entering and Editing Numbers and Text on page 24 5 Arrows and Select The Select and arrow hardkeys enable you to select items on the signal generator s display for editing See Entering and Editing Numbers and Text on page 24 Connector Type A USB Protocol 2 0 22 Power Switch and LEDs
144. s within a waveform sequence to enable or disable each segment s markers independently You can enable or disable the markers either at the time of creating the sequence or after the sequence has been created and stored If the sequence has already been stored you must store the sequence again after making any changes Enabling a marker that has no marker points has no effect on the auxiliary outputs To set marker points on a segment see Setting Marker Points in a Waveform Segment on page 89 This example assumes that a waveform sequence exists 1 Ensure that all waveform segments for the sequence reside in BBG media see page 71 2 From the third Arb menu press Waveform Sequences 3 Highlight the desired waveform sequence 4 Press Edit Selected Waveform Sequence gt Enable Disable Markers 5 Toggle the markers a Highlight the first waveform segment b As desired press Toggle Marker 1 Toggle Marker 2 Toggle Marker 3 and Toggle Marker 4 An entry in the Mkr column see figure below indicates that the marker is enabled for that segment no entry in the column means that all markers are disabled for that segment c In turn highlight each of the remaining segments and repeat Step b 6 Press Return gt More gt Name and Store 7 Either rename the sequence using the text entry keys see page 70 or just press Enter to save the sequence with the existing name The markers are enabled or disabled pe
145. scending descending or random order List sweep also enables you to copy the current step sweep values include a waveform in a sweep on a vector instrument and save list sweep data in the file catalog page 37 Dwell time is editable at each point Figure 3 3 List Sweep Configuration Softkeys and Display see page 30 The selected sweep determines which dwell time the signal generator uses Step Sweep dwell time is the same at each point List Sweep dwell time can be different at each point Dwell Time the time that the signal is settled and you can make a measurement before the sweep moves to the next point Point to Point Time the sum of the value set for the dwell plus processing time switching time and settling time Each line defines the corresponding point in the sweep For example line 1 defines point 1 See page 28 Available only on vector models and only when Sweep Type List Displays the selected sweep type parameters see page 30 Vector models only See page 33 For details on each key use key help as described on page 23 Available only when waveform entry is selected 30 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Operation Configuring a Swept Output Example Configuring a List Sweep Using Step Sweep Data 1 Set up the desired step sweep but do not turn the sweep on This example uses the step sweep configured on page 28 2 In the SWEEP menu change the sweep
146. ser s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Sample range begins on first point of signal Negative range set between signal and off time Example of Incorrect Use Waveform 1022 points Marker range 110 1022 Marker polarity Negative This figure shows that a negative polarity marker goes low during the marker on points the marker signal goes high during the off points The ALC samples the waveform during the off marker points Marker On Marker On Sampling both on and off time sets the modulator circuitry incorrectly for higher signal levels Note the increased amplitude at the beginning of the pulse Marker Off Marker On Marker Marker Off On Agilent N5181A 82A MXG Signal Generators User s Guide 87 Basic Digital Operation Option 651 652 654 Using Waveform Markers Accessing Marker Utilities Mode gt Dual ARB gt More gt Note This is the second Arb menu The display below shows the I and Q components of the waveform and the marker points set in a factory supplied segment First sample point shown on display These softkeys change the range of waveform sample points shown on the marker display Each press of the softkey changes the sample range by approximately a factor of two Marker points on first sample point For details on each key use key help as described on page 23 The settings in these menus can be stored to the file header se
147. set to RF Output see page 122 Agilent N5181A 82A MXG Signal Generators User s Guide 125 Basic Digital Operation Option 651 652 654 I Q Adjustments I Q Adjustments Use the I Q Adjustments to compensate for or add impairments to the I Q signal I Q gt I Q Adjustments gt Available only when a waveform is playing Available only with Option 1EL Adjusts the I signal amplitude relative to the Q signal amplitude Use this as an internal impairment or to compensate for differences in signal path loss that occur due to path irregularities in the external I and Q output cabling Offsets the phase of the Q signal relative to the phase of the I signal The baseband quadrature adjustment key is calibrated in units of degrees The external input quadrature adjustment is not calibrated The function provided by this key is not the same as the function provided by the I Q Skew key Skew is typically used either to create impairments or to reduce error vectors on large bandwidth signals Provides a relative time delay correction between the I and Q signals The different signal paths traveled by the I and Q signals result in time delay differences that show up as an EVM error in large bandwidth modulated signals Adding an equal and opposite time delay skew in the I Q signals during baseband generation eliminates the time delay error correcting for any delays in signals that are generated in the internal baseband ge
148. softkey 16 urls 2 18 21 151 USB connecting media 41 definition 154 device connector 11 host connector 3 troubleshooting 147 Use Current Directory As Default Path softkey 41 user documentation content ix files backup and restore 35 flatness correction 44 preset 23 preset troubleshooting 147 User softkeys Current Directory As Default Path 36 Flatness 26 35 Flatness Correction 44 Span 47 User 17 Utility hardkey 15 V vector operation 67 View Next Error Page softkey 42 View Previous Error Page softkey 42 volatile memory 68 71 Volatile Segments softkey 35 78 VXI 11 enabling 20 VXT 11 SCPI softkey 20 W Waveform softkeys Licenses 21 Runtime Scaling 115 Segments 70 Sequences 74 95 Utilities 115 Waveform 27 29 waveforms clipping 105 file headers 78 from digital baseband waveform 116 in a sweep 31 license 21 markers 82 83 memory 135 overview 68 saving instrument state 38 scaling 114 segment softkeys 70 sequence 74 storing loading amp playing 70 triggering 98 web server 20 Web Server softkey 20 WINIT annunciator 8 Y yellow LED 6 Z Zoom softkeys 87 164 Agilent N5181A 82A MXG Signal Generators User s Guide Index
149. softkeys used in the following steps b Set the ARB sample clock to 5 MHz Press ARB Sample Clock gt 5 gt MHz c Set waveform runtime scaling to 60 Press Waveform Runtime Scaling gt 60 gt d Return to the Header Utilities menu Press Return gt More gt More gt Header Utilities As shown in the following figure the Current Inst Settings column now reflects the changes to the current signal generator setup but the saved header values have not changed e Save the current settings to the file header Press the Save Setup To Header softkey The settings from the Current Inst Settings column now appear in the Saved Header Settings column This saves the new current instrument settings to the file header If you change any of the signal generator settings listed in the file header after you select the waveform file the changed setting s appear in the file header s Current Inst Settings column and are used instead of the saved header settings To reapply the saved header settings reselect the waveform for playback Values differ between the two columns Agilent N5181A 82A MXG Signal Generators User s Guide 81 Basic Digital Operation Option 651 652 654 Saving a Waveform s Settings amp Parameters Viewing amp Editing a Header without Selecting the Waveform As described on page 79 you can view and edit a waveform s header information after you select the waveform you can also edit waveform he
150. splay this softkey highlight a waveform sequence Agilent N5181A 82A MXG Signal Generators User s Guide 75 Basic Digital Operation Option 651 652 654 Waveform Sequences Creating a Sequence A waveform sequence can contain up to 1 024 segments and have both segments and other sequences nested sequences The signal generator lets you set the number of times the segments and nested sequences repeat during play back But there is a difference between repeating a segment versus repeating a nested sequence Each segment can repeat up to 65 535 times but no matter how many times a segment repeats it counts as a single segment However each repetition of a nested sequence counts as additional segments The maximum number of times that a nested sequence can repeat is based on the number of segments in the nested sequence and the remaining number of allowed segments 1 024 For example with a sequence that contains 24 segments and one nested sequence with 4 segments the nested sequence is limited to 250 repetitions 24 4 250 1 024 maximum number of segments per sequence Even though there is a limiting factor on the maximum number of times that a nested sequence can repeat each segment within the nested sequence can repeat up to 65 535 times Example Use the following procedure to create and store a waveform sequence using one repetition each of two different segments Assumption The waveform segments are in BBG media volat
151. st of the waveform In many cases data that might otherwise be lost in the clipping process is retained because of the error correction inherent in the coded systems If you apply excessive clipping however lost data cannot be recovered Experiment with clipping settings to find a percentage that reduces spectral regrowth while retaining needed data Figure 8 10 Circular Clipping 110 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Clipping a Waveform Figure 8 11 Rectangular Clipping Agilent N5181A 82A MXG Signal Generators User s Guide 111 Basic Digital Operation Option 651 652 654 Clipping a Waveform Figure 8 12 Reduction of Peak to Average Power 112 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Clipping a Waveform Configuring Circular Clipping Use this example to configure circular clipping and observe its affect on the peak to average power ratio of a waveform Circular clipping clips the composite I Q data I and Q data are clipped equally For more information about circular clipping refer to How Clipping Reduces Peak to Average Power on page 109 CAUTION Clipping is non reversible and cumulative Save a copy of the waveform file before you apply clipping Copy a Waveform File 1 Display the signal generator s files Press File gt Catalog Type gt More gt Volatile Segments 2 Hi
152. stores persistent settings those unaffected by a power cycle preset or recall Available only when 8648 is either the selected preset language or the selected GPIB remote language see page 19 Note To define a user preset set the instrument up as desired and press User Preset gt Save User Preset Makes the increment value of the current function the active entry Utility gt Instrument Adjustments gt The increment value and the step knob ratio determine how much each turn of the knob changes the active function value For example if the increment value of the active function is 10 dB and the step knob ratio is 50 to 1 each turn of the knob changes the active function by 0 2 dB 1 50th of 10 dB To change the amount for each turn of the knob modify the increment value the step knob ratio or both For details on each key use key help as described on page 23 18 Agilent N5181A 82A MXG Signal Generators User s Guide Setting Preferences amp Enabling Options Upgrading Firmware Setting Time and Date The signal generator s firmware tracks the time and date and uses the latest date and time that has been set as its time date reference point Setting the Time or Date Forward If you set the time or date forward be aware that you are using up any installed time based licenses and that you are resetting the signal generator s time date reference point When you set a new time or date that is later than
153. sweep has been initiated and the signal generator is waiting for the sweep trigger event ATTNHOLD The attenuator hold function is on When this function is on the attenuator is held at its current setting DETHTR The ALC detector heater is not up to temperature To meet ALC specifications the heater must be at temperature AWGN Real Time I Q Baseband additive white Gaussian noise is on 5 Error Message Area 6 Text Area 7 Softkey Label Area 4 Amplitude Area 3 Annunciators 2 Frequency Area 1 Active Function Area Scroll Bar If there is more text than can be displayed on one screen a scroll bar appears here Use the Page Up and Page Down keys to scroll through the text 8 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Front Panel Display 4 Amplitude Area This area displays the current output power level setting 5 Error Message Area This area displays abbreviated error messages If multiple messages occur only the most recent message remains displayed See Reading Error Messages on page 42 6 Text Area This area displays signal generator status information such as the modulation status and other information such as sweep lists and file catalogs This area also enables you to perform functions such as managing information entering information and displaying or deleting files 7 Softkey Label Area This area displays labels that define the function of t
154. t Panel Display on page 7 Rear Panel Overview on page 9 2 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Signal Generator Features Signal Generator Features N5181A analog models 250 kHz to 1 3 or 6 GHz N5182A vector models 250 kHz to 3 or 6 GHz electronic attenuator step amp list sweep of frequency power or frequency and power vector models can include waveforms in list sweep user flatness correction automatic leveling control ALC power calibration 10 MHz reference oscillator with external output flexible reference input 1 50 MHz Option 1ER GPIB USB 2 0 and 100Base T LAN interfaces analog modulation AM FM and M Option UNT external AM FM and M inputs Option UNT pulse modulation Option UNU SCPI and IVI COM driver 8648 ESG code compatible LXI Class C compliant external analog I Q inputs vector models analog differential I Q outputs vector models Option 1EL arbitrary I Q waveform playback up to 125 MSa s vector models Option 654 with Signal Studio Software vector models can generate 802 11 WLAN W CDMA cdma2000 1xEV DO GSM EDGE and more For more details on hardware firmware software and documentation features and options refer to the data sheet shipped with the signal generator and available from the Agilent Technologie
155. t when the marker signal goes low This example is a continuation of the previous example Viewing a Marker Pulse 1 Using the factory supplied segment SINE_TEST_WFM set Marker 1 across points 1 180 page 89 2 From the Marker Routing softkey menu assign RF Blanking to Marker 1 In the second Arb menu page 87 press Marker Routing gt Pulse RF Blank gt Marker 1 Marker Polarity Positive When marker polarity is positive the default setting the RF output is blanked during the off marker points 200 180 Point 1 Marker Segment RF Signal RF Signal 200 180 Point 1 Marker Segment Marker Polarity Negative When marker polarity is negative the RF output is blanked during the on marker points 3 3V 0V 3 3V 0V RF Signal RF Signal 94 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Using Waveform Markers Setting Marker Polarity Setting a negative marker polarity inverts the marker signal 1 In second Arb menu page 87 press Marker Polarity 2 For each marker set the marker polarity as desired The default marker polarity is positive Each marker polarity is set independently See also Saving Marker Polarity and Routing Settings on page 83 As shown on page 93 Positive Polarity On marker points are high 3 3V Negative Polarity On marker points are low 0V RF blanking always
156. ternal Media 41 Reading Error Messages 42 Error Message Format 42 4 Optimizing Performance Using User Flatness Correction 44 Basic Procedure 44 Example A 500 MHz to 1 GHz Flatness Correction Array with 10 Correction Values 45 Recalling and Applying a User Flatness Correction Array 46 Using Unleveled Operating Modes 47 ALC Off Mode 47 Power Search Mode 48 Using an Output Offset Reference or Multiplier 49 Setting an Output Offset 49 Setting an Output Reference 50
157. the peak to average power ratio Agilent N5181A 82A MXG Signal Generators User s Guide 109 Basic Digital Operation Option 651 652 654 Clipping a Waveform How Clipping Reduces Peak to Average Power You can reduce peak to average power and consequently spectral regrowth by clipping the waveform Clipping limits waveform power peaks by clipping the I and Q data to a selected percentage of its highest peak The Signal Generator provides two methods of clipping Circular clipping is applied to the composite I Q data I and Q data are equally clipped As shown in Figure 8 10 the clipping level is constant for all phases of the vector and appears as a circle in the vector representation Rectangular clipping is independently applied the I and Q data As shown in Figure 8 11 on page 110 the clipping level is different for I and Q and appears as a rectangle in the vector representation In both circular and rectangular clipping the objective is to clip the waveform to a level that reduces spectral regrowth but does not compromise the integrity of the signal The two complementary cumulative distribution plots in Figure 8 12 on page 111 show the reduction in peak to average power that occurs after applying circular clipping to a waveform The lower the clipping value the lower the peak power that is passed the more the signal is clipped The peaks can often be clipped without substantially interfering with the re
158. the signal generator s current reference point that date becomes the new reference point If you then set the date back you run the risk described in the next section Setting the Time or Date Backward When you set the time back the signal generator notes that the time has moved back from the reference point the latest date that has been set If you set the time back more than approximately 25 hours you disable the signal generator s ability to use time based licenses even if there is no license installed at the time that you set the time back In this case you can reenable the signal generator s ability to use time based licenses by returning the date to within 25 hours prior to the the reference point or to anytime after the reference point If you find you must set the date backward more than approximately 25 hours when for example the time is mistakenly set ahead and you wish to use time based licenses you must contact Agilent Technologies for assistance see page 151 Upgrading Firmware For information on new firmware releases go to http www agilent com find upgradeassistant Changing the time or date can adversely affect the signal generator s ability to use time based licenses even if a time based license is not installed when you change the time or date Utility gt Instrument Adjustments gt CAUTION Original time date reference point Time New time date reference point Point at which t
159. ts 2 Reset the output power to the desired level See also Setting an Output Reference on page 50 If you are using the signal generator with an external mixer see page 144 If you are using the signal generator with a spectrum analyzer see page 144 If pulse modulation is on turn off the ALC and check that pulse width is within specifications Distortion If you edit and resave a segment in a waveform sequence the sequence does not automatically update the RMS value stored in it s header This can cause distortion on the output signal Display the sequence header information and recalculate the RMS value see page 78 144 Agilent N5181A 82A MXG Signal Generators User s Guide Troubleshooting RF Output Signal Loss While Working with a Spectrum Analyzer The effects of reverse power can cause problems with the RF output when you use the signal generator with a spectrum analyzer that does not have preselection Use an unleveled operating mode described on page 47 A spectrum analyzer can have as much as 5 dBm LO feedthrough at its RF input port at some frequencies If the frequency difference between the LO feedthrough and the RF carrier is less than the ALC bandwidth the LO s reverse power can amplitude modulate the signal generator s RF output The rate of the undesired AM equals the difference in frequency between the spectrum analyzer s LO feedthrough and the signal generator s RF carr
160. ts All table editors with original factory values ensuring that user data and configurations are not accessible or viewable Does Not Sanitize memory Time to Erase typically lt 1 minute depending on the number of files To Start Press File gt More gt Security gt Erase All gt Confirm Erase NOTE This is not File gt Delete All Files which deletes all user files but does not reset table editors page 137 Below See Secure Mode on page 137 See page 36 For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 137 Working in a Secure Environment Removing Data from Memory Option 006 Only Erase and Overwrite All This performs the same actions as Erase All plus it clears and overwrites the various memory types in accordance with Department of Defense DoD standards as follows CPU Flash Overwrites all addressable locations with random characters and then erases the flash blocks This accomplishes the same purpose as a chip erase System files are restored after erase To Start Press File gt More gt Security gt Erase and Overwrite All gt Confirm Erase Erase and Sanitize All This performs the same actions as Erase and Overwrite All and then adds more overwriting actions After executing this function you must manually perform the additional steps described below for the sanitization to comply with Department of Defense DoD sta
161. ttern output or to stop and re synchronize a pattern that is being continuously output To synchronize the trigger with the data bit clock the trigger edge is latched then sampled during the falling edge of the internal data bit clock This is an external trigger for all ARB waveform generator triggers Minimum pulse width 100 ns Damage levels gt 5 5 and lt 0 5V Sample Rate Clock Out pin 5 This output is used with an internal baseband generator This pin relays a CMOS bit clock signal for synchronizing serial data Damage levels gt 5 5 and lt 0 5V 14 Agilent N5181A 82A MXG Signal Generators User s Guide Signal Generator Overview Rear Panel Overview Agilent N5181A 82A MXG Signal Generators User s Guide 15 2 Setting Preferences amp Enabling Options The Utility menu provides access to both user and remote operation preferences and to the menus in which you can enable instrument options page 16 Front Panel Knob Resolution on page 17 page 17 Enabling an Option on page 21 Configuring the GPIB Interface on page 19 Configuring the LAN Interface on page 20 Enabling LAN Services Browser Sockets and VXI 11 on page 20 User Preferences Remote Operation Setting Time and Date on page 18 Upgrading Firmware on page 18 16 Agilent N5181A 82A MXG Signal Generators User s Guide Setting Preferences amp Enabling Options User Preferences User Preferences From the Utility menu you
162. ulated carrier with 20 MHz baseband frequency offset Modulated RF signal LO carrier feedthrough Spectrum analyzer set to a span of 100 MHz 74 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 Waveform Sequences Waveform Sequences Figure 8 4 Waveform Sequence Softkeys A waveform sequence is a file that contains pointers to one or more waveform segments or other waveform sequences or both This lets the signal generator play multiple waveform segments or other sequences or both thereby eliminating the need to stop waveform playback just to select another waveform The segments that a waveform sequence points to are not automatically stored when you store the sequence you must also store the individual segments or they are lost when you turn off or reboot the signal generator If the segments are located in internal external media you must load them into BBG media prior to selecting a waveform sequence If you attempt to play a sequence without the segments loaded into BBG media the signal generator reports ERROR 629 File format invalid If this happens and the segments are not stored in internal external media you must recreate the segments using the same file names that the sequence points to before you can play the sequence For details on each key use key help as described on page 23 Mode gt Dual ARB gt Sequence name Sequence contents see page 95 To di
163. ument s full frequency range the factory supplied calibration data is used for the rest of the range Information is retained through a preset or power cycle Full takes 5 minutes executing measurements over the instrument s entire frequency range Information is retained through a preset or power cycle Deletes any user generated calibration data and restores the factory supplied calibration data 128 Agilent N5181A 82A MXG Signal Generators User s Guide Basic Digital Operation Option 651 652 654 I Q Calibration Agilent N5181A 82A MXG Signal Generators User s Guide 129 9 Adding Real Time Noise to a Signal Option 403 Before using this information you should be familiar with the basic operation of the signal generator If you are not comfortable with functions such as setting the power level and frequency refer to Chapter 3 Basic Operation on page 23 and familiarize yourself with the information in that chapter This chapter contains examples of using the additive white gaussian noise AWGN waveform generator which is available only in vector signal generators with Option 403 Adding Real Time Noise to a Dual ARB Waveform on page 130 Using Real Time I Q Baseband AWGN on page 132 130 Agilent N5181A 82A MXG Signal Generators User s Guide Adding Real Time Noise to a Signal Option 403 Adding Real Time Noise to a Dual ARB Waveform Adding Real Time Noise to a Dual ARB
164. ure Display Option 006 Only on page 139 134 Agilent N5181A 82A MXG Signal Generators User s Guide Working in a Secure Environment Understanding Memory Types Understanding Memory Types The signal generator has several memory types and each is used to store a specific type of data Before removing sensitive data you should to understand how each memory type is used The following tables describe each memory type used in the base instrument and optional baseband generator Table 10 1 Base Instrument Memory Memory Type and Size Writable During Normal Operation Data Retained When Powered Off Purpose Contents Data Input Method Location in Instrument and Remarks Main Memory RAM 32 MB Yes No firmware operating memory no user data operating system CPU board Main Memory Flash 8 MB Yes Yes factory calibration configuration data auser file system which includes flatness calibration instrument states and sweep lists firmware upgrades and user saved dataa CPU board same chip as firmware memory but managed separately Because this memory chip contains 8 MB of user data described here and 8 MB of firmware memory a full chip erase is not desirable User data areas are selectively and completely sanitized when you perform the Erase and Sanitize function Firmware Memory Flash 8 MB No Yes main firmware image factory installed or firmware upgrade CPU board same ch
165. ure Environment Using the Secure Display Option 006 Only Using the Secure Display Option 006 Only This function prevents unauthorized personnel from reading the instrument display and tampering with the current configuration through the front panel The display blanks except for the message shown in the following figure and the front panel keys are disabled To re enable the display and front panel keys cycle the power Figure 10 1 Secure Display Softkeys For details on each key use key help as described on page 23 140 Agilent N5181A 82A MXG Signal Generators User s Guide Working in a Secure Environment Using the Secure Display Option 006 Only Agilent N5181A 82A MXG Signal Generators User s Guide 141 11 Troubleshooting Display on page 142 Signal Generator Lock Up on page 142 RF Output on page 143 No RF Output Power Supply Shuts Down No Modulation at the RF Output RF Output Power too Low Distortion Signal Loss While Working with a Spectrum Analyzer Signal Loss While Working with a Mixer on page 144 Sweep on page 146 Cannot Turn Off Sweep Sweep Appears Stalled Incorrect List Sweep Dwell Time List Sweep Information is Missing from a Recalled Register Amplitude Does Not Change in List or Step Sweep on page 146 Internal Media Data Storage on page 147 Instrument State Saved but the Register
166. ve function page 35 to store this value as part of the signal generator setup When you Recall a setup stored with the Save function the baseband frequency offset value becomes the current instrument setting value disregarding the stored file header value See page 130 See page 114 Frequency offset setting The settings in this menu can be stored to the file header see page 78 For details on each key use key help as described on page 23 Agilent N5181A 82A MXG Signal Generators User s Guide 73 Basic Digital Operation Option 651 652 654 Setting the Baseband Frequency Offset Use the following steps to offset the carrier from LO carrier feedthrough This example uses the factory supplied waveform SINE_TEST_WFM To view the output for this example connect the RF OUTPUT of the signal generator to the input of a spectrum analyzer 1 Select and play the waveform a Press Mode gt Dual ARB gt Select Waveform b In the Segment On BBG Media column select SINE_TEST_WFM c Press Select Waveform 2 Generate the waveform Press ARB Off On to On 3 Configure the carrier signal a Set the carrier signal to 1 GHz b Set the amplitude to 0 dBm c Turn on the RF OUTPUT 4 Press ARB Setup gt Baseband Frequency Offset gt 20 MHz The modulated RF signal is now offset from the carrier frequency by 20 MHz as shown in the following figures Modulated carrier with 0 Hz baseband frequency offset Mod
167. wept Output 27 Step Sweep 28 List Sweep 29 Example Using a Single Sweep 32 Contents Agilent N5181A 82A MXG Signal Generators User s Guide v Example Manual Control of Sweep 33 Routing Signals 33 Modulating the Carrier Signal 34 Example 34 Viewing Saving and Recalling Data 35 Viewing a Stored File 36 Saving and Recalling Data 37 Working with Instrument State Files 38 Selecting Internal or Ex
168. witch selects the standby mode or the power on mode In the standby position the yellow LED lights and all signal generator functions deactivate The signal generator remains connected to the line power and some power is consumed by some internal circuits In the on position the green LED lights and the signal generator functions activate Agilent N5181A 82A MXG Signal Generators User s Guide 7 Signal Generator Overview Front Panel Display Front Panel Display 1 Active Function Area This area displays the currently active function For example if frequency is the active function the current frequency setting appears If the currently active function has an increment value associated with it that value also appears 2 Frequency Area This area displays the current frequency setting 3 Annunciators Annunciators show the status of some of the signal generator functions and indicate error conditions An annunciator position may be used by more than one annunciator in this case only one of the functions sharing a given position can be active at a given time This annunciator appears when M Phase modulation is on If you turn frequency modulation on the FM annunciator replaces M ARB The ARB generator is on ALC OFF The ALC circuit is disabled The UNLEVEL annunciator appears in the same position if the ALC is enabled and is unable to maintain the output level AM Amplitude modulation is on ARMED A
169. y 100 Delay Time 100 Ext 27 I Q Output 121 122 123 Pulse 58 Source 100 external I and Q signals 124 media 41 147 modulation source 55 trigger source 102 104 triggering 104 External Media Not Detected message 41 External softkeys External 121 Input 125 Input I Offset 64 Input Q Offset 64 Media File Manager 35 Output 125 F factory defaults restoring 17 20 127 features 2 feedthrough 64 file catalog See data storage File hardkey 35 40 file headers creating 78 editing 79 example 79 viewing a different file 81 files See data filter interpolator 116 158 Agilent N5181A 82A MXG Signal Generators User s Guide Index firmware memory 134 upgrading 18 firmware upgrading 151 First Mkr Point softkey 87 First Sample Point softkey 87 flash memory 134 flatness correction See user flatness correction Flatness softkey 44 FM annunciator 8 connector 10 dc offset removing 55 external source 55 hardkey 53 softkeys 53 Free Run softkey 27 99 Free Run softkey 58 FREQ hardkey 26 Freq softkeys 26 29 44 frequency display area 7 hardkey 5 6 26 modulation 53 multiplier 51 offset 49 offset baseband 72 offset setting 72 reference 50 setting 26 softkeys 26 26 29 front panel disabling keys 139 display 7 I Q inputs using 65 knob resolution 17 overview 3 tests 149 front panel memory 135 FTP server 20 FTP Server softkey 20 fund
170. y 99 segment advance triggering 99 segments advance triggering 101 file headers 78 loading 71 softkeys 70 storing loading amp playing 70 Select hardkey 24 Select softkeys Color Palette 16 Different Header 78 81 Header 78 Reg 38 Seq 38 Waveform 29 self test 149 Sequence softkey 35 78 sequences editing 76 file headers 78 marker control 95 playing 77 waveform 74 serial data synchronizing 13 162 Agilent N5181A 82A MXG Signal Generators User s Guide Index server enabling 20 service Agilent offices 151 guide content ix request annunciator 8 Set Marker softkeys 87 settings persistent 153 Show softkeys Alpha Table 24 Waveform Sequence 74 Waveform Sequence Contents 74 95 Signal Studio 2 signal studio licenses 21 Single softkey 99 Single Sweep softkey 27 skew I Q 125 Sockets SCPI softkey 20 sockets enabling 20 softkeys definition of 154 help on 23 label area 8 location 3 See also specific key source settled signal 33 Source Settled softkey 33 58 Span softkey 47 Span Type softkey 47 spectral regrowth 108 spectrum analyzer troubleshooting signal loss 144 Square softkey 58 standby yellow LED 6 State softkey 35 states persistent 153 step array user flatness 45 See also user flatness correction Step Dwell softkey 28 Step Spacing softkey 28 step sweep spacing 28 troubleshooting 146 using 28 Step Knob Ratio softkey 17 Storag
171. y of the Agilent products to which it pertains Should Agilent have a written contract with the User and should any of the contract terms conflict with these terms the contract terms shall control Contents Agilent N5181A 82A MXG Signal Generators User s Guide iii 1 Signal Generator Overview Signal Generator Features 2 Front Panel Overview 3 1 Host USB 3 2 Display 3 3 Softkeys 3 4 Numeric Keypad 3 5 Arrows and Select 3 6 Page Up 4 7 MENUS 4 8 Trigger

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