Fast Remote Control for R&S SMIQ Vector
Contents
1. RN NI Products SMIQ Fast Remote Control for R amp S SMIQ Vector Signal Generators Application Note Short setting times are among the most important criteria when it comes to choosing the right signal generator especially in production With its extremely short setting times for frequency lt 3 ms and level lt 2 5 ms the R amp S SMIQ Vector Signal Generator family easily meets the requirement In addition SMIQ provides two special modes where setting times can be further reduced Fast Restore mode and List Mode This Application Note decribes both modes and gives some application examples amp ROHDE amp SCHWARZ Subject to change Dr Ren Desquiotz 08 2002 1GP55_0E Fast remote control of SMIQ Contents Mh OVEIV OW iscsi tats NEAT E E EI E E A E O EE 2 2 SMIQ Fast Restore ModE scini ien e na aea cies ea aE baad SaN EEN E NRE SNE EEE 2 Working Principle cirerssniiipinei nnen aiarad iada ENA EE eA Aa ia 2 Operation aeae eeraa a Eaa E a eaaa e aaae a ane 3 Application CxA MPlOS is ciccccseccenestaccsceanas onchseapnecy desu vecvsnses duneitedes dncteney raroa K aa Aena laasia 5 S SMIQ LISt MOGC PA EE E A E E E A 9 Working principle asepen a a a e a E A R 9 OpETANON iieii assnnosiel iarann rii ii aapa iai Aaea EN EE a Aa CENE EEA SEA A EOE S 9 Application example Sisihin a e Ea e e aR Eaa a E Dar a A AEN OaS 12 A RReIErenCeS innsir oe niran a ea EE N N EET E eE E a a E aaa E pi iei 15 5 Ordening infOn2. Vector Signal Generator SMIQ Operating Manual PD 1125 5610 12 Rohde amp Schwarz 2002 2 WCDMA Signal Generator Solutions by Rohde amp Schwarz Application Note 1GP39 Rohde amp Schwarz 2000 3 3GPP Base Station Tests with Vector Signal Generator SMIQ Application Note 1GP41 Rohde amp Schwarz 2001 4 Level Accuracy and Electronic Level Settings of SMIQ Application Note 1GP42 Rohde amp Schwarz 2001 5 Ordering information Vector Signal Generator SMIQ02B 300 kHz to 2 2 GHz 1125 5555 02 SMIQ03B 300 kHz to 3 3 GHz 1125 5555 03 SMIQ04B 300 kHz to 4 4 GHz 1125 5555 04 SMIQ06B 300 kHz to 6 4 GHz 1125 5555 06 SMIQO3HD 300 kHz to 3 3 GHz 1125 5555 33 SMIQO6ATE 300 kHz to 6 4 GHz 1125 5555 26 Options SMIQB11 Data Generator 1085 4502 04 SMIQB12 Memory Extension 1085 2800 04 SMIQB14 Fading Simulator 1085 4002 02 SMIQB15 Second Fading Simulator for two channel or 12 path fading 1085 4402 02 SMIQB17 Noise Generator and Distortion Simulator 1104 9000 02 SMIQB20 Modulation Coder 1125 5190 02 SMIQB21 BER Measurement 1125 5490 02 SMIQB42 Digital Standard IS 95 1104 7936 02 SMIQB45 Digital Standard WCDMA 3GPP 1104 8232 02 SMIQB47 Low ACP for CDMA and WCDMA 1125 5090 02 SMIQB48 Extended Functions for WCDMA 3GPP 1105 0587 02 SMIQB49 Extended Fading Functions for WCDMA 3GPP 1105 1083 02 SMIQB51 Digital Standard GPS 1105 1831 02 SMIQB60 Arbitrary Waveform Generator incl WinlQSIM 1136 4390 02 SMIQ K8 TETRA T1 Simulator
3. 1136 4290 02 WinlQSIM Options SMIQK11 Digital Standard IS 95 option SMIQB60 required 1105 0287 02 SMIQK12 Digital Standard cdma2000 option SMIQB60 required 1105 0435 02 SMIQK13 Digital Standard WCDMA Mode TDD 3GPP 1105 1231 02 option SMIQB60 required SMIQK14 Digital Standard TD SCDMA option SMIQB60 required 1105 1383 02 SMIQK15 OFDM Signal Generation option SMIQB60 required 1105 1531 02 SMIQK16 Digital Standard IEEE 802 11b option SMIQB60 required 1154 7700 02 SMIQK17 Digital Standard 1xEV DO option SMIQB60 required 1154 7800 02 SMIQK18 Digital Standard IEEE 802 11a option SMIQB60 required 1154 7952 02 ROHDE amp SCHWARZ ROHDE amp SCHWARZ GmbH amp Co KG MihldorfstraRe 15 D 81671 M nchen P O B 80 14 69 D 81614 M nchen Telephone 49 89 4129 0 Fax 49 89 4129 13777 Internet http Awww rohde schwarz com This application note and the supplied programs may only be used subject to the conditions of use set forth in the download area of the Rohde amp Schwarz website 1GP55_0E 15 Rohde amp Schwarz
4. an EDGE burst in timeslot 0 all other time slots off After transmission of the burst hop to a different frequency For simplicity we use only two frequencies here and only one RF level 10 dBm Solution Set the GSM frame in Digital Standard GSM EDGE Activate a hop trigger at the end of timeslot 0 Then run the list mode in HOP mode Note Options SMIQB11 and SMIQB20 are required for this example Rohde amp Schwarz Fast remote control of SMIQ Command Remarks ARSTSECES Sets the instrument to a defined state Note that RST switches off the RF output SOUR FREQ 890 2K6 Sets the carrier frequency to 890 2 MHz SOUR POW 10dBm Sets the RF level to 10 dBm SOUR GSM SLOTO TYPE EDGE Timeslot O is set to an EDGE burst Note that the RST value for timeslots 1 to 7 is off so only timeslot 0 has to be configured here SOUR GSM SLOTO HOPP TRIG ON Activates the HOP trigger at the end of timeslot 0 SOUR GSM SEQ AAUT Sets GSM to ARMED AUTO mode i e the GSM signal is not output until a trigger event is received The baseband generator is held at the first symbol of the frame This will produce a CW signal at the RF output as soon as the RF is switched on Note If your application requires that there is no signal present before the list mode is started you should activate timeslot 1 instead of timeslot 0 in the GSM frame If you need the ti
5. below IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE AUTO tTRIG LIST SOUR EXT EXT STEP Step by step run by means of the external trigger signal TRIGGER input on the rear panel see below Each trigger event triggers a single step IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE STEP TRIG LIST SOUR EXT 1GP55_0E 10 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ HOP Step by step run by means of the internal trigger signal of the data generator see also Section Internal Modulation Data and Control Signals from Lists and Section Menu DIGITAL STANDARD GSM Each trigger event triggers a single step IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE STEP TRIG LIST SOUR HOP OFF Operating mode LIST is switched off IEC IEEE bus command SOUR FREQ MODE CW Note The minimum step time of 1 ms must not be violated in modes EXT STEP and HOP either With fading switched on the minimum step time is increased to 3 ms in case of Lognormal fading it is increased to 50 ms TRIGGER input and BLANK output are available at the rear of the instrument for synchronization with other instruments TRIGGER An external signal at this input triggers the LIST mode in operating modes EXT SINGLE and EXT STEP The polarity of the active trigger edge can be set in the UTILITIES AUX I O EXT TRIG SL
6. minimum step time is 10 ms Solution Set the attenuator mode to ELECTRONIC to get 90 dB noninterrupting level setting range The levels are stored in a list then the list mode is run in SINGLE mode with 3 ms dwell time The commands for the entire procedure are as follows Command Remarks RST CLS Sets the instrument to a defined state Note that RST switches off the RF output SOUR FREQ 2E9 Sets the carrier frequency to 2 GHz SOUR POW 0 Sets the RF level to 0 dBm To obtain a level setting range from 90 dBm to 0 dBm in attenuator mode ELECTRONIC this command has to be sent before switching to ELECTRONIC mode OUTP AMOD ELEC Sets attenuator mode ELECTRONIC This leads to uninterrupted level settings in a range of 90 dB It also prevents switching of the attenuator when the modulation is turned on or off Note that setting attenuator mode ELECTRONIC automatically sets the ALC mode to TABLE 12 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ Therefore the next two commands are not necessary in principle SOUR POW ALC O SOUR POW ALC S FF EAR OFF Sets ALC mode TABLE Recommended for uninterrupted level setting SOUR POW ALC TABL To ensure highest level accuracy in attenuator mode gt CAL LATT ELECTRONIC th
7. 20 dB Prevents attenuator switching when the modulation is turned on or off SOUR POW ALC OFF Sets ALC mode TABLE Recommended for SOUR POW ALC SEAR OFF uninterrupted level setting SOUR W3GP SETT TMOD BST M1CH64 Sets the parameters for the 3GPP test model SOUR FREQ 2 112559 Sets the carrier frequency to 2112 5 MHz lower end of the 3GPP downlink band OUTP STAT ON The RF output has to be switched on before storing the Fast Restore states RST sets the output to OFF SYST SSAV 1 Saves the first CW setting SOUR FREQ 2 1175e9 Sets the carrier frequency to 2117 5 MHz SYST SSAV 2 Saves the second CW setting continue SOUR FREQ 2 1675e9 Sets the carrier frequency to 2167 5 MHz upper end of the 3GPP downlink band SYST SSAV 12 Saves the last CW setting SOUR FREQ 2 112569 Sets the carrier frequency to 2112 5 MHz lower end of the 3GPP downlink band SOUR W3GP STAT ON Calculates and turns on the 3GPP signal SYST SSAV 13 Saves the first 3GPP signal setting 2112 5 MHz SOUR FREQ 2 1175e9 Sets the carrier frequency to 2117 5 MHz SYST SSAV 14 Saves the second 3GPP signal setting 2117 5 MHz continue SOUR FREQ 2 1675e9 Sets the carrier frequency to 2167 5 MHz upper end of the 3GPP downlink band SYST SSAV 24 Saves the last setting with 3GPP on SOUR FREQ 2 1125e9 Sets the initial and final state This is useful to match SYST SSAV 25 user interface and hardware state after running a Fast Resto
8. LF output Fast Restore does not affect the baseband modules If a baseband module is switched on before using RESTORE commands it will remain on until it is explicitly switched off by a normal IEC IEEE command Fast Restore can however switch from CW to modulated signals and back by turning on or off the I Q modulator without setting baseband modules So it is possible to change baseband settings with normal commands and then use the same RESTORE settings again This works with 3GPP IS 95 downlink ARB mode and vector modulation for example GSM EDGE however requres different RESTORE states because the powerramping is done partly by RF modules as is the case for all modulations where powerramping indicated by PRAMP is active Operation Commands SYSTem SSAVe 1 n n being the number of available memory locations Saves the current device setting at the memory location indicated SYSTem SREStore 1 n n being the number of available memory locations Loads a device status that was stored using the SySTem SSAVe command RESTORE lt least significant byte gt lt most significant byte gt This command has the same effect as the SyYSTem SREStore command The setting time however is 300 us shorter It is optimized for highest speed and does not comply with the SCPI syntax regulations Exactly 3 bytes are transmitted including the which is the identifier of this command With the last byte EOI has to be activated
9. OPE menu BLANK This output supplies a signal 0 V 5 V to blank the settling process by means of pulse modulation or AM The signal can also be used to synchronize other instruments The polarity of the signal can be set in the UTILITIES AUX I O BLANK POLARITY menu MARKER At the first step of the LIST mode this output provides an approx 200 us trigger signal immediately after blanking At small DWELL times this signal can be used for an accurate synchronization to trigger other devices and shows the first stable output frequency The delay to the fed in signal at the TRIGGER input for EXT SINGLE or EXT STEP is 1 5 to 2 ms and has a jitter of 0 5 ms 11 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ TRIGGER Input BLANK Output MARKER Output Frequency Fig 3 1 MARKER and BLANK signals in LIST mode In this example the list contains different frequencies and is operated in EXT STEP mode Every signal at the TRIGGER input makes the SMIQ step to the next list entry next frequency The BLANK signal is high during the frequency transitions until the target frequency is settled The MARKER signal appears once when the state of the first list entry is reached and stable Application examples Fast level sweep in a 90 dB range Problem Sweep a CW signal at 2 GHz once from 0 dBm to 90 dBm and backwards in 10 dB steps the step time is 3 ms This is not possible with the normal level sweep where the
10. ST CLS Sets the instrument to a defined state Note that RST switches off the RF output SOUR POW 10 Sets the RF level to 10 dBm OUTP AMOD FIX Sets attenuator mode FIXED for uninterrupted level settings in a range of 20 dB Prevents attenuator switching when the modulation is turned on or off SOUR POW ALC OFF Sets ALC mode TABLE Recommended for SOUR POW ALC SEAR OFF uninterrupted level setting SOUR W3GP SETT TMOD BST M1CH64 Sets the parameters for the 3GPP test model SOUR IS95 MODE FLIN18 Sets the parameters for the cdmaOne signal in this SOUR IS95 PRES case a predefined 9 code channel scenario SOUR FREQ 2 1125E9 Sets the carrier frequency to 2112 5 MHz lower end of the 3GPP downlink band OUTP STAT ON The RF output has to be switched on before storing the Fast Restore states RST sets the output to OFF Rohde amp Schwarz Fast remote control of SMIQ SYST SSAV 1 Saves the first CW setting SOUR FREQ 2 1175e9 Sets the carrier frequency to 2117 5 MHz SYST SSAV 2 Saves the second CW setting continue SOUR FREQ 2 1675e9 Sets the carrier frequency to 2167 5 MHz upper end of the 3GPP downlink band SYST SSAV 12 Saves the last CW setting SOUR FREQ 2 112569 Sets the carrier frequency to 2112 5 MHz lower end of the 3GPP downlink band SOUR W3GP STAT ON Calculates and
11. as delimiter The memory location is binary coded in the 2 bytes indicated 1GP55_0E 3 Rohde amp Schwarz Fast remote control of SMIQ Example RESTORE at memory location 268 gt 010C hex corresponds to the following binary command 00100001 00001100 0000 0001 Y hex 0C hex 01 Binary coded bytes usually cannot be written as printable ASCII characters When programmed in C the above command has the following form char sendstring 3 0x0C 0x01 In BASIC the command string to be output is as follows CHR 12 CHR 1 The pros for CHR are decimal numbers therefore 12 for OC hex Since binary coded bytes can also have the value of the LF line feed character which is interpreted as a delimiter switch over to only EO as delimiter by selecting SYSTem COMMunicate GPIB LTERminator EOT prior to using this command Call up and termination of operating mode After a RESTORE the database no longer reflects the device setting which means that e the displayed values are no longer relevant e the desired result is not obtained by a query of setup values e normal setting commands may not be executed properly It is therefore recommended either to use the RST command or to store the device setting prior to using the first RESTORE command by means of the SYSTem SSAVe n command and to restore it after the last RESTORE command using SYSTEM SRESTore n The database and the device setting will then ma
12. ese self calibrating routines should be called up at the beginning and after temperature variations of more than 5 degrees WAI Ensures that the next command is only executed after the calibration is complete Alternative check status with OPC SOUR LIST SEL LEVSWP Selects the list called LEVSWP If there is no list of this name a new list is created SOUR LIST FREQ 2GHz Generates the frequency entries SOUR LIST DWEL 3e 3 Sets the dwell time to 3 ms SOUR LIST POW OdBm 10dBm Generates the level entries 20dBm 30dBm 40dBm 50dBm 60dBm 70dBm 80dBm 90dBm 80dBm 70dBm 60dBm 50dBm 40dBm 30dBm 20dBm 10dBm OdBm OUTP STAT O The RF output has to be switched on before learning the list RST sets the output to OFF SOUR LIST LEAR Determines the hardware setting of the entire list This command has to be sent after every change of the list SOUR FREQ MODE LIST Activates list mode in SINGLE mode The instrument SOUR LIST MODE AUTO now waits for a trigger command Note that SMIQ sets TRIG LIST SOUR SING the frequency and level values of the last list entry in this waiting state The first list state is not set until a trigger event is received TRIG LIST IM Runs the list once SOUR FREQ MODE CW Switches off the list mode Note Always leave list mode before changing other hardware parameters Frequency hopping with GSM EDGE Problem Generate a GSM frame with
13. for a receiver test The generator shall step through the entire band in 5 MHz steps The signal level shall be 10 dBm Note Options SMIQB20 SMIQB11 and SMIQB45 are required for this example Solution The most time consuming process is the calculation of the 3GPP signal Without Fast Restore this has to be done every time the 3GPP state is switched on Therefore it is our goal to do this calculation only once We first save the Fast Restore states with CW signals Afterwards we calculate the 3GPP signal with normal IEC IEEE commands and save the Fast Restore states with the modulation active Then we run through the frequencies and switch between CW and 3GPP signals with RESTORE commands This does not change the 3GPP state only the I Q modulator is switched on or off Therefore we avoid the time consuming recalculation of the 3GPP signal As the initial baseband state 3GPP is on we should also terminate with a 3GPP signal running The commands for the entire procedure are as follows 5 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ Command Remarks Preparation RST CLS Sets the instrument to a defined state Note that RST switches off the RF output SOUR POW 10 Sets the RF level to 10 dBm OUTP AMOD FIX Sets attenuator mode FIXED for uninterrupted level settings in a range of
14. le 3 1 LIST mode Example of a list me ron oo 0002 575 MHz 13 dBm Fe ooo ee 9 Rohde amp Schwarz Fast remote control of SMIQ Running LIST mode The following LIST operating modes are available AUTO Run from the beginning to the end of the list with automatic restart at the beginning If another mode was activated prior to the AUTO operating mode continuation is made from the current index IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE AUTO TRIG LIST SOUR AUTO SINGLE Single run from the beginning to the end of the list If SINGLE is selected the run is manually executed with the function EXECUTE SINGLE LIST gt IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE AUTO TRIG LIST SOUR SING STEP Step by step manual processing of the list Activating STEP stops a list running and the cursor wraps to the indication value of CURRENT INDEX The list can now be controlled upwards or downwards in discrete steps using the rotary knob or the numeric keys IEC IEEE bus commands SOUR FREQ MODE LIST SOUR LIST MODE STEP TRIG LIST SOUR SING The first two commands set the operating mode to STEP Every command TRIG LIST SOUR SING leads to the next position of the list EXT SINGLE Single run from the beginning to the end of the list as with SINGLE but triggered by an external trigger signal TRIGGER input on the rear panel see
15. mation s osinean etana iainta Euse EN E E aiaia Teada i a eak 15 1 Overview Short setting times are among the most important criteria when it comes to choosing the right signal generator especially in production With its extremely short setting times for frequency lt 3 ms and level lt 2 5 ms the R amp S SMIQ Vector Signal Generator family is best suited to meet the requirement In addition SMIQ provides two special modes where the setting times can be further reduced The Fast Restore mode is a special feature for remote controlling the generator Device settings can be saved and recalled very quickly via the IEC IEEE bus using special commands The Fast Restore commands directly address the instrument modules the database of the SMIQ is bypassed leading to a very high setup speed Frequency and level settings can be performed in less than 800 us The Fast Restore mode is not restricted to frequency and level settings nearly all RF and general device parameters can be set The LIST mode provides even faster frequency and level settings lt 500 us A sequence of freely selectable frequency and level points can be executed either automatically or triggered by an external device or the internal baseband section Triggering via the IEC IEEE bus is also supported This Application Note explains both the Fast Restore mode and the LIST mode and gives some application examples 2 SMIQ Fast Restore Mode Working principle Device se
16. meslot 0O parameters e g TSC change the TSC in timeslot 1 see SMIQ user manual for details SOUR GSM STAT ON Activates the GSM EDGE system SOUR LIST SEL GSMHOP Selects the list called LEVSWP If there is no list of this name a new list is created SOUR LIST FREQ 890 2MHz 890 8MHz Generates two frequency entries with 600 kHz spacing SOUR LIST POW 10dBm Generates the level entry OUTP STAT O The RF output has to be switched on before learning the list RST sets the output to OFF SOUR LIST LEAR Determines the hardware setting of the entire list This command has to be sent after every change of the list SOUR FREQ MODE LIST z g SOUR ET UMD STET Activates list mode in HOP mode The instrument now waits for the hop trigger from the GSM EDGE system TRIG LIST SOUR HOP 4 f Each trigger event causes a step to the next list entry Note that SMIQ sets the frequency and level values of the last list entry in this waiting state The first list state is not set until a trigger event is received This will not happen until the GSM EDGE system is started TRIG DM IMM Starts the GSM EDGE system SOUR FREQ MODE CW Switches off the list mode Always leave the list mode before changing other hardware parameters 1GP55_0E 14 Rohde amp Schwarz Fast remote control of SMIQ 4 References 1
17. r mode AUTO then switch to attenuator mode FIXED or ELECTRONIC OUTPut AMODe FIXed or ELECtronic For details of the SMIQ s level setting modes see reference 4 e The time for switching on or off I Q modulation can also be decreased using the fast I Q transition mode SOURce DM 1Q TRAN FAST In this mode the I Q modulator is never switched off the CW signal is generated by a baseband signal with constant voltage U 0 5 V Ua 0 V As the spectral purity of the CW signal is slightly decreased this mode should only be used when fast transitions between I Q modulated and CW signals are required The fast transition mode works with VECTOR MOD DIGITAL MOD and DIGITAL STD standards However the mode makes no sense when changing the baseband signal takes more time than switching the I Q modulator as for example with WCDMA 3GPP or ARB mode Note that the fast I Q transition mode requires a baseband module to be set which is only possible with normal IEC IEEE commands In most cases RESTORE commands will be faster than the fast I Q transition mode e Since the module setting depends on the temperature of the unit any temperature variation of more than 5 C should be avoided between storage and call up to ensure the accuracy of the unit Application examples Switching between CW and modulated WCDMA 3GPP Problem Provide a WCDMA 3GPP signal and afterwards a CW signal in the 3GPP downlink band e g an interfering signal
18. range of the instrument The specified range of the level covers a 90 dB range If the permissible variation range is exceeded the level accuracy decreases If the level range exceeds 20 dB SMIQ switches to attenuator mode ELECTRONIC Otherwise attenuator mode FIXED is used Stepping through the list can be triggered by an external TTL signal The LIST mode allows even faster level or frequency variations than the Fast Restore mode However LIST mode includes only the parameters RF level and RF frequency Operation Creating a list Up to 10 lists can be created The total number of possible list entries in all lists depends on the SMIQ version and the options installed The number of remaining entries is indicated in the menu LIST gt FUNCTION gt EDIT VIEW The command SOUR LIST FREE returns two values first the free memory in numbers of entries then the number of entries already used Each list is identified by a separate name and selected via this name Each list consists of a frequency power and dwell content The dwell time is set once per list The number of entries for frequency and level must be equal However if a parameter has just one value throughout the entire list it is sufficient to set this value once Note After generating modifying or changing a list in the LIST mode the LEARN function must be executed to ensure that the new settings are transferred to the hardware IEC bus short command LIST LEAR Tab
19. re sequence Note that the modulation is active in this state Running the sequence Runs through the CW states I Q modulator off SYST SRES 1 state 1 SYST SRES 2 state 2 SYST SRES 12 state 12 Runs through the states with 3GPP signal I Q modulator on SYST SRES 13 state 13 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ Hoh Gollan roe drop eH SRES 24 SRES 25 state 24 initial state The following settings among others are stored in the Fast Restore states 1 2 1125 GHz 10 dBm I Q modulator off 2 2 1175 GHz 10 dBm I Q modulator off 12 2 1675 GHz 10 dBm I Q modulator off 13 2 1125 GHz 10 dBm I Q modulator on 14 2 1175 GHz 10 dBm I Q modulator on 24 2 1675 GHz 10 dBm I Q modulator on 25 2 1125 GHz 10 dBm I Q modulator on Note the Fast Restore states can be restored in any order You should only terminate the sequence with a Fast restore state where the I Q modulator is switched on in this case state 25 Switching between different digital modulations and CW Problem Same as before this time with an additional run with a cdmaOne IS 95 signal Note Options SMIQB20 SMIQB11 SMIQB42 and SMIQB45 are required for this example Solution Similar to example 1 To add the IS 95 signal we use additional normal IEC IEEE commands Command Remarks Preparation R
20. tch again No other commands are required to activate or deactivate this mode Alternative use with other IEC IEEE Bus commands The alternative use of the RESTORE commands SYSTem SREStore or and normal IEC IEEE bus commands is e useful with digital modulation First the baseband signal is configured by means of normal commands and digital modulation is switched on Then digital modulation can be switched on off using the RESTORE commands e possible for all commands that do not affect the RF output signal eg SYSTem UNIT e normally not possible for all the functions listed in the left column of Table 2 1 In case of doubt we recommend testing 1GP55_0E 4 Rohde amp Schwarz 1GP55_0E Fast remote control of SMIQ Synchronization signal In Fast Restore mode a synchronization signal is available at the rear panel BLANK connector to synchronize other devices The BLANK signal is high during settling of the RF output signal and low in the settled state The BLANK polarity can be changed in the menu UTILITIES AUX I O Additional recommendations e Ifthe mechanically switched attenuator is switched over by a RESTORE command the setting time increases by 15 ms This can be avoided by setting attenuator mode FIXED or ELECTRONIC for interruption free level setting prior to storing the setting To get the desired level setting range set the level to the highest desired value in attenuato
21. ttings can be saved and recalled very quickly via the IEC IEEE bus using the commands described below Up to 4000 memory locations are available depending on the SMIQ version and the options installed In contrast to the normal SAVE RECALL function only the setting data of the modules is stored in the Fast Restore mode Restoring by means of the SYSTem SREStore or command has an immediate effect on the modules The database which stores all entries and delivers the display data is bypassed The result is a very high setup speed The Fast Restore commands have an effect on almost all RF and general device settings see Table 2 1 1GP55_0E 1 For f gt 3 3 GHz the setting time is less than 700 ps 2 Rohde amp Schwarz Fast remote control of SMIQ Table 2 1 Device settings in Fast Restore mode Device settings supported by Fast Restore Device settings not supported by Fast Restore Frequency including reference oscillator baseband signal of digital modulation and digital standards Level including mech switched attenuator Settings for fading noise and distortion user correction and ALC modes Functions not affecting the RF output signal Analog modulation eg commands under SyYSTem or UNIT except for SYSTem PRESet Vector modulation Sweep Switch on off digital modulation ARB mode List mode or digital standards Memory sequence Switch on off fading noise or distortion LF generator and
22. turns on the 3GPP signal SYST SSAV 13 Saves the first 3GPP signal setting 2112 5 MHz SOUR FREQ 2 117569 Sets the carrier frequency to 2117 5 MHz SYST SSAV 14 Saves the second 3GPP signal setting 2117 5 MHz continue SOUR FREQ 2 1675e9 Sets the carrier frequency to 2167 5 MHz upper end of the 3GPP downlink band SYST SSAV 24 Saves the last setting with 3GPP on As we mix normal and RESTORE commands it is better to terminate with a RST command Therefore we do not save an initial state Running the sequence Runs through the CW states I Q modulator off SYST SRES 1 state 1 SYST SRES 2 state 2 SYST SRES 12 state 12 Runs through the states with 3GPP signal I Q modulator on SYST SRES 13 state 13 SYST SRES 24 state 24 SOUR IS95 STAT ON Switches on the cdmaOne signal The 3GPP signal is turned off automatically Runs through the states with cdmaOne signal I Q modulator on SYST SRES 13 state 13 SYST SRES 24 state 24 RST CLS Resets the unit to make sure that database and device settings match again 1GP55_0E Rohde amp Schwarz Fast remote control of SMIQ 3 SMIQ List Mode 1GP55_0E Working principle A sequence of predefined frequency and level points is executed in LIST mode similar to a sweep In contrast to a sweep a list with freely selectable pairs of values frequency and level can be generated The specified range of the frequency comprises the entire adjustable frequency
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