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R&S FSW WLAN Application User Manual

1. INPUt SE LSC trt c Ro INSTrument CREate DUPLicate ueneno ttt etant eaten rne aa Be daa e dasa Y parer epa EA 132 INSTrument CREate REPLEaCce eve ts iier ede pda ice t sen cele coe oed e dece aue e edad 133 INSTrument CREate NEW 132 INS Trumerit KEE 133 INSTr ment B Rr 133 INSTrumentRENamie ttti d eh p i aet e rere B feria v odere e tee 135 INS Tr ment SELSct oce terrre e dean heise A Divae AE vi sees bes cs vende EE 135 REESE RU N User Manual 1173 9357 02 06 243 R amp S FSW K91 List of Remote Commands WLAN LAYOUEADD WINDOW c 186 Eet IR ee KEE 188 LAYout IDENtify WINDOW rs S 188 EAYoUt REMoVeE WINDOW eder eoe n tarte rarae ea da lieve tas tpe tree n n TER Re 188 LAvoutREPL acel WINDowl tenete nnn inns tenes n resins e eres nnns insit n nnns in nnis 189 EAYOUESPLEIGF ves iecit eor er A OTREO FEYTPOTE IU LIEU WR NR FEE A EEEY ER EEUR YS 189 LAYout WINDowsn ADD eei eret ni xi xe n o a n CER Eaa ea Ee iiaae dE re Ru 190 LAYGUEWINDowsn IDEN Ufy aure rte eere d terere ped aere rere a edd eee e dat 191 LAvoutWiNDow nz REMove enne een esit nrnns ien rnnr sin tnni sid ent s set enn sse nent sir ne EESE EEEE EEan LAvoutWiNDow nz REPLACE eene nnner et hnnte dh rentis n iaa iia ana i aeia MME Moty LOAD JO
2. 5 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Send Trigger Output Type Trigger 2 3 Sends a user defined trigger to the output connector immediately Note that the trigger pulse level is always opposite to the constant signal level defined by the output Level setting e g for Level High a constant high signal is output to the connector until the Send Trigger button is selected Then a low pulse is sent Which pulse level will be sent is indicated by a graphic on the button Remote command OUTPut TRIGger lt port gt PULSe IMMediate on page 159 5 3 4 3 Frequency Settings Frequency settings for the input signal can be configured via the Frequency dialog box which is displayed when you do one of the following e Select the FREQ key and then the Frequency Config softkey e Select Input Frontend from the Overview and then switch to the Frequency tab Freque Center 13 25642 25 GHz Center Freg Stepsize 1 0 MHz Frequency Offset Value 0 0 Hz e ME MM E CLE 77 Center E Ee EE 77 Fregueney OffS Gb Lora ee dee cete depende eite dde e e Rue ele ea 78 Center Defines the normal center frequency of the signal The allowed range of values for the center frequency depends on the frequency span fmax and SpanNmin are specified in the data sheet Remote command SENSe FREQuency CENTer on page 145 Center Frequency Stepsize
3. M 163 Evaluation Rango m 172 UE Eu T 178 nnd Uo 180 EE itc ero ERA aa Eee ddan ede 183 9 5 1 Signal Description The signal description provides information on the expected input signal Useful commands for describing the WLAN signal described elsewhere SENSe FREQuency CENTer on page 145 Remote commands exclusive to describing the WLAN signal ie Le cq o Em 141 CONFigure STANdard Standard This remote control command specifies which WLAN standard the option is configured to measure The availability of many commands depends on the selected standard Parameters Standard 0 6 8 0 IEEE 802 11a 6 IEEE 802 11n 8 IEEE 802 11ac RST 0 Manual operation See Standard on page 72 User Manual 1173 9357 02 06 141 R amp S9FSW K91 Remote Commands for WLAN Measurements Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance 9 5 2 Configuring the Data Input and Output 9 5 2 1 LEE dee 142 e Contiguring the OUIDUIS ciere CAE 144 RF Input INbPut ATTenuation PbOTechonRE Get 142 E r ere Tel E ES 142 INPut FIET r HPASSESTATe reiten euren acce s t eren e eene e eR ERR Re readies 142 INPUT Pe VIG STATE OE 143 INPUEIN PGR EEN 143 INPUR SBC T N 1
4. eene 60 4 6 Receiving Data Input and Providing Data Output EEN 61 4 7 Preparing the R amp S FSW for the Expected Input Signal Frontend Parameters 62 4 8 Triggered measurements eeeeeeesseeeeennnn enne nnne nennen nnn nennen nennen 63 genis mercem 66 5 4 Multiple Measurement Channels and Sequencer Function 66 5 2 Display Configuration criteri VEER SSES 68 5 3 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance 68 5 4 Frequency Sweep Measurements eeeeseeeseeseeeneeeneene nennen nennen nnn nnn 114 25 7 e M M 119 7 How to Perform Measurements in the WLAN Application 120 7 1 How to Determine Modulation Accuracy Flatness and Tolerance Parameters for WLAN SiG Mal rcc 120 T User Manual 1173 9357 02 06 3 R amp S9FSW K91 Contents 7 2 8 1 8 2 9 1 9 2 9 3 9 4 9 5 9 6 9 7 9 8 9 9 9 10 9 11 9 12 A 1 A 2 How to Determine the OBW SEM ACLR or CCDF for WLAN Signals 121 Optimizing and Troubleshooting the Measurement 123 Optimizing the Measurement Results eeeeeeeeeeneeeeeeneenennn nnn 123 Error Messages and WarningS ccccesseeeenceeeeeeeseeeeeseeeeeeeseeeeeseeeeeeeeseeenseeeeeee
5. 145 SENSe FREQ uency GEN Ter STEP irr reete te irte e datei eee dit e ptite Ee 145 IGENZGe IEREOuencv CENTer STEP AUTO 145 SENSe EREQU nCcy OEFSeLt eec edd e ie a pde da Da e do de e gv pd tpe c d 146 EI MET RP R SENSe SWEep COUNt is I SENSe SWEep TIME tate rtt oct iei tear decr tuas o de D dg d E a RR RIF dg SENSe TRACkirig EEV6l oett ere rni diet p a eget tbe edendo ce e edet 162 SENSe TRACking PHASe esses enne nnne nne n nne tn ee nne tnnt etes etes ene tes innen enn enne nnnnne 162 SENSe TRACking PILots SENSe TRACKING J IMB 2 crt tit trennt as aes eee deed ead ake R amp S FSW K91 Index A Block diagram IEEE 802 11a g OFDM sirisssinsincis rnirada 45 Abbreviations Signal processing IEEE 802 11a g OFDM 45 C Aborting il 113 Capture buffer AC DC coupling ssssssseeeeeeeenn nnn 74 nc H ACLR Capture time Configuring cdma2000 sse 115 Default ie Results Displayed ussssss Results remote sss 207 see also Measurement time Activating Carriers WLAN measurements remote 132 ninm 59 Additive white Gaussian noise AWGN sss 47 CCDF Adjacent channel leakage ratio Confi
6. PV d m P wg eqe Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Manual operation See Reference Level Settings on page 79 See Reference Level on page 80 DISPlay WINDow lt n gt TRACe Y SCALe RLEVel OFFSet Offset This command defines a reference level offset Parameters Offset Range 200 dB to 200 dB RST OdB Example DISP TRAC Y RLEV OFFS 10dB Manual operation See Reference Level Settings on page 79 See Shifting the Display Offset on page 80 INPut ATTenuation lt Attenuation gt This command defines the total attenuation for RF input If an electronic attenuator is available and active the command defines a mechanical attenuation see INPut EATT STATe on page 149 If you set the attenuation manually it is no longer coupled to the reference level but the reference level is coupled to the attenuation Thus if the current reference level is not compatible with an attenuation that has been set manually the command also adjusts the reference level This function is not available if the Digital Baseband Interface R amp S FSW B17 is active Parameters lt Attenuation gt Range see data sheet Increment 5 dB RST 10 dB AUTO is set to ON Example INP ATT 30dB Defines a 30 dB attenuation and decouples the attenuation from the reference level Usage SCPI confirmed Manual ope
7. P le PM Retrieving Results FETCHIBURSERMS MAXIRUITI 2 icd dre na seutu turn er haria X Ou ena gu a uda a Feet inpune Peer edad edd Dana 202 FEUCITBURSERMS MIBIIBETS iiid ere aa EDEN P EDU RR ERR URN MR ced Osa Aa 202 FETChBURSESYMBolerror AVERAge terr ate tet eate ee RR d e exe ERR OL eno ieee 203 FETCHBURSESYMBolerror MAXIIUI 53 2 2 5d nita eo natum nece naso eode er pace denn e Rhe Ri chis 203 FETCH BURSES MBO ror lu 203 i m 203 EI EISE 203 FETCh BURSt ALL This command returns all results from the default WLAN measurement Modulation Accuracy Flatness and Tolerance see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 The results are output as a list of result strings separated by commas in ASCII format The results are output in the following order Return values Results preamble power payload power gt min rms power gt average rms power max rms power gt peak powers min crest factor average crest factor gt lt max crest factor min frequency error gt lt average frequency error max frequency error min symbol error average symbol error max symbol error min IQ offset average IQ offset maximum IQ offset min gain imbalance average gain imbalance max gain imbalance mi
8. RUE SEVEN ER EE RIESEN ROUER DISPlay WINDow lt n gt TABLe ITEM DISPlay WINDow n TRACe Y SCALe RLEVel sse eene enne ne nennen neni 147 DlSblavf WiN Dow nzTRACevtGCALelbEVelOttzet eene 148 DiSblavfWiINDow nztZOOMAREA tnmen t nhnti sen nnes enn rnns sen r ensi intent s nn EEan EEEn seni 222 DISPlay WINDow n ZOOM MULTiple zoom AREA sessi 223 DiSblavfWiINDow nztZ0O0OMMUL Tiple zoomzGT ATe enne nennen enne enn 224 DISPlay WINDow lt n gt ZOOM STATe FERGh BURSCAL ces EEE FEIGCh BURSECOUNEUCALE LE ie cort better eere anc eda a ere te ivre yy a HE ve ERE E sa Eee e eR ed 198 jd slieH iB idee r 198 FETGh BURSECRESEMAXITTIUET 6 e cere regere yii rb ke X Ec ER EU FE VEA EET deeg 200 FETCH BURSECRESEMINImmUtTE ossis rrr renes e Dee ere ete e ene E ERR ENEE rrr 200 FETCh BURSt CRESt AVERage EETCh BURSEEVM ALEL AVERGAJQe 5 nier rrt Rn eee ORE rec Dre da et der dra 200 FETCh BURStEEVM ALL MAXimum esses nnne nennen nnnnr en rrnns sn nrnrs sen rtns sen EAEE sinit sien rnt nnn 200 FETCWBURSCEVM ALL MINIMUM iiir eror h ee enr cereo ho ns e YES ERE VAR SERERE EE FER YE EXE ENARA EE CYR EE ERE E PE 200 FETOhBURGGCEVM DATA AVERaOoe sosanna iiia eiiiai a aa iaa ddanik aaah 201 FETCh BURSEEVM DATA MAXIRmUITI euet ern eei e re ree ro retra re ca RE Ue eren e pa een ee 201 FETCh BURSt EVM DA
9. Numeric Suffixes Some keywords have a numeric suffix if the command can be applied to multiple instan ces of an object In that case the suffix selects a particular instance e g a measurement window Numeric suffixes are indicated by angular brackets n next to the keyword If you don t quote a suffix for keywords that support one a 1 is assumed EE User Manual 1173 9357 02 06 128 R amp SS9FSW K91 Remote Commands for WLAN Measurements mmE A T C a qe Introduction Example DISPlay WINDow lt 1 4 gt ZOOM STATe enables the zoom in a particular mea surement window selected by the suffix at WINDow DISPlay WINDow4 ZOOM STATe ON refers to window 4 9 2 4 Optional Keywords Some keywords are optional and are only part of the syntax because of SCPI compliance You can include them in the header or not Note that if an optional keyword has a numeric suffix and you need to use the suffix you have to include the optional keyword Otherwise the suffix of the missing keyword is assumed to be the value 1 Optional keywords are emphasized with square brackets Example Without a numeric suffix in the optional keyword SENSe FREQuency CENTer is the same as FREQuency CENTer With a numeric suffix in the optional keyword DISPlay WINDow lt 1 4 gt
10. ssssssssseseeee 142 Overview Configuring WLAN measurements 70 P Packet search IEEE 802 11a g OFDM eene 46 Parameters Fromtend E 62 Input signal 61 Blue 61 WEAN pc ET 13 Payload Channel estimation sessssssess 92 161 Length 109 110 173 Length source remote sese 173 Length source 109 Allee RC 47 Peak list Evaluation method sssssssseeeeeee 44 Peak vector error Measurement range seseseeee 110 Peak Vector Error User Manual 1173 9357 02 06 250 R amp S9FSW K91 Index Phase drift coercet take de euge Dicen Tracking IEEE 802 11a g OFDM Phase tracking etes Pilot bit SrrOn Pate 4 ritratto xev Pilots Tor trackirig triente esterne nit 93 162 Power Interval Sareh iir tiere EE PPDU retirees ae Here ih VS TFEQUENGCY M vs time see PvT Power interval search Power sensors Trigger mode oct er tcrra 87 PPDU AbbreviatiOln a rtr tr ener Amount to analyze D Amount to analyze remote ssssuss 174 Analysis mode sss 94 97 104 Analyzed 10 59 Channel bandwidth 94 95 97 98 102 104 105 166 Count remote etit etate tet estes 198 Currently analyzed
11. U uu eee ees Starting a Measurement Now you can send the ABORt command on the remote channel performing the mea surement Example ABOR INIT IMM Aborts the current measurement and immediately starts a new one Example ABOR WAI INIT IMM Aborts the current measurement and starts a new one once abor tion has been completed Usage SCPI confirmed INITiate CONTinuous State This command controls the sweep mode Note that in single sweep mode you can synchronize to the end of the measurement with OPC OPC or WAI In continuous sweep mode synchronization to the end of the measurement is not possible Thus it is not recommended that you use continuous sweep mode in remote control as results like trace data or markers are only valid after a single sweep end synchronization For details on synchronization see the Remote Basics chapter in the R amp S FSW User Manual If the sweep mode is changed for a measurement channel while the Sequencer is active see rNiTiate SEQuencer IMMediate on page 195 the mode is only considered the next time the measurement in that channel is activated by the Sequencer Parameters State ON OFF 0 1 ON 1 Continuous sweep OFF 0 Single sweep RST 1 Example INIT CONT OFF Switches the sweep mode to single sweep INIT CONT ON Switches the sweep mode to continuous sweep Manual operation See Continuous Sweep RUN CONT
12. sess 14 15 Demodulatioti 5 2 nere eren 93 Displayed E EVM Direct rient ri etie 20 Extension Spatial Streams IEEE 802 11 n 107 163 Eormmab rne d ser 94 97 102 104 Format default rt rre rtt teens 69 Format remote sssssssssssesese 168 169 Guard interval length IEEE 802 11 n ac 101 107 164 165 Level EMOS iit terrre ihres 93 162 Maximum length remote sssssssss 177 Minimum length remote ssessssssss 177 Modulation a Modulation IEEE 802 11 ai 96 103 Modulation IEEE 802 11 n ac 98 105 Modulation remote Ness IEEE 802 11 n Mr Nsts IEEE 802 11 ac Payload lerigth 2 ette Payload length remote sssssssssss 173 Phase drift 3 Physical channel A 14 15 ull 93 162 RECOGNIZED serres an aipa aa 14 15 59 Signal field 35 94 97 104 170 STBC IEEE 802 11 ac n 99 106 166 TIMING GIONS oido roter eee sette ie Total analyzed VC WEE Preamble Channel estimation sess 92 161 Preamplifier SENG ice nd an cet etr 82 Get 82 Presetting Channels araid eere gate ETRAS Default values E Dicendum Protection RE Ile 15d ener ites Acne Sete eit 61 RF input remote ccccceeceeeceeeeeeeeeeeeeeeee
13. 92 162 Pilots 93 162 PPDU levels 93 162 PPDU timing 92 163 Quadrature phase angle I Q EET 18 Quadrature offset 14 Status bits 224 Symbol timing MeL areas 14 Estimates Signal processing IEEE 802 11a g OFDM 46 Estimating Channels IEEE 802 11a g OFDM 51 Evaluation methods Frequency sweep measurement sssissrrrsreresee 42 Dcus 186 Trace data ioci trarre 212 WLAN E 21 Evaluation range bcc Result displays sg SONGS EE EVM AU CANGIGNS cscs E 14 Calculating IEEE 802 11a g OFDM 51 Calculating NL AN 20 Data carriers 14 Data carriers limit check result remote 204 UO diagram IEEE 802 11b g DSSS Limit check result remote sssssssse 204 Limits remota erre hee verti eerie 179 Optimizing 8 Pilot Catriers c nre rentrer innt 14 Pilot carriers limit check result remote 205 PPDU direct B T c M vs carrier result display ssses 26 vs carrier trace data vs chip result display sssssseeeeeess 27 vs symbol result display sssesssss 27 Exp
14. eere rahe rente trn t ene ege a une 154 TRlGoert SGtOuencell EVel DBbower ktt tn ttnt ut EnA EEE EEEE EAEN EEAEENEA EEEn EAnEa En tEe eenen 154 TRIGger SEQuence LEVel IFPower esee nretnr inrer eterne 155 TRIGger SEQuence LEVel IQPOWer rt rere nnn rne terne tnnt therein e Eye anale 155 TRIGger SEQuence LEVel RFPoOwer esee eene nennen nenne nnnn nennen enne nnns nnns 156 TRIGger SEQuence LEVel EXTernal port esses enne e iied 154 TRIGger SEQuence MOPBE ooi eit ener eo sa dee a i EXE an rude ee a aA TRIGger SEQuence SLOBe 1r rr nme aerae erano ERE nea E ERR e o EE ea ako ra tke aaa ugs TRIGger SEQuence SOURce TRiGger SEQuence TIME RIN Tetval 5 onere notet rene tnn ck nuntur nant urna nein das 157 UNIT EVM E 203 UNIT GIMBAlan C65 icc M M 203 IEN Ge IAD lust CONEioure DUlPation nee etre e nennen 181 SENSe ADJust CONFigure DURation MODE ener nre nnr enne 182 SENSe ADJust CONFigure HYS Teresis LOWer sss ener rennen nnnm nennen 182 SENSe ADJust CONFigure HYSTeresis UPPer sse nre eee neret rennen 183 EIST HHI U e EEIN SENSe BANDwidth CHANnel AUTO TYPE SENSe BANDwidth RESolution FIL Ter GTATel enne 151 SENSe BURSt 010 0 RRRRRRRRRRRRRRRRERRRRERRERERRRRR 174 EISE e ee e E 174 SENSe DEMod GESTTimmat
15. 132 Coupling Input remote nerd erc 142 Crest Eactor icio rre reine c a AEE 14 D Data acquisition see Signal capturing sees 82 Data format aj M E Ee 210 Data input ep m 72 Data OUIDUL esche eegen erugeet 72 Data symbols Estimating IEEE 802 11a g OFDM 50 Number Y Number of displayed sse 10 ce E 109 173 Default values dij M 69 Demodulation BASICS 60 COMIQUIING EE 93 Configuring remote esee 163 Dependencies ell UE 60 BIETe Bee erm 11 Diagrams Evaluation method nennen Digital standard uus terne Channel bandwidths Bre Displayed eire ren hn reru t N Selecting e Selecting remote rne 141 Display Configuration softkey see 68 Understanding essei rer rr eee 10 Drop out time UIS cm 64 88 Duplicating Measurement channel remote 132 E Electronic input attenuation eeseeesessse 81 Errors Calculating parameters seseseeeieeeeereereerrerrrerrernen 49 Calculating parameters IEEE 802 11a g OFDM peru 51 Center frequency 14 d nm 20 Gain imbalance 14 17 UO offset 14 17 Oe 124 Phase drift
16. Physical vs Effective Channels i REAL 6 8 IMAG f sal saf Eo Symbol error vector magnitude 4 21 Verr v The advantage of this method is that no estimate of the reference signal is needed but the UO offset and gain imbalance values are not estimated in a joint estimation procedure Therefore each estimation parameter disturbs the estimation of the other parameter and the accuracy of the estimates is lower than the accuracy of the estimations achieved by Transmitter baseband filter Tx filter estimation If the EVM value is dominated by Gaus sian noise this method yields similar results as Cost function for signal parameters The EVM vs Symbol result display shows two traces each using a different calculation method so you can easily compare the results see EVM vs Symbol on page 27 4 2 3 Literature on the IEEE 802 11b Standard 1 Institute of Electrical and Electronic Engineers Part 11 Wireless LAN Medium Access Control MAC and Physical Layer PHY specifications IEEE Std 802 11 1999 Institute of Electrical and Electronic Engineers Inc 1999 2 Institute of Electrical and Electronic Engineers Part 11 Wireless LAN Medium Access Control MAC and Physical Layer PHY specifications Higher Speed Physical Layer Extensions in the 2 4 GHz Band IEEE Std 802 11b 1999 Institute of Electrical and Electronic Engineers Inc 1999 4 3 Physical vs Effective Channels
17. without unit SENSe FREQuency CENTer 159 would also set a frequency of 1 GHz Values exceeding the resolution of the instrument are rounded up or down If the number you have entered is not supported e g in case of discrete steps the command returns an error Instead of a number you can also set numeric values with a text parameter in special cases e MIN MAX Defines the minimum or maximum numeric value that is supported e DEF Defines the default value e UP DOWN Increases or decreases the numeric value by one step The step size depends on the setting In some cases you can customize the step size with a corresponding command Querying numeric values When you query numeric values the system returns a number In case of physical quan tities it applies the basic unit e g Hz in case of frequencies The number of digits after the decimal point depends on the type of numeric value Example Setting SENSe FREQuency CENTer 1GHZ Query SENSe FREQuency CENTer would return 1E9 In some cases numeric values may be returned as text e INF NINF Infinity or negative infinity Represents the numeric values 9 9E37 or 9 9E37 e NAN T User Manual 1173 9357 02 06 130 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 2 6 2 9 2 6 3 9 2 6 4 9 2 6 5 Introduction Not a number Represents the numeric value 9 91E37 NAN is returned in case of error
18. 26 26 denotes the channel index of the occupied sub carriers First the FFT of the LS is calculated After the FFT calculation the known symbol information of the LS sub carriers is removed by dividing by the symbols The result is a coarse estimate A of the channel transfer function In the next step the complex channel impulse response is computed by an IFFT Then the energy of the windowed impulse response the window size is equal to the guard period is calculated for each trial time Afterwards the trial time of the maximum energy is detected This trial time is used to adjust the timing Determing the payload window Now the position of the LS is known and the starting point of the useful part of the first payload symbol can be derived In the next block this calculated time instant is used to position the payload window Only the payload part is windowed This is sufficient because the payload is the only subject of the subsequent measurements In the next block the windowed sequence is compensated by the coarse frequency esti mate Af course This is necessary because otherwise inter channel interference ICI would occur in the frequency domain The transition to the frequency domain is achieved by an FFT of length 64 The FFT is performed symbol wise for each symbol of the payload nof symbols The calculated FFTs are described byr with e 1 nof symbols as the symbol index e k 81 32 as the channel index In cas
19. 68 Literature IEEE 802 11a g OFDM eee 52 User Manual 1173 9357 02 06 249 R amp S9FSW K91 Index Loading FUNCIONS e MP 114 Biel El 60 Log likelihood function IEEE 802 118 g OFDM cissie 49 Long symbol LS IEEE 802 11a g IOEDMI 46 Lower Level Hysteresis SOfFIKOV carden rtp Hr eta 112 M Magnitude Capture Isesultdisplay deeg tr terree 29 Trace data soraia EET 212 Marker Functions MEMU innordne ana nr cia eee e A AAA 68 Markers Configuration remote seen 221 Querying position remote esses 221 Table evaluation method sssuesss 43 Marker table Evaluation method eene 43 Maximizing Windows remote sessee 185 le cirea nentes BICI MERE Displayed Displayed information esses 100 107 Bc 170 Measurement channel Creating remote sees 132 133 135 Deleting remote nennen 133 Duplicating remote RS Querying remote ssss 133 Renaming remote rre 135 Replacing remote Selecting remote Measurements Frequency sWeep eer rr nente then 39 Big cq EE 39 RF AY POS e C eebe eege ge 39 Selecting ds Selecting remote eror enne 136 Setup displayed eerte Starting remote Ke Measurement time freu
20. 7 1 How to Determine Modulation Accuracy Flatness and Tolerance Parameters for WLAN Signals 1 Press the MODE key on the front panel of the R amp S FSW A dialog box opens that contains all operating modes and applications currently available on your R amp S FSW 2 Select the WLAN item Ga o WLAN The R amp S FSW opens a new measurement channel for the WLAN application 3 Select the Overview softkey to display the Overview for a WLAN measurement 4 Select the Signal Description button to define the digital standard to be used 5 Select the Input Frontend button and then the Frequency tab to define the input signal s center frequency The reference level is adapted automatically 6 Select the Signal Capture button to define how much and which data to capture from the input signal 7 Todefine a particular starting point for the FFT or to improve the measurement speed for signals with a low duty cycle select the Synchronization OFDM Demod button and set the required parameters 8 Selectthe Tracking Channel Estimation button to define how the data channels are to be estimated and which distortions will be compensated for 9 Select the Demod button to provide information on the modulated signal and how the PPDUS detected in the capture buffer are to be demodulated 10 Select the Evaluation Range button to define which data in the capture buffer you want to analyze LEE User Manual 1173 9357 0
21. Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS ro sc N Uo Error vector magnitude EVM IEEE 802 11b or g DSSS method EVM v Symbol error vector magnitude 4 15 In 2 a different algorithm is proposed to calculate the error vector magnitude In a first step the IQ offset in the l branch and the IQ offset of the Q branch are estimated sepa rately 0 X SEALY UO offset I branch 4 16 N 1 09 y IMAG v N v 0 1 Q offset Q branch 4 17 where r v is the measurement signal which has been corrected with the estimates of the timing offset frequency offset and phase offset but not with the estimates of the gain imbalance and UO offset With these values the gain imbalance of the I branch and the gain imbalance of the Q branch are estimated in a non linear estimation in a second step o 7 D REAL G 6 v 0 Gain imbalance I branch 4 18 R M e x IMAG tO o Gain imbalance Q branch 4 19 Finally the mean error vector magnitude can be calculated with a non data aided cal culation 4 N 1 WEE 4152 udi BS REAL v 0 g f 2 mcg al Gal Ver v v 0 i B a Mean error vector magnitude 4 20 The symbol error vector magnitude is the error signal magnitude normalized by the root mean square value of the estimate of the measurement signal power User Manual 1173 9357 02 06 57 R amp SS9FSW K91 Measurement Basics
22. User defined User defined settings define which PPDUs are analyzed This setting is automatically selected when any of the subsequent settings are changed to a value other than Auto Remote command SENSe DEMod FORMat BCONtent AUTO on page 170 PPDU Format to measure Defines which PPDU formats are to be included in the analysis Depending on which standards the communicating devices are using different formats of PPDUs are availa ble Thus you can restrict analysis to the supported formats Note The PPDU format determines the available channel bandwidths For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display Format column see Signal Field on page 35 Auto same type as first PPDU A1st The format of the first valid PPDU is detected and subsequent PPDUs are analyzed only if they have the same format Auto individually for each PPDU AI All PPDUs are analyzed regardless of their format Meas only M Only PPDUs with the specified format are analyzed LEE User Manual 1173 9357 02 06 104 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Demod all as D All PPDUs are assumed to have the specified PPDU format Remote command SENSe
23. e Parameter usage If not specified otherwise a parameter can be used to set a value and it is the result of a query Parameters required only for setting are indicated as Setting parameters Parameters required only to refine a query are indicated as Query parameters Parameters that are only returned as the result of a query are indicated as Return values e Conformity Commands that are taken from the SCPI standard are indicated as SCPI con firmed All commands used by the R amp S FSW follow the SCPI syntax rules e Asynchronous commands A command which does not automatically finish executing before the next command starts executing overlapping command is indicated as an Asynchronous com mand e Reset values RST Default parameter values that are used directly after resetting the instrument RST command are indicated as RST values if available e Manual operation If the result of a remote command can also be achieved in manual operation a link to the description is inserted Long and Short Form The keywords have a long and a short form You can use either the long or the short form but no other abbreviations of the keywords The short form is emphasized in upper case letters Note however that this emphasis only serves the purpose to distinguish the short from the long form in the manual For the instrument the case does not matter Example SENSe FREQuency CENTer is the same as SENS FREQ CENT
24. e Payload The useful data During signal processing PPDUs are recognized by their preamble symbols The rec ognized PPDUs and the information on the modulation used for transmission of the useful data are shown in the Signal Field result display see Signal Field on page 35 Not all of the recognized PPDUs must be analyzed Some are dismissed because the PPDU parameters do not match the user defined demodulation settings which act as a logical filter see also chapter 4 5 Demodulation Parameters Logical Filters on page 60 Others may be dismissed because they contain too many or too few pay load symbols as defined by the standard or due to other irregularities or inconsistency Dismissed PPDUs are indicated as such in the Signal Field result display Only the remaining valid PPDUs are actually analyzed The PPDUs to be analyzed are highlighted in the Magnitude Capture buffer display T User Manual 1173 9357 02 06 59 R amp SS9FSW K91 Measurement Basics Demodulation Parameters Logical Filters Then again the physical channel cannot always be determined for all analyzed PPDUs In this case results are only available for the effective channel see also chapter 4 3 Physical vs Effective Channels on page 58 4 5 Demodulation Parameters Logical Filters The demodulation settings define which PPDUS are to be analyzed thus they define a logical filter They can either be defined using specific values or
25. 0 Sweep starts earlier pre trigger Remote command TRIGger SEQuence HOLDoff TIME on page 153 Hysteresis Trigger Source Settings Defines the distance in dB to the trigger level that the trigger source must exceed before a trigger event occurs Settting a hysteresis avoids unwanted trigger events caused by noise oscillation around the trigger level This setting is only available for IF Power trigger sources The range of the value is between 3 dB and 50 dB with a step width of 1 dB For more information see chapter 4 8 2 Trigger Hysteresis on page 63 Remote command TRIGger SEQuence IFPower HYSTeresis on page 154 Trigger Holdoff Trigger Source Settings Defines the minimum time in seconds that must pass between two trigger events Trig ger events that occur during the holdoff time are ignored For more information see chapter 4 8 4 Trigger Holdoff on page 65 Remote command TRIGger SEQuence IFPower HOLDoff on page 153 Slope Trigger Source Settings For all trigger sources except time you can define whether triggering occurs when the signal rises to the trigger level or falls down to it Remote command TRIGger SEQuence SLOPe on page 156 Trigger 2 3 Defines the usage of the variable TRIGGER INPUT OUTPUT connectors where Trigger 2 TRIGGER INPUT OUTPUT connector on the front panel Trigger 3 TRIGGER 3 INPUT OUTPUT connector on the rear panel Trigger 1 is INPUT
26. CALCulate lt n gt UNIT POWer lt Unit gt This command selects the unit of the y axis The unit applies to all measurement windows Parameters lt Unit gt DBM V A W DBPW WATT DBUV DBMV VOLT DBUA AMPere RST dBm Example CALC UNIT POW DBM Sets the power unit to dBm Manual operation See Reference Level Settings on page 79 See Unit on page 80 CONFigure POWer AUTO lt Mode gt This command is used to switch on or off automatic power level detection When switched on power level detection is performed at the start of each measurement sweep Parameters lt Mode gt ON OFF ONCE RST ON Manual operation See Reference Level Settings on page 79 See Setting the Reference Level Automatically Auto Level on page 81 CONFigure POWer EXPected RF lt Value gt This command specifies the mean power level of the source signal as supplied to the instrument s RF input This value is overwritten if Auto Level mode is turned on Parameters lt Value gt Default unit DBM Manual operation See Reference Level Settings on page 79 See Signal Level RMS on page 80 DISPlay WINDow lt n gt TRACe Y SCALe RLEVel lt ReferenceLevel gt This command defines the reference level Example DISP TRAC Y RLEV 60dBm Usage SCPI confirmed Ee User Manual 1173 9357 02 06 147 R amp SS9FSW K91 Remote Commands for WLAN Measurements PEHEMGNSGENE EMEND IAMC PHa
27. DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 SENSe DEMod FORMat BANalyze on page 168 Channel Bandwidth to measure CBW Defines the channel bandwidth of the PPDUs taking part in the analysis Depending on which standards the communicating devices are using different PPDU formats and channel bandwidths are supported For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display CBW column see Signal Field on page 35 Auto same The channel bandwidth of the first valid PPDU is detected and subse type as first quent PPDUs are analyzed only if they have the same channel band PPDU Aist width Auto individu All PPDUs are analyzed regardless of their channel bandwidth ally for each PPDU Al Meas only Only PPDUs with the specified channel bandwidth are analyzed signal M Demod all All PPDUs are assumed to have the specified channel bandwidth as sig nal D Remote command SENSe BANDwidth CHANnel AUTO TYPE on page 166 MCS Index to use Defines the PPDUS taking part in the analysis depending on their Modulation and Coding Scheme MCS index Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display MCS colu
28. Defines the step size by which the center frequency is increased or decreased when the arrow keys are pressed When you use the rotary knob the center frequency changes in steps of only 1 10 of the Center Frequency Stepsize The step size can be coupled to another value or it can be manually set to a fixed value User Manual 1173 9357 02 06 77 R amp S9FSW K91 Configuration 5 3 4 4 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Center Sets the step size to the value of the center frequency The used value is indicated in the Value field Manual Defines a fixed step size for the center frequency Enter the step size in the Value field Remote command SENSe FREQuency CENTer STEP on page 145 Frequency Offset Shifts the displayed frequency range along the x axis by the defined offset This parameter has no effect on the R amp S FSW hardware or on the captured data or on data processing It is simply a manipulation of the final results in which absolute frequency values are displayed Thus the x axis of a spectrum display is shifted by a constant offset if it shows absolute frequencies but not if it shows frequencies relative to the signal s center frequency A frequency offset can be used to correct the display of a signal that is slightly distorted by the measurement setup for example The allowed values range from 100 GHz to 100 GHz The default setting is 0 Hz Note I
29. IEEE 802 11 n DGRF All PPDUs are assumed to have the PPDU format HT GF IEEE 802 11 n MVHT Only PPDUs with format VHT are analyzed IEEE 802 11 ac DVHT All PPDUs are assumed to have the PPDU format VHT IEEE 802 11 ac RST FBURSt SENS DEM FORM BAN BTYP AUTO TYPE FBUR User Manual 1173 9357 02 06 169 R amp SS9FSW K91 Remote Commands for WLAN Measurements RNEEMECAECIMCUCOI CCI U e H Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Manual operation See PPDU Format to measure on page 94 See PSDU Modulation to use on page 95 See PPDU Format to measure PSDU Modulation to use on page 102 SENSe DEMod FORMat BCONtent AUTO State This command determines whether the PPDUs to be analyzed are determined automat ically or by the user Parameters State ON The signal field i e the PLCP header field of the first recognized PPDU is analyzed to determine the details of the PPDU All PPDwUs identical to the first recognized PPDU are analyzed OFF Only PPDUs that match the user defined PPDU type and modu lation are considered in results analysis see SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 and SENSe DEMod FORMat BANalyze on page 168 Manual operation See PPDU Analysis Mode on page
30. Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt EEVM PILot AVERage FETCh BURStEVM PILot MAXimum FETCh BURStEVM PILot MINimum This command returns the average maximum or minimum EVM in dB for the pilot carrier For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt FERRor AVERage FETCh BURSt FERRor MAXimum FETCh BURSt FERRor MINimum This command returns the average maximum or minimum center frequency errors in Hertz For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt GIMBalance AVERage FETCh BURSt GIMBalance MAXimum FETCh BURSt GIMBalance MINimum This command returns the average maximum or minimum UO imbalance in dB For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only ERREUR RI a User Manual 1173 9357 02 06 201 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG MM C U M m m nQ s Retrieving Results FETCh BURSt IQOFfset AVERage FETCh BURSt IQOFfset MAXimum FETCh BURSt IQOFfset MINimum This command returns the average maximum or minimum UO offset in dB For details see chapter 3 1 1 Modulation Accur
31. The Minhold Average and Maxhold traces are displayed This result display is not available for single carrier measurements IEEE 802 11b g DSSS 4 EVM vs Carrier sl Mine2 Avge3 Max Carrier 250 50 1 Carrier Carrier 250 ERREUR RA M User Manual 1173 9357 02 06 26 R amp S FSW K91 Measurements and Result Displays El WLAN UO Measurement Modulation Accuracy Flatness and Tolerance The numeric trace results for this evaluation method are described in chapter 9 9 4 5 EVM vs Carrier on page 218 Remote command LAY ADD 1 RIGH EVC see LAYout ADD WINDow on page 186 Or CONFigure BURSt EVM ECARrier IMMediate on page 137 EVM vs Chip This result display shows the error vector magnitude per chip This result display is only available for single carrier measurements IEEE 802 11b g DSSS Since the R amp S FSW WLAN application provides two different methods to calculate the EVM two traces are displayed S EVM vs Chip ii Ww 2 EVM Chip 1 27651 6 Chip Chip 276516 e Vector Error IEEE shows the error vector magnitude as defined in the IEEE 802 11b or g DSSS standards see also Error vector magnitude EVM IEEE 802 11b or g DSSS method on page 57 e EVM shows the error vector magnitude calculated with an alternative method that provides higher accuracy of the estimations see also Error vector magnitude EVM R amp S FSW method on page 56 Remote command LAY A
32. ZO00M STATe DISPlay ZOOM STATe ON enables the zoom in window 1 no suffix DISPlay WINDow4 ZOOM STATe ON enables the zoom in window 4 9 2 5 Alternative Keywords A vertical stroke indicates alternatives for a specific keyword You can use both keywords to the same effect Example SENSe BANDwidth BWIDth RESolution In the short form without optional keywords BAND 1MHZ would have the same effect as BWID 1MHZ 9 2 6 SCPI Parameters Many commands feature one or more parameters If a command supports more than one parameter these are separated by a comma Example LAYout ADD WINDow Spectrum LEFT MTABle Parameters may have different forms of values LEE User Manual 1173 9357 02 06 129 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 2 6 1 Introduction e Numere V lll 8 iiie ien eni erheben n nna nena nean aha anra ne nk rh abra kernel na 130 e BOOlB3p Re eis Deine lea ed a 131 e Character Terasse En rene iaa ia vr eaa e Tere RC pee dre FEN ae NER Ee 131 e Chargclor Te a rere etr trance pande cha ER inque a Rad dotes Ra ar gea 131 e Black Dala see o EE a Ens Ebert ite e ae Mrs cusa E dedu 131 Numeric Values Numeric values can be entered in any form i e with sign decimal point or exponent In case of physical quantities you can also add the unit If the unit is missing the command uses the basic unit Example with unit SENSe FREQuency CENTer 1GHZ
33. e EEE standards 802 11a e EEE standards 802 11ac e EEE standards 802 11b e EEE standards 802 11g OFDM e EEE standards 802 119 DSSS e EEE standards 802 11n SISO The R amp S FSW WLAN application features Modulation measurements e Constellation diagram for demodulated signal e Constellation diagram for individual carriers e 1 Q offset and UO imbalance e Modulation error EVM for individual carriers or symbols e Amplitude response and group delay distortion spectrum flatness Further measurements and results e Amplitude statistics CCDF and crest factor e FFT also over a selected part of the signal e g preamble e Payload bit information This user manual contains a description of the functionality that is specific to the appli cation including remote control operation All functions not discussed in this manual are the same as in the base unit and are described in the R amp S FSW User Manual The latest version is available for download at the product homepage Installation You can find detailed installation instructions in the R amp S FSW Getting Started manual or in the Release Notes 2 1 Starting the WLAN Application The WLAN measurements require a special application on the R amp S FSW To activate the WLAN application 1 Press the MODE key on the front panel of the R amp S FSW User Manual 1173 9357 02 06 9 R amp S FSW K91 Welcome to the WLAN Application Understanding the Dis
34. responds to Auto individually for each PPDU MB5 Only PPDUs within a channel bandwidth of 5MHz are analyzed IEEE 802 11 a only MB10 Only PPDUs within a channel bandwidth of 10MHz are analyzed IEEE 802 11 a only MB20 Only PPDUs within a channel bandwidth of 20MHz are analyzed MB40 Only PPDUs within a channel bandwidth of 40MHz are analyzed IEEE 802 11 n ac only MB80 Only PPDUs within a channel bandwidth of 80MHz are analyzed IEEE 802 11 ac only MB160 Only PPDUS within a channel bandwidth of 160MHz are analyzed IEEE 802 11 ac only DB5 All PPDUs are analyzed within a channel bandwidth of 5MHz IEEE 802 11 a only DB10 All PPDUs are analyzed within a channel bandwidth of 10MHz IEEE 802 11 a only DB20 All PPDUs are analyzed within a channel bandwidth of 20MHz DB40 All PPDUs are analyzed within a channel bandwidth of 40MHz IEEE 802 11 n ac only DB80 All PPDUs are analyzed within a channel bandwidth of 80MHz IEEE 802 11 n ac only DB160 All PPDUs are analyzed within a channel bandwidth of 160MHz IEEE 802 11 n ac only RST FBURst Example SENS BAND CHAN AUTO TYPE MB20 EEUU ER e e A LL LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLIL A AALLUX User Manual 1173 9357 02 06 167 R amp S9FSW K91 Remote Commands for WLAN Measurements Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Manual operation See Channel Bandwidth to measure CBW
35. Activates a measurement channel for the WLAN application INST WLAN Selects the measurement channel named WLAN for example before executing further commands for that channel SYSTem PRESet CHANnel EXECute This command restores the default instrument settings in the current channel Use INST SEL to select the channel Example Usage Manual operation INST Spectrum2 Selects the channel for Spectrum2 SYST PRES CHAN EXEC Restores the factory default settings to the Spectrum2 channel Event See Preset Channel on page 71 User Manual 1173 9357 02 06 135 R amp SS9FSW K91 Remote Commands for WLAN Measurements Selecting a Measurement 9 4 Selecting a Measurement The following commands are required to define the measurement type in a remote envi ronment The selected measurement must be started explicitely see chapter 9 8 Start ing a Measurement on page 193 For details on available measurements see chapter 3 Measurements and Result Dis plays on page 13 rectangular filter with a relatively large bandwidth This measurement is selected when the WLAN measurement channel is activated The commands to select a different mea surement or return to the WLAN IQ measurement are described here CH The WLAN IQ measurement captures the UO data from the WLAN signal using a nearly Note that the CONF BURS ResultType IMM commands change the screen layout to disp
36. Flatness and Tolerance 3 Measurements and Result Displays The R amp S FSW WLAN application provides several different measurements in order to determine the parameters described by the WLAN 802 11 specifications For details on selecting measurements see Selecting the measurement type on page 66 Note for R amp S FSV and R amp S FSQ users o In comparison to the WLAN applications for R amp S FSV and R amp S FSQ spectrum analyzers the following measurements and result displays are not yet available e MIMO measurements e Power vs time for rising falling edges e Frequency error vs preamble e Phase error vs preamble WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 13 Frequency Sweep Measurement ceccceceeeeceecaeeeaceaeeeeeceeceeeceeeeeeeeeeeeeeeeees 39 3 1 WLAN UO Measurement Modulation Accuracy Flat ness and Tolerance The default WLAN UO measurement captures the UO data from the WLAN signal using a nearly rectangular filter with a relatively large bandwidth The UO data captured with this filter includes magnitude and phase information which allows the R amp S FSW WLAN application to demodulate broadband signals and determine various characteristic signal parameters such as the modulation accuracy spectrum flatness center frequency tol erance and symbol clock tolerance in just one measurement Other parameters specified in the WLAN 802 11 standard require a better signal to
37. R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Trigger Source Trigger Source Settings Defines whether a trigger is to be considered at all and if so which signal IF RF power sensor external signal etc will provide the trigger signal If a trigger source other than Free Run is set TRG is displayed in the channel bar and the trigger source is indica ted Remote command TRIGger SEQuence SOURce on page 156 Free Run Trigger Source Trigger Source Settings No trigger source is considered Data acquisition is started manually or automatically and continues until stopped explicitely Remote command TRIG SOUR IMM see TRIGger SEQuence SOURce on page 156 External Trigger 1 2 3 Trigger Source Trigger Source Settings Data acquisition starts when the TTL signal fed into the specified input connector on the front or rear panel meets or exceeds the specified trigger level See Trigger Level on page 88 Note The External Trigger 1 softkey automatically selects the trigger signal from the TRIGGER INPUT connector on the front panel For details see the Instrument Tour chapter in the R amp S FSW Getting Started manual External Trigger 1 Trigger signal from the TRIGGER INPUT connector on the front panel External Trigger 2 Trigger signal from the TRIGGER INPUT OUTPUT connector on the front panel Note Connector must be config
38. The data transmitted between a sender and the recipient is referred to as a space time stream Space time streams contain the coded data that is to be transmitted The trans mitted demodulated and decoded data is referred to as a bitstream In order to transmit the data one or more antennas are required by the sender and one or more antennas are required by the receiver For each space time stream at least one training field is included in every PPDU pre amble Each sender antenna transmits these known training fields The space time streams are then mapped to the receiver antennas The mapping of a space time stream to a receiver antenna is also referred to as an effective channel If the spatial mapping is known and the channel matrix is invertible the mapping of the receiver antenna to the sender antenna for a space time stream can be determined This mapping is referred to as a physical channel While the physical channels cannot always be determined the effective channel can always be estimated from the known training fields Thus for some PPDUS or measure T User Manual 1173 9357 02 06 58 R amp S9FSW K91 Measurement Basics 4 4 Recognized vs Analyzed PPDUs ment scenarios only the results based on the mapping of the space time stream to the Rx antenna effective channel are available as the mapping of the Rx antennas to the Tx antennas physical channel could not be determined If the physical channels can
39. Trigger e WEE 86 Trigger level remote ssssessesss 155 Impedance FROMM cc 143 STE ao APA 74 Importing FUNCIONS P isni a 114 et E EE 72 114 235 UO data remote sese 220 ic MC enn vedas 114 Input iere rot aunties Coupling default i Coupling remote s esee Overload Overload remote SGUINGS EE Signal parameters Source Radio frequency RF ssususs 73 Source Configuration softkey ss 73 Input sample rate AS saai Default oret ttr etr a aie Displayed ient iei Ree iinet iit FROMM cp Input sample rate ISR BefihitiOrt ire rte 230 Installation Inter channel interference ICI n errenneren 47 K Keys SPAN m M 68 L Level Ded eege a a Tracking IEEE 802 11a g OFDM Level error tracking Limits Defining remote ssessssse 178 EVM eet eg 179 EVM result rtm 204 EVM pilot carriers result 205 Freqeuncy error result 205 Frequency error 180 UO offset 180 UO offset result 205 Symbol clock error 180 Symbol clock error result sssseusss 205 Lines MI
40. Tx All TALL UO Offset IOFSset Gain imbalance GIMBalance Quadrature offset QOFFset PPDU power TPPower Crest factor TCFactor Receive channel Rx All RALL PPDU power RPPower Crest factor RCFactor Bitstream Stream All SALL Pilot bit error rate BPILot EVM all carriers SEACarriers EVM data carriers SEDCarriers EVM pilot carriers SEPCarriers Table 9 8 Parameters for the items of the Result Summary Global Result in table SCPI parameter Pilot bit error rate PBERate EVM all carriers EACarriers EVM data carriers EDCarriers EVM pilot carriers EPCarriers User Manual 1173 9357 02 06 192 R amp SS9FSW K91 Remote Commands for WLAN Measurements Starting a Measurement Result in table SCPI parameter Center frequency error CFERror Symbol clock error SCERror 9 8 Starting a Measurement When a WLAN measurement channel is activated on the R amp S FSW a WLAN IQ mea surement Modulation Accuracy Flatness and Tolerance see chapter 3 1 WLAN UO Measurement Modulation Accuracy Flatness and Tolerance on page 13 is started immediately However you can stop and start a new measurement any time Furthermore you can perform a sequence of measurements using the Sequencer see chapter 5 1 Multiple Measurement Channels and Sequencer Function on page 66 ABORU U 193 NTa
41. WEAN E 39 Frontend Configuration remote sssessssssss 144 Parameters iii hire i nie iaa 62 G Gain Tracking IEEE 802 11a g OFDM 48 Gain imbalance nnnoseeenenninainaeneeeiniitntnnsrneerennrrnnne 14 17 hcec 203 Group delay Result display 5 treo ttr eren 29 Trace data Guard interval Displayed Length PPDUS 101 107 164 165 H High pass filter Remote RF input Hysteresis Lower Auto level Trigger Upper Auto level l UO data Export file binary data description 238 Export file parameter description EXPOMING ME 72 114 Exporting remote 2 esterna 220 Importing Importing remote Maximum bandwidth eene 230 Sample rate apetito tede das 230 UO measurements Configuring remote sess 141 UO offset Limit check result remote Limits remote ado eebe dete coetu 180 UO Power Trigger softkey aint naia 87 Trigger level remote sessssesssss 155 IEEE 802 11a Signal processing dech one ide eter 45 IEEE 802 11a g OFDM Literature heec retten hte trc tede 52 Modulation formats sssseseeeeeee 60 IEEE 802 119 OFDM Signal eeler ne WEE 45 IEEE 802 11n Modulation formats sse 60 IF Power
42. channel bandwidths are supported For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display CBW column see Signal Field on page 35 Auto same The channel bandwidth of the first valid PPDU is detected and subse type as first quent PPDUs are analyzed only if they have the same channel band PPDU Aist width Auto individu All PPDUs are analyzed regardless of their channel bandwidth ally for each PPDU Al Meas only Only PPDUs with the specified channel bandwidth are analyzed signal M Demod all All PPDUs are assumed to have the specified channel bandwidth as sig nal D Remote command SENSe BANDwidth CHANnel AUTO TYPE on page 166 MCS Index to use Defines the PPDUS taking part in the analysis depending on their Modulation and Coding Scheme MCS index Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display MCS column see Signal Field on page 35 Auto same All PPDUs using the MCS index identical to the first recognized PPDU type as first are analyzed PPDU A1st Auto individ All PPDUs are analyzed ually for each PPDU Al Meas only the Only PPDUs with the MCS index specified for the MCS Index setting
43. fa compensation estimation of gain frequency time c BE Dm cw Ge 2 SZ EE e o Fig 4 1 Block diagram for the R amp S FSW WLAN application using the IEEE 802 11a or g OFDM stand ard In the lower part of the figure the subsequent digital signal processing is shown Packet search and timing detection In the first block the packet search is performed This block detects the Jong symbol LS and recovers the timing The coarse timing is detected first This search is implemented in the time domain The algorithm is based on cyclic repetition within the LS after N 64 samples Numerous treatises exist on this subject e g 1 to 3 User Manual 1173 9357 02 06 46 R amp SS9FSW K91 Measurement Basics Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM Furthermore a coarse estimate A coarse of the Rx Tx frequency offset Af is derived from the metric in 6 The hat generally indicates an estimate e g x is the estimate of x This can easily be understood because the phase of r i lt A r i N is determined by the frequency offset As the frequency deviation Af can exceed half a bin distance between neighboring sub carriers the preceding short symbol SS is also analyzed in order to detect the ambiguity After the coarse timing calculation the time estimate is improved by the fine timing cal culation This is achieved by first estimating the coarse frequency response A4S where k
44. from the signal field LSIGnal IEEE811 02 ac Determines the length of the L signal from the signal field Manual operation See Source of Payload Length IEEE 802 11 AC N on page 109 CONFigure WLAN PVERror MRANge Range This remote control command queries whether the Peak Vector Error results are calcu lated over the complete PPDU or just over the PSDU This command is supported for 802 11b and 802 11g DSSS only E N User Manual 1173 9357 02 06 173 R amp SS9FSW K91 Remote Commands for WLAN Measurements a Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Return values lt Range gt ALL PSDU ALL Peak Vector Error results are calculated over the complete PPDU PSDU Peak Vector Error results are calculated over the PSDU only Usage Query only Manual operation See Peak Vector Error Meas Range IEEE 802 11 B G DSSS on page 110 SENSe BURSt COUNt Value If the statistic count is enabled see SENSe BURSt COUNt STATe on page 174 the specified number of PPDUs is taken into consideration for the statistical evaluation max imally the number of PPDUs detected in the current capture buffer If disabled all detected PPDUS in the current capture buffer are considered Parameters Value RST 1 Example SENS BURS COUN STAT ON Wei ENS BURS COUN 10 Manual operation See PPDU Statistic Count No of PPDUs to Analyze on page 109
45. lt SumBit gt STATus QUEStionable PTRansition lt SumBit gt STATus QUEStionable ACPLimit PTRansition lt SumBit gt lt ChannelName gt STATus QUEStionable LIMit lt n gt PTRansition lt SumBit gt lt ChannelName gt STATus QUEStionable SYNC PTRansition lt BitDefinition gt lt ChannelName gt These commands control the Positive TRansition part of a register Setting a bit causes a 0 to 1 transition in the corresponding bit of the associated register The transition also writes a 1 into the associated bit of the corresponding EVEN register Parameters lt BitDefinition gt Range 0 to 65535 lt ChannelName gt String containing the name of the channel The parameter is optional If you omit it the command works for the currently active channel Commands for Compatibility The following commands are provided only for compatibility to remote control programs from WLAN applications on previous signal analyzers For new remote control programs use the specified alternative commands The CONF BURS lt ResultType gt IMM commands used in former R amp S Signal and Spectrum Analyzers to change the result display are still supported for compatibility rea sons however they have been replaced by the LAY ADD WIND commands in the R amp S FSW see chapter 9 7 Configuring the Result Display on page 184 Note that the CONF BURS lt ResultType gt IMM commands change the screen layout to display the Magnitude Capture buffer in windo
46. must be estimated and compensated from the pilots Therefore this symbol wise phase tracking is activated as the default setting of the R amp S FSW WLAN application see Phase Track ing on page 92 Furthermore the timing drift in FFT is given by ERREUR RA N User Manual 1173 9357 02 06 48 R amp SS9FSW K91 Measurement Basics Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM phase 2gx AN I Nx xkxl Timing drift 4 3 with amp the relative clock deviation of the reference oscillator Normally a symbol wise timing jitter is negligible and thus not modeled in Timing drift However there may be situations where the timing drift has to be taken into account This is illustrated by an example In accordance to 6 the allowed clock deviation of the DUT is up to max 20 ppm Furthermore a long packet with 400 symbols is assumed The result of FFT and Timing drift is that the phase drift of the highest sub carrier k 26 in the last symbol nof symbols is 93 degrees Even in the noise free case this would lead to symbol errors The example shows that it is actually necessary to estimate and compensate the clock deviation which is accomplished in the next block Referring to the IEEE 802 11a g OFDM measurement standard 6 the timing drift phase nin9 is not part of the requirements Therefore the time tracking is not activated as the default setting of the R amp S FSW WLAN application
47. on page 109 SENSe DEMod FORMat BANalyze DBYTes MAX lt NumDataBytes gt If the SENSe DEMod FORMat BANalyze DBYTes EQUal command is set to false this command specifies the maximum number of data bytes allowed for a PPDU to take part in measurement analysis If the SENSe DEMod FORMat BANalyze DBYTes EQUal command is set to true then this command has no effect Parameters lt NumDataBytes gt RST 64 Default unit bytes Manual operation See Min Max Payload Length IEEE 802 11b g DSSS on page 110 SENSe DEMod FORMat BANalyze DBYTes MIN lt NumDataBytes gt For IEEE 802 11b and g DSSS signals only If the SENSe DEMod FORMat BANalyze DBYTes EQUal command is set to true then this command specifies the exact number of data bytes a PPDU must have to take part in measurement analysis If the SENSe DEMod FORMat BANalyze DBYTes EQUal command is set to false this command specifies the minimum number of data bytes required for a PPDU to take part in measurement analysis Parameters lt NumDataBytes gt RST 1 Default unit bytes Manual operation See Min Max Payload Length IEEE 802 11b g DSSS on page 110 SENSe DEMod FORMat BANalyze DURation EQUal lt State gt For IEEE 802 11b and g DSSS signals only ERREUR RA M User Manual 1173 9357 02 06 175 R amp SS9FSW K91 Remote Commands for WLAN Measurements
48. single sweeps See also INI Tiate CONTinuous on page 194 User Manual 1173 9357 02 06 207 R amp SS9FSW K91 Remote Commands for WLAN Measurements mm H H snrse Retrieving Results Query parameters Measurement ACPower MCACpower ACLR measurements also known as adjacent channel power or multicarrier adjacent channel measurements Returns the power for every active transmission and adjacent channel The order is power of the transmission channels power of adjacent channel lower upper power of alternate channels lower upper MSR ACLR results For MSR ACLR measurements the order of the returned results is slightly different power of the transmission channels total power of the transmission channels for each subblock power of adjacent channels lower upper power of alternate channels lower upper power of gap channels lower1 upper1 lower2 upper2 The unit of the return values depends on the scaling of the y axis logarithmic scaling returns the power in the current unit linear scaling returns the power in W CN Carrier to noise measurements Returns the C N ratio in dB CNO Carrier to noise measurements Returns the C N ratio referenced to a 1 Hz bandwidth in dBm Hz CPOWer Channel power measurements Returns the channel power The unit of the return values depends on the scaling of the y axis logarithmi
49. the numeric suffix lt k gt specifies the limit line according to table 9 9 To get a valid result you have to perform a complete measurement with synchronization to the end of the measurement before reading out the result This is only possible for single sweeps See also INIT Tiate CONTinuous on page 194 Return values lt Result gt 0 PASS 1 FAIL Example INIT WAI Starts a new sweep and waits for its end CALC LIM3 FAIL Queries the result of the check for limit line 3 Usage SCPI confirmed Manual operation See Spectrum Emission Mask on page 40 Table 9 9 Limit line suffix lt k gt for WLAN application Suffix Limit 1 to2 These indexes are not used 3 Limit line for Spectrum Emission Mask as defined by ETSI 4 Spectrum Flatness Upper limit line 5 Spectrum Flatness Lower limit line 6 Limit line for Spectrum Emission Mask as defined by IEEE 7 PVT Rising Edge max limit 8 PVT Rising Edge mean limit 9 PVT Falling Edge max limit 10 PVT Falling Edge mean limit CALCulate MARKer FUNCtion POWer RESult lt Measurement gt This command queries the results of power measurements This command is only available for measurements on RF data see chapter 3 2 Fre quency Sweep Measurements on page 39 To get a valid result you have to perform a complete measurement with synchronization to the end of the measurement before reading out the result This is only possible for
50. 0 dB OFF Example INP EATT AUTO OFF INP EATT 10 dB Manual operation See Using Electronic Attenuation Option B25 on page 81 INPut EATT AUTO lt State gt This command turns automatic selection of the electronic attenuation on and off If on electronic attenuation reduces the mechanical attenuation whenever possible This command is only available with option R amp S FSW B25 It is not available if R amp S FSW B17 is active Parameters lt State gt ON OFF 0 1 RST 1 Example INP EATT AUTO OFF Manual operation See Using Electronic Attenuation Option B25 on page 81 INPut EATT STATe lt State gt This command turns the electronic attenuator on and off This command is only available with option R amp S FSW B25 It is not available if R amp S FSW B17 is active ERREUR E N User Manual 1173 9357 02 06 149 R amp S9FSW K91 Remote Commands for WLAN Measurements RAEMETAC C a a a Pau Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters State Example Manual operation ON OFF RST OFF INP EATT STAT ON Switches the electronic attenuator into the signal path See Using Electronic Attenuation Option B25 on page 81 INPut GAIN VALue Gain This command selects the preamplification level if the preamplifier is activated INP GAIN STAT ON see INP
51. 92 Fliasg Tr OR a T E 92 Timing Error Tracking RR E 92 Level Error Gain TAKN Oiana SEENEN 93 PUO TOE TACNE E E 93 Channel Estimation Range Specifies the signal range used to estimate the channels This function is not available for IEEE 802 11b or g DSSS Preamble The channel estimation is performed in the preamble as required in the standard Payload The channel estimation is performed in the preamble and the payload The EVM results can be calculated more accurately Remote command SENSe DEMod CESTimation on page 161 Phase Tracking Activates or deactivates the compensation for phase drifts If activated the measurement results are compensated for phase drifts on a per symbol basis Remote command SENSe TRACking PHASe on page 162 Timing Error Tracking Activates or deactivates the compensation for timing drift If activated the measurement results are compensated for timing error on a per symbol basis Remote command SENSe TRACking TIME on page 163 User Manual 1173 9357 02 06 92 R amp S9FSW K91 Configuration 5 3 8 5 3 8 1 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Level Error Gain Tracking Activates or deactivates the compensation for level drifts within a single PPDU If acti vated the measurement results are compensated for level error on a per symbol basis Remote command SENSe TRACking LEVel on page 162 Pil
52. 94 SENSe DEMod FORMat MCSindex Index This command specifies the MCS index which controls the data rate modulation and streams for IEEE 802 11n ac standards only see document IEEE 802 11n D11 0 June 2009 This command is required if SENSe DEMod FORMat MCSindex MODE is set to MEAS Or DEM Parameters Index RST 1 Example SENS DEM FORM MCS MODE MEAS SENS DEM FORM MCS 1 Manual operation See MCS Index on page 99 SENSe DEMod FORMat MCSindex MODE Mode This command defines the PPDUs taking part in the analysis depending on their Modu lation and Coding Scheme MCS index for IEEE 802 11n ac standards only User Manual 1173 9357 02 06 170 R amp SS9FSW K91 Remote Commands for WLAN Measurements PREGA CC IAMC a nP Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters Mode FBURst ALL MEASure DEMod FBURst The MCS index of the first PPDU is detected and subsequent PPDUs are analyzed only if they have the same MCS index cor responds to Auto same type as first PPDU ALL All recognized PPDUs are analyzed according to their individual MCS indexes corresponds to Auto individually for each PPDU MEASure Only PPDUs with an MCS index which matches that specified by SENSe DEMod FO
53. BURSt SPECtrum OBWidth IMMediate This remote control command configures the result display in window 2 to be ACPR adjacent channel power relative Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See Occupied Bandwidth on page 41 CONFigure BURSt STATistics C CDF IMMediate This remote control command configures the result display in window 2 to be CCDF conditional cumulative distribution function Results are only displayed after a mea surement is executed e g using the INITiate IMMediate command Usage Event Manual operation See CCDF on page 42 ERREUR E N User Manual 1173 9357 02 06 140 R amp SS9FSW K91 Remote Commands for WLAN Measurements Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance 9 5 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance The following commands are required to configure the WLAN IQ measurement described in chapter 3 1 WLAN I Q Measurement Modulation Accuracy Flatness and Toler ance on page 13 Signal leegen 141 e Configuring the Data Input and Oultptut eene 142 Frontend Configuration uere ei A ere xe ee 144 EE Signa EPI Em 151 e Synchronization and OFDM Demodulation eese 160 Tracking and Channel ESUITlatigri uincere re detectar rn ere 161 WE QUI c
54. CONFigure BURSt SPECtrum OBWidth IMMediate on page 140 Querying results CALC MARK FUNC POW RES OBW see CALCulate MARKer FUNCtion POWer RESult on page 207 CCDF The CCDF complementary cumulative distribution function measurement determines the distribution of the signal amplitudes The measurement captures a user definable amount of samples and calculates their mean power As a result the probability that a sample s power is higher than the calculated mean power x dB is displayed The crest factor is displayed in the Result Summary For details see chapter 5 4 4 CCDF on page 118 Ref Level 0 50 dBm AnBW 40 MHz Att 9d8 Meas Time 12 5 ms 1 CCDF CF 100 0 MHz Mean Pwr 20 00 dB 2 Result Summary Samples 500000 Mean 1 0 1 0 01 ea Peak Uu 7 22 dBm 3 34 dBm Fig 3 16 CCDF measurement results Remote command CONFigure BURSt STATistics CCDF IMMediate on page 140 Querying results CALCulate lt n gt MARKer lt m gt Y on page 221 CALCulate STATistics RESult t on page 209 Evaluation Methods for Frequency Sweep Measurements The evaluation methods for frequency sweep measurements in the R amp S FSW WLAN application are identical to those in the R amp S FSW base unit Spectrum application eet 2 pert hte dit ed Rt re Oe ba res Rae rat ss 43 ici SUMMAI ETE I lan dda apitded abelian 43 Lid m M MEER 43 Marker LTE EE 44 EE User Manual 11
55. Fast ACLR mode The main measurement menus for the frequency sweep measurements are identical to the Spectrum application 5 4 2 Spectrum Emission Mask The Spectrum Emission Mask measurement shows the quality of the measured signal by comparing the power values in the frequency range near the carrier against a spectral mask that is defined by the WLAN 802 11 specifications The limits depend on the selected power class Thus the performance of the DUT can be tested and the emissions and their distance to the limit are identified o Note that the WLAN standard does not distinguish between spurious and spectral emis sions The Result Summary contains a peak list with the values for the largest spectral emis sions including their frequency and power The WLAN application performs the SEM measurement as in the Spectrum application with the following settings Table 5 3 Predefined settings for WLAN SEM measurements Setting Default value Number of ranges 3 Frequency Span 12 75 MHz ERREUR E LSS User Manual 1173 9357 02 06 116 R amp S FSW K91 Configuration Frequency Sweep Measurements Setting Default value Fast SEM OFF Sweep time 140 us RBW 30 kHz Power reference type Channel Power Tx Bandwidth 3 84 MHz Number of power classes 1 ually using the Standard Files softkey in the main SEMask menu The subdirectory displayed in the SEM standard file selection dia
56. Fig 3 9 PLCP Header result display for IEEE 802 11b g DSSS standards The following information is provided The signal field information is provided as a decoded bit sequence and where appro priate also in human readable form beneath the bit sequence for each PPDU Table 3 4 Demodulation results in PLCP Header result display IEEE 802 11b g DSSS Result Description Example PPDU Number of the decoded PPDU PPDU 1 A colored block indicates that the PPDU was successfully decoded Signal Information in signal field 01101110 The decoded data rate is shown below 11 MBits s L ob o9o 0 V e Q0A AEELO OOG O OGGG ZI User Manual 1173 9357 02 06 30 R amp S FSW K91 Measurements and Result Displays a_a A Q NA M _ WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Result Description Example Service Information in service field 00100000 Symbol clock state lt Modulation format Length extension bit Lock CCK state gt where Symbol clock state Locked Modulation format see table 4 1 Length extension bit state 1 set not set PSDU Length Information in length field 0000000001 11100 Time required to transmit the PSDU 0 120 us CRC Information in CRC field 111010011100111 Result of cyclic redundancy code check O
57. For signals with a frequency of approximately 4 GHz upwards the harmonics are sup pressed sufficiently by the YIG filter Parameters State ON OFF RST OFF Usage SCPI confirmed Manual operation See High Pass Filter 1 3 GHz on page 74 INPut FILTer YIG STATe State This command turns the YIG preselector on and off Note the special conditions and restrictions for the YIG filter described in YIG Preselec tor on page 74 Parameters State ON OFF 0 1 RST 1 0 for UO Analyzer GSM VSA and MC Group Delay measurements Example INP FILT YIG OFF Deactivates the YIG preselector Manual operation See YIG Preselector on page 74 INPut IMPedance Impedance This command selects the nominal input impedance of the RF input 75 Q should be selected if the 50 Q input impedance is transformed to a higher impedance using a matching pad of the RAZ type 25 O in series to the input impedance of the instrument The power loss correction value in this case is 1 76 dB 10 log 750 500 Parameters Impedance 50 75 RST 500 Example INP IMP 75 Usage SCPI confirmed Manual operation See Impedance on page 74 See Reference Level Settings on page 79 See Unit on page 80 INPut SELect Source This command selects the signal source for measurements i e it defines which connec tor is used to input data to the R amp S FSW If no additional options are installed only RF input is sup
58. Measurement Modulation Accuracy Flatness and Tolerance Parameters lt NumDataSymbols gt RST 1 Example SENS DEM FORM BAN SYMB EQU ON SENS DEMO FORM BANA SYMB MIN Manual operation See Min Max No of Data Symbols IEEE 802 11a g OFDM ac n on page 109 Limits The following commands are required to define the limits against which the individual parameter results are checked Principally the limits are defined in the WLAN 802 11 standards However you can change the limits for your own test cases and reset the limits to the standard values later Note that changing limits is currently only possible via remote control not manually via the user interface The commands required to retrieve the limit check results are described in chap ter 9 9 1 3 Limit Check Results on page 203 Useful commands for defining limits described elsewhere e UNIT EVM on page 203 UNIT GIMBalance on page 203 Remote commands exclusive to defining limits CAL CURIE LINI CITT EE 178 CAL Culatel IMC BURG EVM ALL TAVERaoel nennen 179 CALCulate LIMIEBURSEEVM ALL MAXIImutm see erani ee aeo n aaa ooa aka eda aka deae ado nda 179 CAL Culatel IMC BURG EVM DATA AVERaoel esee 179 CALOulate LIMit BURSt EVM DATA MAXimuUm s eese eere 179 CAL Culatel IMC BURG EVM PI ot AVtEhRagoel esee nennen 179 CALECulate EIMIEBURSEENVMEPIEOEM ADXIEI ees 252m eara cocum ra stato cag a nna Ee erra rata avena in
59. PPDU 1 GD4 1 GD rem Analyzed PPDU 2 GD A GD saag Analyzed PPDU N GDy GDy T 9 9 4 8 Power vs Time Full Burst All complete PPDUS within the capture time are analyzed in three master PPDUs The three master PPDUs relate to the minimum maximum and average values across all complete PPDUS This data is returned in dBm values on a per sample basis Each sam ple relates to an analysis of each corresponding sample within each processed PPDU The type of PVT data returned is determined by the TRACE number passed as an argu ment to the SCPI command TRACE1 minimum PPDU data values TRACE2 mean PPDU data values TRACE3 maximum PPDU data values Supported data formats see FORMat DATA on page 210 ASCii REAL 9 9 4 9 Signal Field The bits are returned as read from the corresponding signal field parts in transmit order Le the first transmitted bit has the highest significance and the last transmitted bit has the lowest significance See also Signal Field on page 35 The TRAC DATA command returns the information as read from the signal field for each analyzed PPDU The signal field bit sequence is converted to an equivalent sequence of hexadecimal digits for each analyzed PPDU in transmit order 9 9 4 10 Spectrum Flatness The spectrum flatness evaluation returns absolute power values per carrier Two trace types are provided for this evaluation User Manual 1173 9357 02 0
60. PPDU Length on page 109 SENSe DEMod FORMat BANalyze SYMBols MAX lt NumDataSymbols gt For IEEE 802 11a g OFDM ac n signals only If the SENSe DEMod FORMat BANalyze SYMBols EQUal command is set to false this command specifies the maximum number of payload symbols allowed for a PPDU to take part in measurement analysis The number of payload symbols is defined as the uncoded bits including service and tail bits Ifthe SENSe DEMod FORMat BANalyze SYMBols EQUal command has been set to true then this command has no effect Parameters lt NumDataSymbols gt RST 64 SENSe DEMod FORMat BANalyze SYMBols MIN lt NumDataSymbols gt For IEEE 802 11a g OFDM ac n signals only Ifthe SENSe DEMod FORMat BANalyze SYMBols EQUal command has been set to true then this command specifies the exact number of payload symbols a PPDU must have to take part in measurement analysis Ifthe SENSe DEMod FORMat BANalyze SYMBols EQUal command is set to false this command specifies the minimum number of payload symbols required for a PPDU to take part in measurement analysis The number of payload symbols is defined as the uncoded bits including service and tail bits ERREUR RA I T i e e e 1 L LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL LLULLLLUI LS User Manual 1173 9357 02 06 177 R amp S FSW K91 Remote Commands for WLAN Measurements 9 5 9 Configuring the WLAN IQ
61. Returns the x values for trace 1 in window 3 Usage Query only TRACe IQ DATA MEMory lt OffsetSamp gt lt NumSamples gt Returns all the UO trace data in the capture buffer The result values are scaled in Volts The command returns a comma separated list of the measured voltage values in floating point format Comma Separated Values CSV The number of values returned is 2 the number of complex samples the first half being the values the second half the Q values The total number of complex samples is displayed in the channel bar in manual operation and can be calculated as lt SampleRate gt lt CaptureTime gt See TRACe IQ SRATe on page 152 and SENSe SWEep TIME on page 152 Parameters lt OffsetSamp gt Offset of the values to be read related to the start of the capture buffer Range 0 to lt NumSamples gt 1 lt NumSamples gt Number of measurement values to be read Range 1 to lt NumSamples gt lt OffsetSa gt RST RST value 9 9 4 Measurement Results for TRACe lt n gt DATA TRACE lt n gt The evaluation method selected by the LAY ADD WIND command also affects the results of the trace data query see TRACe lt n gt DATA TRACE lt n gt Details on the returned trace data depending on the evaluation method are provided here User Manual 1173 9357 02 06 212 Retrieving Results No trace data is available for the following evaluation methods e Magnitude Capture e Result
62. S Signal and Spectrum analyzers this command configured both the guard interval type and the channel bandwidth On the R amp S FSW this command only configures the guard type The channel bandwidth of the PPDU to be measured must be configured separately using the SENSe BANDwidth CHANnel AUTO TYPE com mand Parameters Type Example Manual operation FBURst The Gurad interval length of the first PPDU is detected and sub sequent PPDUs are analyzed only if they have the same length corresponds to Auto same type as first PPDU ALL All PPDUs are analyzed regardless of their guard length corre sponds to Auto individually for each PPDU MS Only PPDUs with short guard interval length are analyzed corresponds to Meas only Short in manual operation MN8 MN16 parameters in previous R amp S Signal and Spectrum Ana lyzers ML Only PPDUs with long guard interval length are analyzed corresponds to Meas only Long in manual operation ML16 ML32 parameters in previous R amp S Signal and Spectrum Ana lyzers DS All PPDUs are demodulated assuming short guard interval length corresponds to Demod all as short in manual operation DN8 DN16 parameters in previous R amp S Signal and Spectrum Ana lyzers DL All PPDUs are demodulated assuming long guard interval length corresponds to Demod all as long in manual operation DL16 DL32 parameters in previous R amp S Signal and Spectrum Ana lyze
63. SENSe BURSt COUNt STATe State If the statistic count is enabled the specified number of PPDUs is taken into consideration for the statistical evaluation maximally the number of PPDUs detected in the current capture buffer If disabled all detected PPDUS in the current capture buffer are considered Parameters State ON OFF RST OFF Example SENS BURS COUN STAT ON SENS BURS COUN 10 Manual operation See PPDU Statistic Count No of PPDUs to Analyze on page 109 SENSe DEMod FORMat BANalyze DBYTes EQUal State For IEEE 802 11b and g DSSS signals only If enabled only PPDUs with a specific payload length are considered for measurement analysis User Manual 1173 9357 02 06 174 R amp SS9FSW K91 Remote Commands for WLAN Measurements PENA CI m Hn r Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance If disabled only PPDUs whose length is within a specified range are considered The payload length is specified by the SENSe DEMod FORMat BANalyze DBYTes MIN command A payload length range is defined as a minimum and maximum number of symbols the payload may contain see SENSe DEMod FORMat BANalyze DBYTes MAX on page 175 and SENSe DEMod FORMat BANalyze DBYTes MIN Parameters State ON OFF RST OFF Manual operation See Equal PPDU Length
64. Summary Global Detailed As opposed to the R amp S FSW base unit the window suffix lt n gt is not considered in the R amp S FSW WLAN application Use the DISPlay WINDow lt n gt SELect to select the window before you query trace results For details on the graphical results of these evaluation methods see chapter 3 1 2 Evaluation Methods for WLAN IQ Measurements on page 21 The following table provides an overview of the main characteristics of the WLAN OFDM symbol structure in the frequency domain for various standards The description of the TRACe results refers to these values to simplify the description Remote Commands for WLAN Measurements R amp S9FSW K91 Retrieving Results 96 ZZ uonenbe Z OZ ue L za oer rzogd 3331 9 S6 zc uonenbe Z OZ ue L za oer rzogd 3331 s p6 ZZ uonenbe Z OZ uo1ew L za er Lzogd 3331 p 6S 0Z uonenbe zL0z L1 z08 PIS 3331 sJeuueoqns jyolld 0L 0L zz uonoes ZLOZ YEW L za oer L zogd 3331 Z sJeuueoqns jolld 0L LL 0z uonoes zLOZ LLz08 PIS 3331 4 214 Sjuejs uoo pejejeJ Buiur 3 zz 9142 L ZLOZ UE L za er Lzogd 3331 LL LLL lot El vl les SZ LL LL SZ eg 9 90L E Ov Sjuejs u09 pejejaJ Buiuui G 7Z jqeL ZLOZ YEW L za er i Z08d 3331 H ZS 0 L ER CALS 42 23 D E v9 0c L Sjuejsuoo p ej 1 Burwu 9 0z age Gel ZLOZ L1 209 PIS dal LL LLL b O L El vil ES SZ LL LL se eS 9 90L E O
65. This command writes the captured UO data to a file The file extension is iq tar By default the contents of the file are in 32 bit floating point format Parameters 1 lt FileName gt String containing the path and name of the target file Example MMEM STOR IQ STAT 1 C R_S Instr user data igq tar Stores the captured UO data to the specified file EEUU N User Manual 1173 9357 02 06 220 R amp SS9FSW K91 Remote Commands for WLAN Measurements Analysis Manual operation See Export on page 114 See IQ Export on page 114 9 10 Analysis The following commands define general result analysis settings concerning the traces and markers in standard WLAN measurements Currently only one Clear Write trace and one marker are available for standard WLAN measurements Analysis for RF measurements General result analysis settings concerning the trace markers lines etc are identical to the analysis functions in the Spectrum application except for some special marker func tions and spectrograms which are not available in the WLAN application For details see the General Measurement Analysis and Display chapter in the R amp S FSW User Manual VT EE 221 e Zooming into the Helene REESEN ENEE EENS SEENEN eg 222 9 10 1 Markers Markers help you analyze your measurement results by determining particular values in the diagram Currently only 1 marker per window can be configured for standard WLAN measur
66. _ the observation length L _ the filter length Af v the variation parameters of the frequency offset Ad the variation parameters of the phase offset oF Og the variation parameters of the IQ offset h i the coefficients of the transmitter filter 4 2 2 Calculation of Signal Parameters The frequency offset the phase offset and the IQ offset are estimated jointly with the coefficients of the transmit filter to increase the estimation quality Once the transmit filter is known all other unknown signal parameters are estimated with a maximum likelihood based estimation which minimizes the cost function N 1 Se 2 _ sf iA atm am L Yirlv xe lev x eI _ gixsi v Ba x Salv Ago x Salv 0 j a v 0 Cost function for signal parameters 4 10 where g go the variation parameters of the gain used in the I Q branch Aga the crosstalk factor of the Q branch into the I branch S v SQ V the filtered reference signal of the I Q branch The unknown signal parameters are estimated in a joint estimation process to increase the accuracy of the estimates User Manual 1173 9357 02 06 55 R amp SS9FSW K91 Measurement Basics Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS The accurate estimates of the frequency offset the gain imbalance the quadrature error and the normalized UO offset are displayed by the measurement software Gain imbalance UO offset quadrature
67. a w HUP Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance If enabled only PPDUs with a specific duration are considered for measurement analy sis If disabled only PPDUs whose duration is within a specified range are considered The duration is specified by the SENSe DEMod FORMat BANalyze DURation MIN command A duration range is defined as a minimum and maximum duration the PPDU may have see SENSe DEMod FORMat BANalyze DURation MAX and SENSe DEMod FORMat BANalyze DURation MIN Parameters State ON OFF RST OFF Manual operation See Equal PPDU Length on page 109 SENSe DEMod FORMat BANalyze DURation MAX lt Duration gt For IEEE 802 11b and g DSSS signals only If the SENSe DEMod FORMat BANalyze DURation EQUal command is set to false this command specifies the maximum number of symbols allowed for a PPDU to take part in measurement analysis If the SENSe DEMod FORMat BANalyze DURation EQUal command is set to true then this command has no effect Parameters lt Duration gt RST 5464 Default unit us Manual operation See Min Max Payload Length IEEE 802 11b g DSSS on page 110 SENSe DEMod FORMat BANalyze DURation MIN lt Duration gt For IEEE 802 11b and g DSSS signals only If the SENSe DEMod FORMat BANaly
68. a reference board revision 3 14 or higher User Manual 1173 9357 02 06 230 R amp S9FSW K91 Annex Reference Sample Rate and Maximum Usable UO Bandwidth for RF Input Max usable Required B option Required U option s Q BW 80 MHz B80 U28 U40 U80 or B28 U40 U80 or B40 U80 160 MHz B160 U28 U40 U80 U160 or B28 U40 U80 U160 or B40 U80 U160 or B80 U160 320 MHz B320 U28 U40 U80 U160 U320 or B28 U40 U80 U160 U320 or B40 U80 U160 U320 or B80 U160 U320 or B160 U320 The bandwidth extension option R amp S FSW B320 U320 requires a reference board revision 3 14 or higher As a rule the usable UO bandwidth is proportional to the output sample rate Yet when the UO bandwidth reaches the bandwidth of the analog IF filter at very high output sample rates the curve breaks Relationship between sample rate and usable UO bandwidth Up to the maximum bandwidth the following rule applies Usable LO bandwidth 0 8 Output sample rate The figure 1 1 shows the maximum usable UO bandwidths depending on the output sample rates R amp S FSW without additional bandwidth extension options sample rate 100 Hz 10 GHz maximum UO bandwidth 10 MHz Sample rate Maximum UO bandwidth 100 Hz to 10 MHz proportional up to maximum 10 MHz 10 MHz to 10 GHz 10 MHz R amp S FSW with options B28 or U28 I Q Bandwidth Extension sample rate 100 Hz 10 GHz maximum bandwidth 28 MHz
69. be one of the following e complex Complex number in cartesian format i e and Q values interleaved and Q are unitless real Real number unitless polar Complex number in polar format i e magnitude unitless and phase rad values interleaved Requires DataType float32 or float64 DataType Specifies the binary format used for samples in the UO data binary file see DataFilename element and chapter A 2 2 I Q Data Binary File on page 238 The following data types are allowed int8 8 bit signed integer data int16 16 bit signed integer data int32 32 bit signed integer data 10at32 32 bit floating point data IEEE 754 float 4 64 bit floating point data IEEE 754 User Manual 1173 9357 02 06 236 R amp S FSW K91 Annex Reference UO Data File Format iq tar Element ScalingFactor Description Optional describes how the binary data can be transformed into values in the unit Volt The binary UO data itself has no unit To get an UO sample in the unit Volt the saved samples have to be multiplied by the value ofthe ScalingFactor For polar data only the magnitude value has to be multiplied For multi channel signals the ScalingFactor must be applied to all channels The attribute unit must be set to v The ScalingFactor must be gt 0 If the ScalingFactor element is not defined a value of 1 V is assumed NumberOfChan nels Optional specifies the number of channels
70. browsers that have JavaScript enabled and if the XSLT stylesheet open IqTar xml file in web browser xslt is available Example ScalingFactor Data stored as int16 and a desired full scale voltage of 1 V ScalingFactor 1 V maximum int16 value 1 V 215 3 0517578125e 5 V Scaling Factor Numerical value Numerical value x ScalingFactor Minimum negative int16 value 215 32768 1V Maximum positive int16 value 215 1 32767 0 999969482421875 V Example PreviewData in XML lt PreviewData gt lt ArrayOfChannel length 1 gt lt Channel gt lt PowerVsTime gt lt Min gt User Manual 1173 9357 02 06 237 UO Data File Format iq tar ArrayOfFloat length 256 gt lt float gt 134 lt float gt lt float gt 142 lt float gt lt float gt 140 lt float gt lt ArrayOfFloat gt lt Min gt lt Max gt lt ArrayOfFloat length 256 gt lt float gt 70 lt float gt lt float gt 71 lt float gt float 69 float ArrayOfFloat Max lt PowerVsTime gt lt Spectrum gt lt Min gt ArrayOfFloat length 256 gt lt float gt 133 lt float gt lt float gt 111 lt float gt lt float gt 111 lt float gt lt ArrayOfFloat gt lt Min gt lt Max gt lt ArrayOfFloat length 256 gt lt float gt 67 lt float gt float 69 float float 70 float lt float gt 69 lt float gt lt ArrayOfFloat gt lt Max gt lt Spec
71. channel type and lt ChannelName gt channel name see table 9 3 Tip to change the channel name use the INSTrument REName command eee User Manual 1173 9357 02 06 133 R amp S9FSW K91 Remote Commands for WLAN Measurements Activating WLAN Measurements Example INST LIST Result for 3 measurement channels ADEM Analog Demod IQ IQ Analyzer SANALYZER Spectrum Usage Query only Table 9 3 Available measurement channel types and default channel names Application lt ChannelType gt Parameter Default Channel Name Spectrum SANALYZER Spectrum UO Analyzer IQ IQ Analyzer Pulse R amp S FSW K6 PULSE Pulse Analog Demodulation ADEM Analog Demod R amp S FSW K7 GSM R amp S FSW K10 GSM GSM Multi Carrier Group Delay MCGD MC Group Delay R amp S FSW K17 Noise R amp S FSW K30 NOISE Noise Phase Noise R amp S FSW PNOISE Phase Noise K40 VSA R amp S FSW K70 DDEM VSA 3GPP FDD BTS BWCD 3G FDD BTS R amp S FSW K72 3GPP FDD UE R amp S FSW MWCD 3G FDD UE K73 TD SCDMA BTS BTDS TD SCDMA BTS R amp S FSW K76 TD SCDMA UE R amp S FSW MTDS TD SCDMA UE K77 cdma2000 BTS R amp S FSW BC2K CDMA2000 BTS K82 cdma2000 MS R amp S FSW MC2K CDMA2000 MS K83 1xEV DO BTS R amp S FSW BDO 1xEV DO BTS K84 1xEV DO MS R amp S FSW MDO 1xEV DO MS K85 WLAN R amp S FSW K91 WLAN WLAN LTE R amp S FSW K10x LTE LTE Real
72. command can be executed the Sequencer must be activated see SYSTem SEQuencer on page 196 Example SYST SEQ ON Activates the Sequencer INIT SEQ MODE SING Sets single sequence mode so each active measurement will be performed once INIT SEQ IMM Starts the sequential measurements Usage Event Manual operation See Sequencer State on page 67 INITiate SEQuencer MODE lt Mode gt This command selects the way the R amp S FSW application performs measurements sequentially T User Manual 1173 9357 02 06 195 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG MM D U M g engi Starting a Measurement Before this command can be executed the Sequencer must be activated see SYSTem SEQuencer on page 196 A detailed programming example is provided in the Operating Modes chapter in the R amp S FSW User Manual Note In order to synchronize to the end of a sequential measurement using OPC OPC or WAI you must use SING1e Sequence mode For details on synchronization see the Remote Basics chapter in the R amp S FSW User Manual Parameters Mode SINGIe Each measurement is performed once regardless of the chan nel s sweep mode considering each channels sweep count until all measurements in all active channels have been performed CONTinuous The measurements in each active channel ar
73. display IEEE 802 11n Parameter Description Format PPDU format used for measurement Not part of the IEEE 802 11n signal field displayed for convenience see PPDU Format to measure on page 94 MCS Modulation and Coding Scheme MCS index of the PPDU as defined in IEEE Std 802 11 2012 section 20 6 Parameters for HT MCSs CBW Channel bandwidth to measure 0 20 MHz or 40 MHz upper lower 1 40 MHz HT SIG Length Sym Human readable length of payload in OFDM symbols The number of octets of data in the PSDU in the range of 0 to 65 535 T User Manual 1173 9357 02 06 36 R amp S FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Parameter Description SNRA Smoothing Not Sounding Reserved Aggregation Smoothing 1 channel estimate smoothing is recommended 0 only per carrier independent unsmoothed channel estimate is recommended Not Sounding 1 PPDU is not a sounding PPDU 0 PPDU is a sounding PPDU Reserved Set to 1 Aggregation 1 PPDU in the data portion of the packet contains an AMPDU 0 otherwise STBC Space Time Block Coding 00 no STBC NSTS NSS 0 the difference between the number of spacetime streams NSTS and the number of spatial streams NSS indicated by the MCS Gl Guard interval length PPDU must have to be measured 1 short GI used after HT training 0 otherwise Ness Number of extension spatial stream
74. dy 0 Referring to FFT the log likelihood function L must be calculated as a function of the trial parameters AF est and Z The tilde generally describes a trial parameter Example x is the trial parameter of X EEUU RE N User Manual 1173 9357 02 06 49 R amp SS9FSW K91 Measurement Basics Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM nof symbols 2 L Af KR gt l 1 k 21 7 7 21 timing 5 common LS J phase phase Kya XH xe with phase 2nxN NxAf T xl phase InxN Nx xkxl Log likelihood function step 1 4 4 The trial parameters leading to the minimum of the log likelihood function are used as estimates AF est and In Log likelihood function step 1 the known pilot symbols au are read from a table In the second step the log likelihood function is calculated for every symbol as a function of the trial parameters 8 and d E 5 common timin g u LS J phase phase ni au Xg xH xe L amp d7 K k 21 7 7 21 with phase 255 x N Nx AF T xl dy phase 9 225g x N Nx amp xkxl Log likelihood function step 2 4 5 Finally the trial parameters leading to the minimum of the log likelihood function are used as estimates and 97 This robust algorithm works well even at low signal to noise ratios with the Cramer Rao Bound being reached Compensation After estimation o
75. e A H n M Retrieving Results CAL Culatel IM BURG lOOFtse AVtChRaoelREGut n 205 CALOulate LIMit BURSt IQOFfset MAXimum RESUIt esses eese 205 CALCulate LIMit BURSt SYMBolerror AVERage RESUuIt 0 c ecceeeeeeeeeeeeeeeaeaeaeaeeneeeees 205 CALCulate LIMit BURSt SYMBolerror MAXimMUM RESUIt 0ccccecccseeeeeceseueseeeeseaesseeesaness 205 CALCulate LIMit BURSt ALL RESult This command returns the result of the EVM limit check for all carriers The limit value is defined by the standard or the user see CALCulate LIMit BURSt ALL on page 178 Return values lt LimitCheck gt PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only CALCulate LIMit BURSt EVM ALL AVERage RESuIt CALCulate LIMit BURSt EVM ALL MAXimum RESult This command returns the result of the average or maximum EVM limit check The limit value is defined by the standard or the user see CALCulate LIMit BURSt EVM ALL MAXimum on page 179 Return values LimitCheck PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only CALCulate LIMit BURSt EVM DATA AVERage RESult CALCulate LIMit BURSt EVM DATA MAXimum RESult This command returns the result of the average or maximum EVM
76. e g of a MIMO signal contained in the I Q data binary file For multi channels the UO samples of the channels are expected to be interleaved within the UO data file see chapter A 2 2 I Q Data Binary File on page 238 If the NumberOfChannels element is not defined one channel is assumed DataFilename Contains the filename of the UO data binary file that is part of the iq tar file It is recommended that the filename uses the following convention lt xyz gt lt Format gt lt Channels gt ch lt Type gt e xyz a valid Windows file name e Format complex polar or real see Format element e Channels Number of channels see NumberOfChannels element e Type float32 float64 int8 int16 int32 or int64 see DataType element Examples e xyz complex 1ch float32 e xyz polar 1ch float64 e xyzreal 1ch int16 e xyz complex 16ch int8 UserData Optional contains user application or device specific XML data which is not part of the iq tar specification This element can be used to store additional information e g the hardware configuration User data must be valid XML content PreviewData Optional contains further XML elements that provide a preview of the I Q data The preview data is determined by the routine that saves an iq tar file e g R amp S FSW For the definition of this element refer to the RsIqTar xsd schema Note that the preview can be only displayed by current web
77. ee EE 194 EINEN T aaa aa a ra Aaa aaia 194 Niate SEQUence e EE 195 INITlate GEOuencer IMMediate anaiai anaE aana 195 INITiate SEQUu neer MODE EE 195 SYSTem o QIRBBI ciat nak een 196 ABORt This command aborts a current measurement and resets the trigger system To prevent overlapping execution of the subsequent command before the measurement has been aborted successfully use the OPC or WAI command after ABOR and before the next command For details see the Remote Basics chapter in the R amp S FSW User Manual To abort a sequence of measurements by the Sequencer use the INI Tiate SEQuencer ABORt on page 195 command Note on blocked remote control programs If a sequential command cannot be completed for example because a triggered sweep never receives a trigger the remote control program will never finish and the remote channel GPIB LAN or other interface to the R amp S FSW is blocked for further commands In this case you must interrupt processing on the remote channel first in order to abort the measurement To do so send a Device Clear command from the control instrument to the R amp S FSW on a parallel channel to clear all currently active remote channels Depending on the used interface and protocol send the following commands e Visa viClear e GPIB ibcir e RSIB RSDLLibclr User Manual 1173 9357 02 06 193 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG MM D
78. error The gain imbalance is the quotient of the estimates of the gain factor of the Q branch the crosstalk factor and the gain factor of the I branch Ja t Ada Gain imbalance 9g Gain imbalance 4 11 The quadrature error is a measure for the crosstalk of the Q branch into the I branch Quadrature Error ARG go jx Aga Quadrature error crosstalk 4 12 The normalized UO offset is defined as the magnitude of the UO offset normalized by the magnitude of the reference signal 0 Wi 0 Oo D pe een lee At this point of the signal processing all unknown signal parameters such as timing offset frequency offset phase offset UO offset and gain imbalance have been evaluated and the measurement signal can be corrected accordingly IQ Offset IO offset 4 13 Error vector magnitude EVM R amp S FSW method Using the corrected measurement signal r v and the estimated reference signal vk the modulation quality parameters can be calculated The mean error vector magnitude EVM is the quotient of the root mean square values of the error signal power and the reference signal power ua EVM IEN Whereas the symbol error vector magnitude is the momentan error signal magnitude normalized by the root mean square value of the reference signal power Mean error vector magnitude EVM 4 14 User Manual 1173 9357 02 06 56 R amp SS9FSW K91 Measurement Basics
79. in the summary bit If a bit is 1 in the enable register and its associated event bit transitions to true a positive transition will occur in the summary bit reported to the next higher level Parameters lt BitDefinition gt Range 0 to 65535 lt ChannelName gt String containing the name of the channel The parameter is optional If you omit it the command works for the currently active channel Controlling the Negative Transition Part STATus OPERation NTRansition lt SumBit gt STATus QUEStionable NTRansition lt SumBit gt STATus QUEStionable ACPLimit NTRansition lt SumBit gt lt ChannelName gt STATus QUEStionable LIMit lt n gt NTRansition lt SumBit gt lt ChannelName gt STATus QUEStionable SYNC NTRansition lt BitDefinition gt lt ChannelName gt This command controls the Negative TRansition part of a register Setting a bit causes a 1 to 0 transition in the corresponding bit of the associated register The transition also writes a 1 into the associated bit of the corresponding EVEN register Parameters lt BitDefinition gt Range 0 to 65535 EE User Manual 1173 9357 02 06 227 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 11 2 6 9 12 Commands for Compatibility lt ChannelName gt String containing the name of the channel The parameter is optional If you omit it the command works for the currently active channel Controlling the Positive Transition Part STATus OPERation PTRansition
80. is defined by a parameter To replace an existing window use the LAYout WINDow lt n gt REPLace command This command is always used as a query so that you immediately obtain the name of the new window as a result Parameters Direction LEFT RIGHt ABOVe BELow lt WindowType gt Type of measurement window you want to add See LAYout ADD WINDow on page 186 for a list of available window types Return values lt NewWindowName gt When adding a new window the command returns its name by default the same as its number as a result User Manual 1173 9357 02 06 190 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 7 3 Configuring the Result Display Example LAY WIND1 ADD LEFT MTAB Result 2 Adds a new window named 2 with a marker table to the left of window 1 Usage Query only LAYout WINDow lt n gt IDENtify This command queries the name of a particular display window indicated by the lt n gt suffix Note to query the index of a particular window use the LAYout IDENtify WINDow command Return values lt WindowName gt String containing the name of a window In the default state the name of the window is its index Usage Query only LAY out WINDow lt n gt REMove This command removes the window specified by the suffix lt n gt from the display The result of this command is identical to the LAYout REMove WINDow command Usage Event
81. logical filter i e are not to be included in analysis are dismissed An appropriate message is provided The corresponding PPDU in the capture buffer is not highlighted The numeric trace results for this evaluation method are described in chapter 9 9 4 9 Signal Field on page 219 Remote command LAY ADD 1 RIGH SFI see LAYout ADD WINDow on page 186 or CONFigure BURSt STATistics SFIeld IMMediate on page 139 Spectrum Flatness The Spectrum Flatness trace is derived from the magnitude of the estimated channel transfer function Since this estimated channel is calculated from all payload symbols of the PPDU it represents a carrier wise mean gain of the channel Assuming that we have a cable connection between the DUT and the R amp S FSW that adds no residual channel distortion the Spectrum Flatness shows the spectral distortion caused by the DUT for example the transmit filter This result display is not available for single carrier measurements IEEE 802 11b g DSSS The diagram shows the absolute power per carrier All 57 carriers are displayed including the unused carrier 0 In contrast to the SISO measurements in previous R amp S signal and spectrum analyzers the trace is no longer normalized to 0 dB scaled by the mean gain of all carriers 2 Spectrum Flatness Carrier 250 50 1 Carrier Carrier 250 The numeric trace results for this evaluation method are described in chapter 9 9 4 10 Spectrum Fl
82. lt WindowName gt string Name of the window In the default state the name of the window is its index Windowlndex numeric value Index of the window Example LAY CAT Result 2 p2p ll Two windows are displayed named 2 at the top or left and 1 at the bottom or right Usage Query only LAYout IDENtify WINDow lt WindowName gt This command queries the index of a particular display window Note to query the name of a particular window use the LAYout WINDow lt n gt IDENtify query Query parameters lt WindowName gt String containing the name of a window Return values lt WindowIndex gt Index number of the window Usage Query only LAYout REMove WINDow lt WindowName gt This command removes a window from the display Parameters lt WindowName gt String containing the name of the window In the default state the name of the window is its index Usage Event eee User Manual 1173 9357 02 06 188 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG MM D U E MMI n J QA U Qa pa Jo Configuring the Result Display LAYout REPLace WINDow WindowName WindowType This command replaces the window type for example from Diagram to Result Sum mary of an already existing window while keeping its position index and window name To add a new window use the LAYout ADD WINDow com
83. noise level or a smaller bandwidth filter than the UO measurement provides and must be deter mined in separate measurements see chapter 3 2 Frequency Sweep Measure ments on page 39 e Modulation Accuracy Flatness and Tolerance Parameters 13 e Evaluation Methods for WLAN IQ Meaeurements 21 3 1 14 Modulation Accuracy Flatness and Tolerance Parameters The default WLAN UO measurement Modulation Accuracy Flatness captures the l Q data from the WLAN signal and determines all the following I Q parameters in a single Sweep User Manual 1173 9357 02 06 13 R amp S9FSW K91 pem P H Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Table 3 1 WLAN I Q parameters for IEEE 802 11a g OFDM ac n Parameter Description Sample Rate Fs Input sample rate PPDU Type of analyzed PPDUs MCS Index Modulation and Coding Scheme MCS index of the analyzed PPDUs GI Guard interval length for current measurement Standard Selected WLAN measurement standard Meas Setup Number of Transmitter Tx and Receiver Rx channels used in the measure ment Capture time Duration of signal capture No of Samples Number of samples captured No of Data Symbols The minimum and maximum number of data symbols that a PPDU may have if itis t
84. on page 95 SENSe DEMod FORMat BANalyze Format Specifies which PSDUs are to be analyzed depending on their modulation Only PSDUs using the selected modulation are considered in result analysis Note to analyze all PPDUs that are identical to the first detected PPDU corresponds to Auto same type as first PPDU use the command SENS DEMO FORM BANA BTYP AUTO TYPE FBUR To analyze all PPDUs regardless of their format and modulation corresponds to Auto individually for each PPDU use the command SENS DEMO FORM BANA BTYP AUTO TYPE ALL Tj See SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 Parameters Format RST QAM64 Example SENS DEMO FORM BAN BPSK6 Manual operation See PPDU Format to measure on page 94 See PSDU Modulation to use on page 95 See PSDU Modulation on page 96 See PPDU Format to measure PSDU Modulation to use on page 102 See PPDU Format on page 103 Table 9 4 Modulation format parameters for IEEE 802 11a or g OFDM standard SCPI parameter Dialog parameter BPSK6 BPSK 1 2 BPSK9 BPSK 3 4 QPSK12 QPSK 1 2 QPSK18 QPSK 3 4 QAM1624 16 QAM 1 2 QAM1636 16 QAM 3 4 QAM6448 64 QAM 2 3 QAM6454 64 QAM 3 4 Table 9 5 Modulation format parameters for IEEE 802 11b or g DSSS standard SCPI parameter Dialog parameter CCK11 Complementary Code Keying at 11 Mbps CCK
85. only Note Providing trigger signals as output is described in detail in the R amp S FSW User Manual Input The signal at the connector is used as an external trigger source by the R amp S FSW No further trigger parameters are available for the connec tor T User Manual 1173 9357 02 06 89 R amp S9FSW K91 Configuration 5 3 6 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Output The R amp S FSW sends a trigger signal to the output connector to be used by connected devices Further trigger parameters are available for the connector Remote command OUTPut TRIGger lt port gt LEVel on page 158 OUTPut TRIGger port DIRection on page 158 Output Type Trigger 2 3 Type of signal to be sent to the output Device Trig Default Sends a trigger when the R amp S FSW triggers gered Trigger Sends a high level trigger when the R amp S FSW is in Ready for trig Armed ger state This state is indicated by a status bit in the STATus OPERation reg ister bit 5 as well as by a low level signal at the AUX port pin 9 User Defined Sends a trigger when user selects Send Trigger button In this case further parameters are available for the output signal Remote command OUTPut TRIGger lt port gt OTYPe on page 159 Level Output Type lt Trigger 2 3 Defines whether a constant high 1 or low 0 signal is sent to the output connector Remote command OUTPut TRIGger l
86. power normalized by the averaged reference power N 1 N 1 Kat n m X ref n Yen EVM n 0 n 0 2 N 1 N 1 3 ls n Ye Ok n 0 n 0 Before calculation of the EVM tracking errors in the measured signal are compensated for if specified by the user In the ideal reference signal the tracking errors are always compensated for Tracking errors include phase center frequency error common phase error timing sampling frequency error and gain errors quadrature offset and gain imbalance errors however are not corrected The PPDU EVM is not part of the IEEE standard and no limit check is specified Never theless this commonly used EVM calculation can provide some insight in modulation quality and enables comparisons to other modulation standards LE User Manual 1173 9357 02 06 20 R amp S FSW K91 Measurements and Result Displays REESEN WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Fig 3 6 I Q diagram for EVM calculation Peak Vector Error IEEE method The peak vector error Peak EVM is defined in section 18 4 7 8 Transmit modulation accuracy of the IEEE 802 11b standard The phase timing and gain tracking errors of the measurement signal center frequency error common phase error sampling fre quency error are compensated for before EVM calculation The standard does not specify a normalization factor for the error vector magnitude To get an EVM value that is independ
87. see Timing Error Tracking on page 92 The time tracking option should rather be seen as a powerful analyzing option In addition the tracking of the gain g in FFT is supported for each symbol in relation to the reference gain g 1 at the time instant of the long symbol LS At this time the coarse channel transfer function H9 is calculated This makes sense since the sequence rx is compensated by the coarse channel transfer function H S before estimating the symbols Consequently a potential change of the gain at the symbol caused for example by the increase of the DUT amplifier temper ature may lead to symbol errors especially for a large symbol alphabet M of the MQAM transmission In this case the estimation and the subsequent compensation of the gain are useful Referring to the IEEE 802 11a g OFDM measurement standard 6 the compensation of the gain g is not part of the requirements Therefore the gain tracking is not activated as the default setting of the R amp S FSW WLAN application see Level Error Gain Track ing on page 93 Determining the error parameters log likelihood function How can the parameters above be calculated In this application the optimum maximum likelihood algorithm is used In the first estimation step the symbol independent param eters A fres and amp are estimated The symbol dependent parameters can be neglected in this step i e the parameters are set to g 1 and
88. short DS Demod allas All PPDUs are demodulated assuming long guard interval length long DL Remote command CONFigure WLAN GTIMe AUTO on page 164 CONFigure WLAN GTIMe AUTO TYPE on page 164 CONFigure WLAN GTIMe SELect on page 165 5 3 9 Evaluation Range The evaluation range defines which objects the result displays are based on Evaluation Range AE EE DE GEET 9 g Statistics PPDU Statistic Count No of PPDU s to Analyze Time Domain Source of Payload Length Equal PPDU Length Max Payload Length 66000 us bytes PVT Peak Vector Error IEEE Meas Range Fig 5 5 Evaluation range settings for IEEE 802 11b and g DSSS standards User Manual 1173 9357 02 06 108 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance PPDU Statistic Count No of PPDUs to Anahyze 109 Source of Payload Length IEEE 802 11 AC NK eame 109 Equal RRE e Lt EE 109 Min Max No of Data Symbols IEEE 802 11a g OFDM ac n 109 Min Max Payload Length IEEE 802 115 g DSSS 1 neret 110 PVT Average Length IEEE 802 11b g DSSS ssec nnda 110 PVT Reference Power IEEE 802 11b g D9S99 ee eterne 110 Peak Vector Error Meas Range IEEE 802 11 B G DSSS 110 PPDU Statistic Count No of PPDUs to Analyze If the statistic count is enabled the spe
89. so that the pilot sequence detected in the signal is used instead of the sequence defined by the standard However if the pilot sequence generated by the DUT is correct it is recommended that you use the According to Standard setting because it generates more accurate mea surement results 8 2 Error Messages and Warnings The following messages are displayed in the status bar in case of errors Results contribute to overall results despite inconsistencies Info Comparison between HT SIG Payload Length and Estimated Payload Length not performed due to insufficient SNR The R amp S FSW K91 application compares the HT SIG length against the length estimated from the PPDU power profile If the two values do not match the corresponding entry is highlighted orange If the signal quality is very bad this comparison is suppressed and the message above is shown Warning HT SIG of PPDU was not evaluated Decoding of the HT SIG was not possible because there was to not enough data in the Capture Memory potential PPDU truncation Warning Mismatch between HT SIG and estimated SNR Power PPDU length The HT SIG length and the length estimated by the R amp S FSW application from the PPDU power profile are different User Manual 1173 9357 02 06 124 R amp S FSW K91 Optimizing and Troubleshooting the Measurement aS aS a ee Error Messages and Warnings Warning Physical Channel estimation impossible Phy Chan results
90. step step 2 5 f necessary adapt the settings as described for the individual measurements in the R amp S FSW User Manual 6 Select the Display Config button and select the evaluation methods that are of interest to you Arrange them on the display to suit your preferences 7 Exit the SmartGrid mode and select the Overview softkey to display the Over view again 8 Selectthe Analysis button in the Overview to make use of the advanced analysis functions in the result displays e Configure a trace to display the average over a series of sweeps if necessary increase the Sweep Count in the Sweep settings ERREUR RU a User Manual 1173 9357 02 06 121 How to Determine the OBW SEM ACLR or CCDF for WLAN Signals e Configure markers and delta markers to determine deviations and offsets within the evaluated signal e Use special marker functions to calculate noise or a peak list e Configure a limit check to detect excessive deviations 9 Optionally export the trace data of the graphical evaluation results to a file a In the Traces tab of the Analysis dialog box switch to the Trace Export tab b Select Export Trace to ASCII File c Define a file name and storage location and select OK R amp S FSW K91 Optimizing and Troubleshooting the Measurement Optimizing the Measurement Results 8 Optimizing and Troubleshooting the Mea surement e Optimizing the Measurement Results 123 Er
91. ul Bt 92 163 Trigger Configuration remote ssssesssss 152 Configuration softkey sss 84 Default P e Drop out Lu BropsOUt TIME risasi nanas External remote ae Ss as Le 0 REC ek Level Measurements sse OUI M E E Offset softkey Trigger level 7p Auto ummEEE External trigger remote VQ Power remote rennen IF Power remote sssssssseenee RF Power remote z Tigger SOUE oroare ann E ai eE a iena External Free Run Si lied Mec Pm IF POWO sees geed Erd ee TEE EA le 87 TIME T 87 Troubleshooting 123 Input overload 142 U Units EVM results ssss eee Gain imbalance results Reference level ssseesss sss Upper Level Hysteresis SOTO streets sS m DL LM 112 Usable UO bandwidth Definition eeessssssss essere 230 User manuals s es kanoni iea Eii 6 User sample rate Definition essssssssse esee 230 W Windows Adding remote Closing remote Configuring Layout remote Maximizing remote sene 185 Querying remote 188 Replacing remote 189 Splitting remote 185 Types remote 186 Window title bar 11 WLAN Measurements sssssssssssnenenene 13 Measurements step by s
92. 0 40 60 80 100 120 140 160 180 200 EIER 10000 rate fan MHz Fig 1 1 Relationship between maximum usable HO bandwidth and output sample rate with and without bandwidth extensions R amp S FSW with activated option B320 or U320 I Q Bandwidth Extension sample rate 100 Hz 10 GHz maximum bandwidth 320 MHz Sample rate Maximum UO bandwidth 100 Hz to 400 MHz proportional up to maximum 320 MHz 400 MHz to 10 GHz 320 MHz R amp S9 FSW K91 Annex Reference UO Data File Format iq tar Usable UO MHz Activated option B320 U320 Output sample 80 120 160 200 240 280 320 360 400 10000 rate four MHz Fig 1 2 Relationship between maximum usable DO bandwidth and output sample rate for active R amp S FSW B320 A 2 VQ Data File Format iq tar UO data is packed in a file with the extension ig tar An ig tar file contains UO data in binary format together with meta information that describes the nature and the source of data e g the sample rate The objective of the iq tar file format is to separate I Q data from the meta information while still having both inside one file In addition the file format allows you to preview the UO data in a web browser and allows you to include user specific data The iq tar container packs several files into a single tar archive file Files in tar format can be unpacked using standard archive tools see http en wikipedia org wiki Compar ison of file archivers av
93. 11111111 11111111 11111111 11111111 11111111 11111111 01010000 00000100 10000000 10011100 11111111 11111111 11111111 11111111 11111111 00000101 00100000 11001000 01000010 10101011 11111111 11111111 11111111 11111111 11111111 11001111 00000000 01000110 00110000 00001101 00010100 Fig 3 8 Bitstream result display for IEEE 802 11b g DSSS standards The numeric trace results for this evaluation method are described in chapter 9 9 4 1 Bitstream on page 216 Remote command LAY ADD 1 RIGH BITS see LAYout ADD WINDow on page 186 or CONFigure BURSt STATistics BSTReam IMMediate on page 139 Constellation This result display shows the in phase and quadrature phase results for all payload sym bols and all carriers for the analyzed PPDUS of the current capture buffer The Tracking Channel Estimation according to the user settings is applied The inphase results I are displayed on the x axis the quadrature phase Q results on the y axis IESSE User Manual 1173 9357 02 06 24 R amp S FSW K91 Measurements and Result Displays pem M M H WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 2 Constellation The numeric trace results for this evaluation method are described in chapter 9 9 4 3 Constellation on page 216 Remote command LAY ADD 1 RIGH CONS see LAYout
94. 1ni 2 n reri deir dre on ka ER 103 Demodulation IEEE 802 11a g OFDM The following settings are available for demodulation of IEEE 802 11a g OFDM signals T User Manual 1173 9357 02 06 93 R amp S FSW K91 Configuration H WLAN IQ Measurement Modulation Accuracy Flatness Tolerance dm m m Demodulation PPDUs to Analyze PPDU Analysis Mode for each property to analyze Channel Bandwidth to measure PSDU Modulation Coded OFDM Coded OFDM BPSK 1 2 Rate is indicated in Signal Guard Interval Length 16 samples Fig 5 1 Demodulation settings for IEEE 802 11a or g OFDM standard PPDU Analysis Modb 2 iate deed uade niet aia 94 FPDU Format to WIGSSLIFO EE 94 Channel Bandwidth to measure CBDM 95 PSDU Modulation e BEE 95 PSDUMOQOUISOE c caddies ce eg rre ea ve dau cr o eed eet ru dete ever eene 96 PPDU Analysis Mode Defines whether all or only specific PPDUs are to be analyzed Auto same type as first PPDU The signal symbol field i e the PLCP header field of the first recog nized PPDU is analyzed to determine the details of the PPDU All PPDUS identical to the first recognized PPDU are analyzed All subsequent settings are set to Auto mode Auto individually for each PPDU All PPDUs are analyzed User defined User defined settings define which PPDUS are analyzed This setting is automatically selected when any of the subsequent settings are changed to a value oth
95. 2 06 120 R amp S9FSW K91 How to Perform Measurements in the WLAN Application 7 2 How to Determine the OBW SEM ACLR or CCDF for WLAN Signals 11 Select the Display Config button and select the displays that are of interest to you up to 16 Arrange them on the display to suit your preferences 12 Exit the SmartGrid mode 13 Start a new sweep with the defined settings e To perform a single sweep measurement press the RUN SINGLE hardkey e To perform a continuous sweep measurement press the RUN CONT hardkey Measurement results are updated once the measurement has completed How to Determine the OBW SEM ACLR or CCDF for WLAN Signals 1 Press the MODE key on the front panel and select the WLAN application The R amp S FSW opens a new measurement channel for the WLAN application I Q data acquisition is performed by default 2 Select the Signal Description button to define the digital standard to be used 3 Select the required measurement a Press the MEAS key on the front panel b Inthe Select Measurement dialog box select the required measurement The selected measurement is activated with the default settings for WLAN immedi ately 4 For SEM measurements select the required standard settings file a Inthe SEMask menu select the Standard Files softkey b Select the required settings file The subdirectory displayed in the file selection dialog box depends on the standard you selected in
96. 3 R amp S FSW K91 Measurements and Result Displays iS e aa i a 8 Se Frequency Sweep Measurements Marker Peak List The marker peak list determines the frequencies and levels of peaks in the spectrum or time domain How many peaks are displayed can be defined as well as the sort order In addition the detected peaks can be indicated in the diagram The peak list can also be exported to a file for analysis in an external application 2 Marker Peak List No 1 Remote command LAY ADD 1 RIGH PEAK see LAYout ADD WINDow on page 186 Results CALCulate lt n gt MARKer lt m gt X on page 209 CALCulate lt n gt MARKer lt m gt Y on page 221 User Manual 1173 9357 02 06 44 R amp SS9FSW K91 Measurement Basics Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM 4 Measurement Basics Some background knowledge on basic terms and principles used in WLAN measure ments is provided here for a better understanding of the required configuration settings 4 1 Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM This description gives a rough view of the signal processing when using the R amp S FSW WLAN application with the IEEE 802 11a or g OFDM standard Details are disregarded in order to provide a concept overview Abbreviations au symbol at symbol of subcarrier k EVM error vector magnitude of subcarrier k EVM error vector magnitude of current packe
97. 3 9357 02 06 35 R amp S FSW K91 Measurements and Result Displays mE HP Um WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Parameter Description P Parity bit Signal Tail Signal tail preset to 0 Table 3 6 Demodulation parameters and results for Signal Field result display IEEE 802 11ac Parameter Description Format PPDU format used for measurement Not part of the IEEE 802 11ac signal field displayed for convenience see PPDU Format to measure on page 94 MCS Modulation and Coding Scheme MCS index of the PPDU as defined in IEEE Std 802 11 2012 section 20 6 Parameters for HT MCSs BW Channel bandwidth to measure 0 20 MHz 1 40 MHz 2 80 MHz 3 80 80 MHz and 160MHz L SIG Length Sym Human readable length of payload in OFDM symbols STBC Space Time Block Coding 0 no spatial streams of any user has space time block coding 1 all spatial streams of all users have space time block coding GI Guard interval length PPDU must have to be measured 1 short guard interval is used in the Data field 0 short guard interval is not used in the Data field Ness Number of extension spatial streams Ness see Extension Spatial Streams sounding on page 107 CRC Cyclic redundancy code Table 3 7 Demodulation parameters and results for Signal Field result
98. 357 02 06 216 R amp SS9FSW K91 Remote Commands for WLAN Measurements mLECI s Un EBP s Retrieving Results e All Carriers CONFigure BURSt CONStellation CARRier SELect ALL Ns pairs of and Q data per OFDM Symbol OFDM Symbol 1 l4 Q4 H 2 Q12 l1 Nst Q1 nst OFDM Symbol 2 l2 4 Q21 122 Q2 buet Q2 nst OFDM Symbol N Ini Qui Ini Qu 2 In se Qus e Pilots Only CONFigure BURSt CONStellation CARRier SELect PILOTS Nsp pairs of and Q data per OFDM Symbol in the natural number order OFDM Symbol 1 l 4 Q 4 112 Q45 li ven Qu sp OFDM Symbol 2 l2 4 Q4 122 Q25 Iz sp Q2 Nsp OFDM Symbol N Iu Qu In 2 Qu 2 In sp Qu uso e Single carrier 1 pair of and Q data per OFDM Symbol for the selected carrier CONFigure BURSt CONStellation CARRier SELect k with ke t Nusea 1 2 Nused m 1 2 UD Nusea 1 2 OFDM Symbol 1 l 4 Qy4 OFDM Symbol 2 24 Q21 OFDM Symbol N ly 4 Qu 4 9 9 4 4 Constellation vs Carrier This measurement represents the complex constellation points as and Q data See for example IEEE Std 802 11 2012 Fig 18 10 BPSK QPSK 16 QAM and 64 QAM con stellation bit encoding Each and Q point is returned in floating point format Data is returned as a repeating array of interleaved and Q data in groups of Nusea subcarriers per OFDM Sy
99. 36 e Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Toler IGS si vans HX 141 e Configuring Frequency Sweep Measurements on WLAN Signals 184 e Configuring the Result Display 184 ERC ECHT TEE 193 e Retrieving REI 197 ER 0o eS 221 Status Registers C 224 e Commands for Compsibiliby oou antec aed netted oe Eneas 228 9 1 Common Suffixes For the description of the remote commands in the WLAN application the following com mon suffixes are used Table 9 1 Common suffixes for WLAN measurements on I Q data Suffix Value range Description lt n gt 1 16 Window lt k gt 1 8 Limit EEUU UR N User Manual 1173 9357 02 06 126 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 2 9 2 1 Introduction Suffix Value range Description lt t gt 1 Trace lt m gt 1 4 Marker Table 9 2 Common suffixes for frequency sweep measurements Suffix Value range Description n 1 16 Window lt t gt 1 6 Trace lt m gt 1 16 Marker lt ch gt 1 18 Tx channel Channel 1 11 ALTernate or ADJa cent channel lt k gt 1 8 Limit line Introduction Commands are program messages that a controller e g a PC sends to the instrument or software They operate its functions setting commands or events and request infor mation query commands Some commands can on
100. 4 6 FFT Spectrum on page 218 Remote command LAY ADD 1 RIGH FSP see LAYout ADD WINDow on page 186 or CONFigure BURSt SPECtrum FFT IMMediate on page 138 LEES User Manual 1173 9357 02 06 28 R amp S FSW K91 Measurements and Result Displays AMETE mG M WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Group Delay Displays all Group Delay GD values recorded on a per subcarrier basis over the num ber of analyzed PPDUs as defined by the Evaluation Range gt Statistics settings see PPDU Statistic Count No of PPDUs to Analyze on page 109 All 57 carriers are shown including the unused carrier 0 This result display is not available for single carrier measurements IEEE 802 11b g DSSS FGroup Delay 22 Clrw Carrier 250 50 1 Carrier Carrier 250 Group delay is a measure of phase distortion and defined as the derivation of phase over frequency To calculate the group delay the estimated channel is upsampled inactive carriers are interpolated and phases are unwrapped before they are differentiated over the carrier frequencies Thus the group delay indicates the time a pulse in the channel is delayed for each carrier frequency However not the absolute delay is of interest but rather the deviation between carriers Thus the mean delay over all carriers is
101. 43 INPut ATTenuation PROTection RESet This command resets the attenuator and reconnects the RF input with the input mixer after an overload condition occured and the protection mechanism intervened The error status bit bit 3 in the STAT QUES POW status register and the INPUT OVLD message in the status bar are cleared The command works only if the overload condition has been eliminated first For details on the protection mechanism see chapter 4 6 1 RF Input Protection on page 61 Usage Event INPut COUPling lt CouplingType gt This command selects the coupling type of the RF input Parameters lt CouplingType gt AC AC coupling DC DC coupling RST AC Example INP COUP DC Usage SCPI confirmed Manual operation See Input Coupling on page 74 INPut FILTer HPASs STATe lt State gt Activates an additional internal high pass filter for RF input signals from 1 GHz to 3 GHz This filter is used to remove the harmonics of the R amp S FSW in order to measure the harmonics for a DUT for example This function requires option R amp S FSW B13 ERREUR RE I LL SSE User Manual 1173 9357 02 06 142 R amp SS9FSW K91 Remote Commands for WLAN Measurements NAE A CP sm Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Note for RF input signals outside the specified range the high pass filter has no effect
102. 5 Trigger Level Trigger Source Settings Defines the trigger level for the specified trigger source For details on supported trigger levels see the data sheet Remote command TRIGger SEQuence LEVel IFPower on page 155 TRIGger SEQuence LEVel IQPower on page 155 TRIGger SEQuence LEVel EXTernal port on page 154 TRIGger SEQuence LEVel RFPower on page 156 Repetition Interval Trigger Source Settings Defines the repetition interval for a time trigger The shortest interval is 2 ms The repetition interval should be set to the exact pulse period burst length frame length or other repetitive signal characteristic Remote command TRIGger SEQuence TIME RINTerval on page 157 Drop Out Time Trigger Source Settings Defines the time the input signal must stay below the trigger level before triggering again For more information on the drop out time see chapter 4 8 3 Trigger Drop Out Time on page 64 Remote command TRIGger SEQuence DTIMe on page 153 Trigger Offset Trigger Source Settings Defines the time offset between the trigger event and the start of the sweep For more information see chapter 4 8 1 Trigger Offset on page 63 T User Manual 1173 9357 02 06 88 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance offset gt 0 Start of the sweep is delayed offset
103. 55 Complementary Code Keying at 5 5 Mbps DBPSK1 Differential Bl Phase shift keying DQPSK2 Differential Quadrature phase shift keying User Manual 1173 9357 02 06 168 R amp S9FSW K91 Remote Commands for WLAN Measurements REAEMETCACIMO C X Tc P Pe Mr Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SCPI parameter PBCC11 Dialog parameter PBCC at 11 Mbps PBCC22 PBCC at 11 Mbps PBCC55 PBCC at 5 5 Mbps SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE Analysis This remote control command specifies how signals are analyzed Parameters Analysis Example FBURst ALL MMIX MGRF DMIX DGRF MVHT DVHT MNHT DNHT FBURSt The format of the first valid PPDU is detected and subsequent PPDUs are analyzed only if they have the same format corre sponds to Auto same type as first PPDU ALL All PPDUs are analyzed regardless of their format corresponds to Auto individually for each PPDU MNHT Only PPDUs with format Non HT are analyzed IEEE 802 11 a DNHT All PPDUs are assumed to have the PPDU format Non HT IEEE 802 11 a MMIX Only PPDUs with format HT MF Mixed are analyzed IEEE 802 11 n MGRF Only PPDUs with format HT GF Greenfield are analyzed IEEE 802 11 n DMIX All PPDUs are assumed to have the PPDU format HT MF
104. 6 117 R amp S FSW K91 Configuration Frequency Sweep Measurements To restore adapted measurement parameters the following parameters are saved on exiting and are restored on re entering this measurement e Reference level and reference level offset e RBW VBW e Sweep time e Span 5 4 4 CCDF The CCDF measurement determines the distribution of the signal amplitudes comple mentary cumulative distribution function The CCDF and the Crest factor are displayed For the purposes of this measurement a signal section of user definable length is recor ded continuously in zero span and the distribution of the signal amplitudes is evaluated The measurement is useful to determine errors of linear amplifiers The crest factor is defined as the ratio of the peak power and the mean power The Result Summary displays the number of included samples the mean and peak power and the crest factor The CCDF measurement is performed as in the Spectrum application with the following settings Table 5 5 Predefined settings for WLAN CCDF measurements Setting Default value CCDF Active on trace 1 Analysis bandwidth 10 MHz Number of samples 62500 Detector Sample For further details about the CCDF measurements refer to Statistical Measurements in the R amp S FSW User Manual To restore adapted measurement parameters the following parameters are saved on exiting and are restored on re entering this measurement e Re
105. 6 219 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 9 5 Retrieving Results Table 9 14 Query parameter and results for Spectrum Flatness TRACE1 All spectrum flatness values per channel TRACE2 An average spectrum flatness value for each of the 53 or 57 117 within the IEEE 802 11 n standard carriers Absolute power results are returned in dB Supported data formats FORMat DATA ASCiiJREAL Importing and Exporting UO Data and Results The I Q data to be evaluated in the WLAN application can not only be measured by the WLAN application itself it can also be imported to the application provided it has the correct format Furthermore the evaluated UO data from the WLAN application can be exported for further analysis in external applications For details on importing and exporting UO data see the R amp S FSW User Manual MMEMoryMOADNOS TAT Gs M 220 MMEMBryIS TORS IO STATE 0 cs c2 s scseeceeteededenevscgpedadetecemstuagasdenseasteeeteadanteveesuuaeeacbieaes 220 MMEMory LOAD IQ STATe 1 lt FileName gt This command restores UO data from a file The file extension is iqw Parameters lt FileName gt String containing the path and name of the source file Example MMEM LOAD IQ STAT 1 C R_S Instr user data iqw Loads IQ data from the specified file Usage Setting only Manual operation See Import on page 114 See IQ Import on page 114 MMEMory STORe IQ STATe 1 lt FileName gt
106. 70 Short symbol SS IEEE 802 112 g OFDM seem 46 Signal capturing D fatiOn 5 hem tren terrre re eerte Duration remote 2 Remote control ae reto Heil LERA Signal description COMMUTING EE 72 Remote control nentes 141 Softkey Signal field Signal Field PPDU analysis ette 94 97 104 Result display dte text tie ene eet 35 Thrace data oett rr eren 219 Glo WER 80 Signal processing IEEE 802 11a g OFDM nesses 45 IEEE 802 11b g DSSS i nop 52 Signal source PROMOS acs 143 Single Sequencer le 67 Single sweep Eier 113 Slope MI 89 156 SMAMGIG aise cers Aves etae recen eser iren ae 22 68 softkey Average Length K91 91n sussssssss Ref Pow Max Mean K91 91n i Signal Field K91 91n sse Softkeys Amplitude Config eese A to Level rrr Channel defined Sequencer a Continue Single Sweep susssssssss Continuous Sequencer ssesssseeeeeeresesrirrerrrresrenne Continuous Sweep Sg Display Config 2 iren orc mter tent o qr PR External dicm Frequency Contig EE UO Power IF Power IMPON eC Input Source Config x Sech lQ EXpOrt ics eiii rn erro rore enn User Manual 1173 9357 02 06 R amp S9FSW K91 IQ IMPO E E 114 Lower Level Hysteresis 112
107. 73 9357 02 06 42 R amp S FSW K91 Measurements and Result Displays DEET Frequency Sweep Measurements Diagram Displays a basic level vs frequency or level vs time diagram of the measured data to evaluate the results graphically This is the default evaluation method Which data is displayed in the diagram depends on the Trace settings Scaling for the y axis can be configured CF 1 95 GHz 1001 pts 2 57 MHz Span 25 7 MHz Remote command LAY ADD 1 RIGH DIAG see LAYout ADD WINDow on page 186 Result Summary Result summaries provide the results of specific measurement functions in a table for numerical evaluation The contents of the result summary vary depending on the selected measurement function See the description of the individual measurement functions for details 2 Result Summary Channel Bandwidth Power TX1 Ref 1 229 MHz 0 86 dBm 0 86 dBm Bandwidth Lower opper 0 000 kHz 50 00 z 79 59 dB 80 34 dB 00 kHz 85 04 dB 83 85 dB Remote command LAY ADD 1 RIGH RSUM see LAYout ADD WINDow on page 186 Marker Table Displays a table with the current marker values for the active markers Stimulus Response Function T Function Result 13 197 GH 5 87 der mn 1 1705 Remote command LAY ADD 1 RIGH MTAB see LAYout ADD WINDow on page 186 Results CALCulate lt n gt MARKer lt m gt X on page 209 CALCulate lt n gt MARKer lt m gt Y on page 221 LEE User Manual 1173 9357 02 06 4
108. 802 11a g OFDM es AT Reference level sss sse Display aeeiiaii ananena ananta 59 Softkey cre Effective m wa 58 Auto Level Physical iie ede et bedic tide eH ides 58 Auto settings eerte Compatibility Meastime Auto softkey sss R amp S FSQ Meastime Manual softkey Ss R amp S FSV Remote Control Compensating Auto track time IEEE 802 118 g OFDM sse Remote contre 181 Payload window IEEE 802 11a g OFDM Complementary cumulative distribution function B Seg CODE ssc enc nena iR ee 42 Constellation Bandwidth Result display sesssssssseeeseeeeeeenee 24 Extension options sse 230 231 vs carrier result display 225 Maximum usable issiria inrano 230 vs carrier trace data 217 Meri ied vs symbol trace data ssssssssssssssss 216 Relationship to sample rate sssssss 231 Continue single sweep Bit error rate BER lnc 113 Pilot iier teat i ter edet 14 Continuous Sequencer Bitstream ll p C aes 67 Result display eid reete eot dee pesci 22 Continuous sweep Trace datai tr seen tonno i 216 DOMKOY cy 113 User Manual 1173 9357 02 06 247 R amp S9FSW K91 Index Conventions SCPI commands isisisi i aeii 127 Copying Measurement channel remote
109. 9 Magnitude Capture sn Marker table esie sn 43 Peak list tocco rms es 44 PvT Full PPDU 31 Result Summary ET nc 43 Result Summary items 111 Result Summary items remote 192 Result Summary Detailed 2nd Result Summary Global sssseseeseeeeneeereeeerrreerrreerrees 33 User Manual 1173 9357 02 06 251 R amp S9FSW K91 Index see also Evaluation methods 13 Signal Field zt cna eus Spectrum Flatness H WEAN Em Results sup 216 Cor ge M 216 Constellation vs carrier eeeeeeeeese Constellation vs symbol iss E Data format remote sse Evaluating EE EVM vs Carrier seis FET d In a ee iei Ere Group delay 2 irre eet terre t eben Eee Magnitude Capture E Numeric remote sesesssesseseeeee 198 PVT Full Burst eicere ret eerie tenes 219 Result summary zs ss Retrieving remote ssssesssesses 197 RF remote iret cod etti Pete rere etre neget 206 Signal field T E E Spectrum Flatness A 219 Trace remote uie erret trees 210 Trace data query remote ssssussse 212 Result Summary Detailed result display ssssssssssss 32 Evaluation method s Global result display ssseseesesss 33 tems to display
110. A M A H A r s Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters Duration Numeric value in seconds Range 0 001 to 16000 0 RST 0 001 Default unit s Example ADJ CONF DUR MODE MAN Selects manual definition of the measurement length ADJ CONF LEV DUR 5ms Length of the measurement is 5 ms Manual operation See Changing the Automatic Measurement Time Meastime Manual on page 112 SENSe ADJust CONFigure DURation MODE Mode In order to determine the ideal reference level the R amp S FSW performs a measurement on the current input data This command selects the way the R amp S FSW determines the length of the measurement Parameters Mode AUTO The R amp S FSW determines the measurement length automatically according to the current input data MANual The R amp S FSW uses the measurement length defined by SENSe ADJust CONFigure DURation on page 181 RST AUTO Manual operation See Resetting the Automatic Measurement Time Meastime Auto on page 112 See Changing the Automatic Measurement Time Meastime Manual on page 112 SENSe ADJust CONFigure HYSTeresis LOWer Threshold When the reference level is adjusted automatically using the SENSe ADJust LEVel on page 183 command the internal attenuators and the preamplifier are also adjusted In order to avoid frequen
111. ADD WINDow on page 186 or CONFigure BURSt CONSt CSYMbol IMMediate on page 137 Constellation vs Carrier This result display shows the in phase and quadrature phase results for all payload sym bols and all carriers for the analyzed PPDUS of the current capture buffer The Tracking Channel Estimation according to the user settings is applied This result display is not available for single carrier measurements IEEE 802 11b g DSSS The x axis represents the carriers The magnitude of the in phase and quadrature part is shown on the y axis both are displayed as separate traces l trace 1 Q trace 2 SSS SSSR User Manual 1173 9357 02 06 25 R amp S FSW K91 Measurements and Result Displays Sa eS Se WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 4Constellation vs Carrier Carrier 250 50 1 Carrier Carrier 250 The numeric trace results for this evaluation method are described in chapter 9 9 4 4 Constellation vs Carrier on page 217 Remote command LAY ADD 1 RIGH CVC see LAYout ADD WINDow on page 186 or CONFigure BURSt CONSt CCARrier IMMediate on page 137 EVM vs Carrier This result display shows all EVM values recorded on a per subcarrier basis over the number of analyzed PPDUS as defined by the Evaluation Range gt Statistics The Tracking Channel Estimation according to the user settings is applied see chapter 5 3 7 Tracking and Channel Estimation on page 91
112. ANimum nennen nennen nennen nnntr sh nnns inn rins sn hnnn nsn nen nnne 179 CAL Culate IMC DBURGCEVM ALL M Aximum RE Gu 204 CALOulate LIMit BURSt EVM ALL AVERage CALOulate LIMit BURSt EVM ALL AVERage RESUIt essent 204 CAL Culate IM BURGCEVM DATA MANimum nennen nennt srnenn sse n erts sete re nne n nnns nnn 179 CAL Culate IMC DBURGCEVM DATA MAXimum RE Gu 204 CAL Culate IM BURGCEVMDATATAVEhRaoel enne nnnr nennen entr nena 179 CAL Culate IMC DBURGCEVMDATATAVERaoel RE Gu 204 CALOCulate LIMit BURSt EVM PILot MAXimum essen eene nennen nnn rnt n se tenn ns nter nsn 179 CALOCulate LIMit BURSt EVM PILot MAXimum RESUult essent 205 CAL Culate IM BURGCEVMPDIL ol AVERaoel nennen nnne nnns nnn 179 CALCulate LIMit BURSt EVM PILot AVERage RESUIt sess 205 CAL Culate IM DBURGCEERbRorMAvimum nnne nes ennnn nnns nn nennen innen 180 CAL Culate IM BURGCEERRorMANimum RE Gu 205 CAL Culate IM BURGCEERRo AVERaoel nennen nennen nnn nen nenr nne nntn enn 180 CAL Culate IM BURGCEERRo AVERaoeltbRtE Gut 205 CAL Culate IM BURG IOOFfSerMAvimum enne eneneneennnrn net nnr sen rnts innert senten nena 180 CAL Culate IM BURG IOOFfSserMAvimum REGOu nnt 205 CAL Culate IM BURGrClIOOFtSset AVERaoel ener enne rnnnnnn nnn rentre nnn 180 CAL Culate IM BURGCIOOFrset AVERaoelRE Gu 205 CALOulate LIMit BURSt SYMBolerror AVERage sessi 180 CAL Culate IMC BURG S
113. BURSt SPECtrum FFT IMMediate esee 138 CONFioure BURG GbECimum FL ATness GE ec 138 CONFigure BURSt SPECtrum FLATness IMMediate sse ener 138 CONFigure BURSt SPECtrum MASK IMMediate essere 140 CONFigure BURSt SPECtrum OBWidth IMMediate eese 140 CONFigure BURStSTATistics BSTReam IMMediate sess 139 CONFioure BURGCSTATlsttce CGCDElIMMediatel emnes 140 CONFigure BURStSTATistics SFleld IMMediate sess enne 139 CONFigure POWer AUTO esses nennen teet enne nnne nnn enrte tnnt reete tree tse e testes trenes enne n nne nnnnn 147 CONFigure POWer AUTO rinor e ai end ie ER E ed dede te A e CE Dg genae ad eben 181 CONFioure POWer AUTO ZGWEen TIME 181 CONFigure POWer EXPoecl d RE dene ezi eei ra pep ve puede dee eb tease Dee len ede a o re atado 147 CONFigure STANdard CONFioure WAN EN Tenslon AUTO TE 163 CONFigure WLAN GTIMGiIAU TO eraot doter reato ono eta seen err eb sent ere vtta ntu pvo err Eee arbe Eze kn tado 164 CONFioure WAN GTlMe AUTO TE 164 El tt UE Reng dE EE 165 CONFioure WAN PALL oadLENG SR 173 CONFigure WLAN PVERror MRANge 173 CONFigure WLAN STBGC AUTOFTYPE 4 eere tton eere ey seh ipsa VER ENER EUER e dn EE 166 DiAGnosttc GERViceN curce eene n nenre treni enn rnsi eh nrts set nns seat nnns ennt sinn nnns sena Incipe loe
114. Bm to 30 dBm RST 20 dBm Example TRIG LEV Top 30DBM Manual operation See Trigger Source Settings on page 85 See Trigger Level on page 88 TRIGger SEQuence LEVel POWer AUTO lt State gt By default the optimum trigger level for power triggers is automatically measured and determined at the start of each sweep for Modulation Accuracy Flatness Tolerance measurements This function is only considered for TRIG SEQ SOUR IFP and TRIG SEQ SOUR RFP see TRIGger SEQuence SOURce on page 156 In order to define the trigger level manually switch this function off and define the level using TRIGger SEQuence LEVel IFPower on page 155 or TRIGger SEQuence LEVel RFPower on page 156 User Manual 1173 9357 02 06 155 R amp SS9FSW K91 Remote Commands for WLAN Measurements REAEMECACMCUO GA M n Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters for setting and query State OFF Switches the auto level detection function off ON Switches the auto level detection function on RST ON Manual operation See Trigger Source Settings on page 85 See Trigger Level Mode on page 88 TRIGger SEQuence LEVel RFPower lt TriggerLevel gt This command defines the power level the RF input must exceed to cause a trigger event Note that any RF attenuation or preamplifi
115. DATAIAV ERAGE inaani a inia aaa EE pe reu EE De ciRit om ro Eaa Tna 201 FETGHh BURSEEVM DATA MAXIFYUIETI nara p acuu sa ro Saad nu dn nag avian cedars SNE n nana Rv cr anna 201 FEVGIIBURSEEVNEDATACMITNIRUETIG cu ENEE ENNEN 201 FETOHh BURSEEVMEPIEGtAVERagS nieder entere ccce eR EEN 201 FETCH BURSEEVM PIEoEMAXITUIYI EEN 3 e conn RE nan cac sn ases e qe a ia oe hn Ra qur cha ae 201 FETCH BU RSEEVMEPPIEGEMINIERUITI crece reru rra n nara u khe nnn ENNEN 201 EEGENEN 201 FETCh BURSEPERIODUMAXITIUEYTO Seege titer eo e ee ettet ee eehieg 201 a eebe ele d TE KEE 201 FEFCNBURSEGIMBalance EE 201 FETCh BURSEGIMBalance MAXIMUM EE 201 FETChBURSEGIMBalance MINIImulq a cac nuntio rennen ann c ede n neci anai aini nde 201 FETOChBURGCIOOFfSet AVER agoe 202 FELICIHB URSEIQOOFISSEMA XII cci etae peo pedec etr RAA 202 FETCHhIBBURSEIDOPISeEMINIEDENIP 21 01 ENER hinds 202 FEICHBURSEBPAYLOSGO E 202 FEUCIEBURSEDPEBNISA iuis edat eon Ed Ed EE E 202 FETChiBURSEPISESImbDIe ee aggies A ENEE RO cte Pone EAR ESA NEE Ee 202 FETCHBURSEQUADofiset AVERAQe oreet a e RE hrs Ronan audeo eae ade deuda 202 FETCh BURGrOUAfDoftset MAvimum 202 FETCh BURSEQUADOffSeEMINIIUEYI nuu uode aeneus a odes nce ense dE 202 FETCHBURSERMSDAVERGge eege rore cr tree esee ete corte Edge et 202 PE User Manual 1173 9357 02 06 199 R amp SS9FSW K91 Remote Commands for WLAN Measurements PRENNE EM CD m
116. DD 1 RIGH EVCH See LAYout ADD WINDow on page 186 or CONFigure BURSt EVM ECHip IMMediate on page 137 CONFigure BURSt EVM ESYMbol IMMediate on page 137 EVM vs Symbol This result display shows all EVM values calculated on a per carrier basis over the num ber of analyzed PPDUs as defined by the Evaluation Range gt Statistics settings see PPDU Statistic Count No of PPDUs to Analyze on page 109 The Tracking Channel Estimation according to the user settings is applied see chapter 5 3 7 Tracking and Channel Estimation on page 91 The MinHold Maxhold and Average traces are displayed ERREUR RA M User Manual 1173 9357 02 06 27 R amp S FSW K91 Measurements and Result Displays a a Se WLAN UO Measurement Modulation Accuracy Flatness and Tolerance This result display is not available for single carrier measurements IEEE 802 11b g DSSS 2 EVM vs Symbol 1 Mine2 Avg e 3 Ma Symb 1 595 2 Symb Symb 5952 Remote command LAY ADD 1 RIGH EVS see LAYout ADD WINDow on page 186 or CONFigure BURSt EVM ESYMbol IMMediate on page 137 FFT Spectrum This result display shows the power vs frequency values obtained from a FFT The FFT is performed over the complete data in the current capture buffer without any correction or compensation 2 FFT Spectrum 16 0 MHz div The numeric trace results for this evaluation method are described in chapter 9 9
117. Data gt lt PreviewData gt lt PreviewData gt lt RS_IQ TAR FileFormat Element Description RS IQ TAR File Format The root element of the XML file It must contain the attribute ileFormatVersion that contains the number of the file format definition Currently fileFormatVersion 2 is used Name Optional describes the device or application that created the file Comment Optional contains text that further describes the contents of the file DateTime Contains the date and time of the creation of the file Its type is xs dateTime see RsIqTar xsd Samples Contains the number of samples of the UO data For multi channel signals all channels have the same number of samples One sample can be e A complex number represented as a pair of and Q values e Acomplex number represented as a pair of magnitude and phase values e Areal number represented as a single real value See also Format element Clock Contains the clock frequency in Hz i e the sample rate of the UO data A signal gen erator typically outputs the UO data at a rate that equals the clock frequency If the UO data was captured with a signal analyzer the signal analyzer used the clock frequency as the sample rate The attribute unit must be set to Hz Format Specifies how the binary data is saved in the UO data binary file see DataFilename element Every sample must be in the same format The format can
118. EMod FORMat BANalyze S YMBols EQUAal esses 177 SENSe DEMod FORMat BANalyze S YMBols MAX essere nnne 177 SENSe DEMod FORMat BANalyze S YMBols MIN esee 177 User Manual 1173 9357 02 06 172 R amp SS9FSW K91 Remote Commands for WLAN Measurements PRENNE EMEND IA A a Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance CONFigure BURSt PVT AVERage Value Defines the number of samples used to adjust the length of the smoothing filter for PVT measurement This command is only available for IEEE 802 11b g DSSS standards Parameters Value Manual operation See PVT Average Length IEEE 802 11b g DSSS on page 110 CONFigure BURSt PVT RPOWer Mode This remote control command configures the use of either mean or maximum PPDU power as a reference power for the 802 11b g DSSS PVT measurement Parameters Mode MEAN MAXimum Manual operation See PVT Reference Power IEEE 802 11b g DSSS on page 110 CONFigure WLAN PAYLoad LENGth SRC Source Defines which payload length is used to determine the minimum or maximum number of required data symbols IEEE 802 11n ac Parameters Source ESTimate HTSignal ESTimate Uses a length estimated from the input signal HTSignal IEEE811 02 n Determines the length of the HT signal
119. ENt section Query parameters lt ChannelName gt String containing the name of the channel The parameter is optional If you omit it the command works for the currently active channel Usage Query only 9 11 2 3 Reading Out the CONDition Part STATus OPERation CONDition STATus QUEStionable CONDition STATus QUEStionable ACPLimit CONDition lt ChannelName gt ERREUR EA N User Manual 1173 9357 02 06 226 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 11 2 4 9 11 2 5 Status Registers STATus QUEStionable LIMit lt n gt CONDition lt ChannelName gt STATus QUEStionable SYNC CONDition lt ChannelName gt This command reads out the CONDition section of the status register The command does not delete the contents of the EVENt section Query parameters lt ChannelName gt String containing the name of the channel The parameter is optional If you omit it the command works for the currently active channel Usage Query only Controlling the ENABle Part STATus OPERation ENABle lt SumBit gt STATus QUEStionable ENABle lt SumBit gt STATus QUEStionable ACPLimit ENABle lt SumBit gt lt ChannelName gt STATus QUEStionable LIMit lt n gt ENABle lt SumBit gt lt ChannelName gt STATus QUEStionable SYNC ENABle lt BitDefinition gt ChannelName This command controls the ENABle part of a register The ENABle part allows true conditions in the EVENt part of the status register to be reported
120. FEATness SELect ice aiite terr te aa 138 CONFigure BURSt SPECtrum FLATness IMMediate eese 138 CONFioure BURG GTATeticeBGTReamtJMMedatel ne neneoeoresere rer ererorsrnrrre rene 139 CONFloure BURG GTATletice GEledt MMediatel nnne 139 DISPIavEWINBOWwESOPESELSGL nea o tex Peru atu euer neu eene ua ad x eque Re e a Depas 139 E M User Manual 1173 9357 02 06 136 R amp SS9FSW K91 Remote Commands for WLAN Measurements mA P sS ees Selecting a Measurement CONFigure BURSt CONSt CCARrier IMMediate This remote control command configures the result display type of window 2 to be Con stellation vs Carrier Results are only displayed after a measurement is executed e g using the TNTTiate IMMediate command Usage Event Manual operation See Constellation vs Carrier on page 25 CONFigure BURStCONSt CSYMbol IMMediate This remote control command configures the result display type of window 2 to be Con stellation vs Symbol Results are only displayed after a measurement has been exe cuted e g using the INITiate IMMediate command Usage Event Manual operation See Constellation on page 24 CONFigure BURSt EVM ECARrier IMMediate This remote control command configures the result display type of window 2 to be EVM vs Carrier Results are only displ
121. FSW html I User Manual 1173 9357 02 06 6 R amp SS9FSW K91 Preface mm m M Conventions Used in the Documentation Service Manual This manual is available in PDF format on the CD delivered with the instrument It describes how to check compliance with rated specifications instrument function repair troubleshooting and fault elimination It contains all information required for repairing the R amp S FSW by replacing modules Release Notes The release notes describe the installation of the firmware new and modified functions eliminated problems and last minute changes to the documentation The corresponding firmware version is indicated on the title page of the release notes The most recent release notes are also available for download from the R amp S website on the R amp S FSW product page at http www2 rohde schwarz com product FSW html gt Downloads Firmware 1 3 Conventions Used in the Documentation 1 3 4 Typographical Conventions The following text markers are used throughout this documentation Convention Description Graphical user interface ele All names of graphical user interface elements on the screen such as dia ments log boxes menus options buttons and softkeys are enclosed by quota tion marks KEYS Key names are written in capital letters File names commands File n
122. Filter 1 3 GHz Analog YIG Presclector Baseband Input Connector Baseband Input I Radio Fregusncy SEALS pP 74 IFA NE SOONG n 74 impedanco HEP 74 Pugh PASS Filler E E 74 VIG PYOSCIOCIOR ER 74 User Manual 1173 9357 02 06 73 R amp S FSW K91 Configuration LAM A a 8 8 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Radio Frequency State Activates input from the RF INPUT connector Remote command INPut SELect on page 143 Input Coupling The RF input of the R amp S FSW can be coupled by alternating current AC or direct current DC AC coupling blocks any DC voltage from the input signal This is the default setting to prevent damage to the instrument Very low frequencies in the input signal may be dis torted However some specifications require DC coupling In this case you must protect the instrument from damaging DC input voltages manually For details refer to the data sheet Remote command INPut COUPling on page 142 Impedance The reference impedance for the measured levels of the R amp S FSW can be set to 50 O or 75 Q 75 Q should be selected if the 50 Q input impedance is transformed to a higher impedance using a 75 Q adapter of the RAZ type 25 Q in series to the input impedance of the instrument The correction value in this case is 1 76 dB 10 log 750 500 Remote command INPut IMPedance on page 143 High Pass Filter 1 3 GHz Activates an additional internal high
123. Hz 2 2 09494 GHz 39 75 dBm 73 48 dB 22 98 dB 2 09642 GHz 50 91 dBm 84 65 dB 21 15 dB 2 09652 GHz 51 84 dBm 85 57 dB 22 65 dB 2 09739 GHz 52 33 dBm 86 07 dB 34 57 dB 2 10259 GHz 49 37 dBm 83 11 dB 31 61 dB 2 10342 GHz 50 68 dBm 84 42 dB 22 27 dB 2 10373 GHz 51 81 dBm 85 55 dB 22 05 dB 2 10439 GHz 38 64 dBm 72 37 dB 21 87 dB 2 11026 GHz 39 24 dBm 72 97 dB 18 47 dB Fig 3 15 SEM measurement results Remote command on page 140 Querying results on page 207 TRAC DATA LIST see on page 210 Occupied Bandwidth The Occupied Bandwidth OBW measurement determines the bandwidth in which in default settings 99 96 of the total signal power is to be found The percentage of the signal power to be included in the bandwidth measurement can be changed The occupied bandwidth is indicated as the Occ BW function result in the marker table the frequency markers used to determine it are also displayed Ref Level 0 00 dBm gt RBW 20knz Att 10 dB s SWT ims VBW 300kHz Mode Auto FFT M1 1 7 37 dBm 2 0996300 GHz 1001 pts St Span 11 52 MHz 2 Marker Table Type Ref Tree Stimulus Response Function Function Result Mi 1 2 09963 GHz 27 37 dBm 1 1 2 09796 Hz 32 78 m cc Bw 4 166073926 MHz User Manual 1173 9357 02 06 41 R amp S9FSW K91 Measurements and Result Displays 3 2 2 Frequency Sweep Measurements For details see chapter 5 4 3 Occupied Bandwidth on page 117 Remote command
124. IEEE 802 11a g OFDM ac n only EVCarrier EVM vs Carrier IEEE 802 11a g OFDM ac n only EVCHip EVM vs Chip IEEE 802 11b and g DSSS only EVSYmbol EVM vs Symbol IEEE 802 11a g OFDM ac n only FSPectrum FFT Spectrum GDELay Group Delay IEEE 802 11a g OFDM ac n only RSDetailed Result Summary Detailed IEEE 802 11a g OFDM ac n only RSGLobal Result Summary Global SFleld Signal Field IEEE 802 11a g OFDM ac n PLCP Header IEEE 802 11b and g DSSS SFLatness Spectrum Flatness IEEE 802 11a g OFDM ac n only PFPPdu PvT Full PPDU Window types for RF data DIAGram Diagram SEM ACLR MTABle Marker table SEM ACLR User Manual 1173 9357 02 06 187 R amp S9FSW K91 Remote Commands for WLAN Measurements PRENNE EMEND AD AX HJA X mJ n M M Configuring the Result Display Parameter value Window type PEAKIist Marker peak list SEM ACLR RSUMmary Result summary SEM ACLR LAYout CATalog WINDow This command queries the name and index of all active windows from top left to bottom right The result is a comma separated list of values for each window with the syntax lt WindowName_1 gt lt Windowlndex_1 gt lt WindowName_n gt lt Windowlndex_n gt Return values
125. K or Failed 0 OK Remote command LAY ADD 1 RIGH SFI See LAYout ADD WINDow on page 186 or CONFigure BURSt STATistics SFIeld IMMediate on page 139 PvT Full PPDU Displays the minimum average and maximum power vs time diagram for all PPDUs 3 PVT Full PPDU Start 5 0 ps 100 02 ms Stop 165 0 us Fig 3 10 PvT Full PPDU result display for IEEE 802 11a g OFDM ac n standards For single carrier measurements IEEE 802 11b g DSSS the PVT results are dis played as percentage values of the reference power The reference can be set to either the maximum or mean power of the PPDU ERREUR RA U User Manual 1173 9357 02 06 31 R amp S FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 1 PVT Full PPDU ei Mine 2 Avg e 3 Max 94 67 us 941 704545455 ys Fig 3 11 PvT Full PPDU result display for IEEE 802 11b g DSSS standards Remote command LAY ADD WIND 2 RIGH PFPP see WI 7 on page 186 Result Summary Detailed The detailed result summary contains individual measurement results for the Transmitter and Receiver channels and for the bitstream This result display is not available for single carrier measurements IEEE 802 11b g DSSS 3 Result Summary Detailed TX 1 Min gt Limit Limit IQ Off jain Imbalance Limit Limit Limit Limit ation on page 111 However the results are always calcul
126. LAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe TRACking LEVel State Activates or deactivates the compensation for level variations within a single PPDU If activated the measurement results are compensated for level error on a per symbol basis Parameters State ON OFF RST OFF Manual operation See Level Error Gain Tracking on page 93 SENSe TRACking PHASe State Activates or deactivates the compensation for phase drifts If activated the measurement results are compensated for phase drifts on a per symbol basis Parameters State ON OFF 0 1 RST 1 Manual operation See Phase Tracking on page 92 SENSe TRACking PlLots Mode In case tracking is used the used pilot sequence has an effect on the measurement results Parameters Mode STANdard DETected STANdard The pilot sequence is determined according to the corresponding WLAN standard In case the pilot generation algorithm of the device under test DUT has a problem the non standard conform pilot sequence might affect the measurement results or the WLAN application might not synchronize at all onto the signal generated by the DUT DETected The pilot sequence detected in the WLAN signal to be analyzed is used by the WLAN application In case the pilot generation algo rithm of the device under test DUT has a problem the non standard conform pilot sequence will not affect the measurement result
127. LAY out WINDow lt n gt REPLace lt WindowType gt This command changes the window type of an existing window specified by the suffix lt n gt The result of this command is identical to the 1 Avout REPLace WINDow command To add a new window use the LAYout WINDow lt n gt ADD command Parameters lt WindowType gt Type of measurement window you want to replace another one with See LAYout ADD WINDow on page 186 for a list of available window types Selecting Items to Display in Result Summary The following command defines which items are displayed in the Result Summary ERREUR E N User Manual 1173 9357 02 06 191 R amp S9FSW K91 DISPlay WINDow lt n gt TABLe ITEM lt Item gt lt State gt Remote Commands for WLAN Measurements Configuring the Result Display Defines which items are displayed in the Result Summary see Result Summary Detailed on page 32 and Result Summary Global on page 33 Note that the results are always calculated regardless of their visibility in the Result Summary Parameters Item Item to be included in Result Summary For an overview of pos sible results and the required parameters see the tables below State ON OFF ON Item is displayed in Result Summary OFF Item is not displayed in Result Summary RST ON Table 9 7 Parameters for the items of the Result Summary Detailed Result in table SCPI parameter TX channel
128. LLLLLLLLLLLLLLLLLLLLLLLL LLC LLLSIAXS J User Manual 1173 9357 02 06 154 R amp SS9FSW K91 Remote Commands for WLAN Measurements RAM H I r Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Manual operation See Trigger Source Settings on page 85 See Trigger Level on page 88 TRIGger SEQuence LEVel IFPower lt TriggerLevel gt This command defines the power level at the third intermediate frequency that must be exceeded to cause a trigger event Note that any RF attenuation or preamplification is considered when the trigger level is analyzed If defined a reference level offset is also considered For details on the trigger settings see Trigger Source Settings on page 85 Parameters lt TriggerLevel gt For details on available trigger levels and trigger bandwidths see the data sheet RST 10 dBm Example TRIG LEV IFP 30DBM Manual operation See Trigger Source Settings on page 85 See Trigger Level on page 88 TRIGger SEQuence LEVel IQPower lt TriggerLevel gt This command defines the magnitude the I Q data must exceed to cause a trigger event Note that any RF attenuation or preamplification is considered when the trigger level is analyzed For details on the trigger source see Trigger Source Settings on page 85 Parameters lt TriggerLevel gt Range 130 d
129. LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLULLLULLLLLM R User Manual 1173 9357 02 06 81 R amp S9FSW K91 Configuration 5 3 5 5 3 5 1 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance When you switch off electronic attenuation the RF attenuation is automatically set to the same mode auto manual as the electronic attenuation was set to Thus the RF attenu ation may be setto automatic mode and the full attenuation is provided by the mechanical attenuator if possible Both the electronic and the mechanical attenuation can be varied in 1 dB steps Other entries are rounded to the next lower integer value If the defined reference level cannot be set for the given attenuation the reference level is adjusted accordingly and the warning Limit reached is displayed in the status bar Remote command INPut EATT STATe on page 149 INPut EATT AUTO on page 149 INPut EATT on page 149 Input Settings Some input settings affect the measured amplitude of the signal as well The parameters Input Coupling and Impedance are identical to those in the Input settings see chapter 5 3 4 1 Input Source Settings on page 73 Preamplifier option B24 Input Settings If option R amp S FSW B24 is installed a preamplifier can be activated for the RF input signal For R amp S FSW 26 models the input signal is amplified by 30 dB if the preamplifier is activated For R amp S FSW 8 or 13 models the following settings a
130. MINimlrm coros erroe eor eo roo auri ri e EYEX ERU Fe E DE ERU eR E ca HERE ooh 202 FETCh BURSERMS MAYXimUtTi iiii iocis renean rro npe a Exec ae aeree Co ENS eed FE b FEN Ed deu 202 FETGh BURSERMS MINITOUITI s c deerit etr sehr ee a Pra x vex aea eere eee ewe erbe e eus e erae a AR aepo 202 FETOCHBURGSCHRMSTAVERaoel EArt AAEAtE AAE nE EEn Enr Ennen EEn Enen enn 202 FETOCh BURG SGvM olerror AVtEhage eee nnnn enhn rnen etn aa a i aai iaraa Viadana asiaa EA FETCh BURSt SYMBolerror MAXimum FETOCh BURG SG M olerrorMiNimum Ae FETOCh SNvMBoCOUND ie rns rrr snnt sit rn tients its s ennt seres sers rsen sn nureen 198 FORMat DA TA 210 ll Ee ene TMU EE 194 INITiate SEQuencerABOREL E 195 INITiate SEQuencer IMMediate 195 INITlate GEOuencerMODE A 195 ll EE MET 194 Jui TIAS MEE dee 148 INPut AT Tenu ation AU TO incor entrer oret eroe e ee EY TV Tbe EYE ATE VM Cedies 148 INbPutATTenuaton Ph OTectonRE Get 142 INPut COUPling 142 Joli zum ODAS 149 INPUEEATT AUTO ii trente creta eder e n e ied er S Xv e Rd e er ce er EE ERR Re ree 149 lei RER RE 149 lgl a Te el RE A NEE 142 INPut FIETer YIG S TA EE 143 INPut GAIN STATe INPE GAIN VALUE Ji is critt tr i rt e ae ea etre perpe epe tee erre rette eet de e RR Dre ERR INPUEIMP CCA CO sacs D
131. Marker Table on page 43 See Marker Peak List on page 44 9 10 2 Zooming into the Display 9 10 2 1 Using the Single Zoom DISPlay WINDow lt n gt ZOOM AREA DISPlay WINDow lt n gt ZOOM STATe DISPlay WINDow lt n gt ZOOM AREA lt x1 gt lt y1 gt lt x2 gt lt y2 gt This command defines the zoom area To define a zoom area you first have to turn the zoom on 1 Frequency Sweep 1Rm Clr e 1 origin of coordinate system x1 0 y1 0 2 end point of system x2 100 y2 100 3 zoom area e g x1 60 y1 30 x2 80 y2 75 User Manual 1173 9357 02 06 222 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 10 2 2 Analysis Parameters lt x1 gt lt y1 gt Diagram coordinates in of the complete diagram that define the lt x2 gt lt y2 gt Zoom area The lower left corner is the origin of coordinate system The upper right corner is the end point of the system Range 0 to 100 Default unit PCT DISPlay WINDow lt n gt ZOOM STATe lt State gt This command turns the zoom on and off Parameters lt State gt ON OFF RST OFF Example DISP ZOOM ON Activates the zoom mode Using the Multiple Zoom DISPlay WINDow n ZOOM MULTiple zoom AREA cessere 223 DiSblavlfWiNDow nztZOOM ML Tiple zo0omz GTATe n 224 DISPlay WINDow lt n gt ZOOM MULTiple lt zoom gt AREA lt x1 gt lt y1 gt lt x2 gt lt y2 gt This command defines the zoom area f
132. Meastime Auto s Meastime Manual sseee 112 Outputs e EE Power Sensor Preamp icc cuu et re t iH nities Ref Level Offset gue encre Repetition interval Result Config 1 dnce ete erinnern RF Atten Auf iei cierre nnne RF Atten Manual m o RF POWED sur M ET WEE Signal Capture E Signal Description eire ess 72 Single Sequencer s essen 67 Single Sweep Sweep Config Sweep COUNT aita e een e intro ete 113 Time e Trigger et E 84 Trigger Offset iet tente 88 Upper Level Hysteresis 112 Space Time Block Coding H NET 99 106 Space time stream ssesssssseeeeeneenn 58 Span Meng 68 Specifics for Config ralo vive ui terr se Ai irene 71 Spectrum Emission Mask See SEM P 40 Spectrum Flatness Parameters norte Re ne Roe Result display H Trace data eerie rre Standard see Digital standard sss 10 Standard WLAN measurements sees 13 Starting WLAN applicatio 5 rero teretes 9 Statistic Count sis sees eere 109 174 arci e deeg edd Eege 174 Statistics PPDUS 4 erect tives Metab Ase eii intere res oleas 17 Status bat rtt entrer en ret re 12 Error massages cese apetece se ect rio Ferr as 124 Status registers Contents Querying 2 STAT QUES POW irent rris 142 STATus QUEStionable SYNC
133. Mod FORMat BANalyze BTYPe AUTO TYPE MMIX SENSe BANDwidth CHANnel AUTO TYPE MB20 GFM20 IEEE 802 11n Green Field Mode 20 MHz sampling rate For new programs use SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE MGRFE SENSe BANDwidth CHANnel AUTO TYPE MB20 TRIGger SEQuence MODE lt Source gt Defines the trigger source Note that this command is maintained for compatibility reasons only Use the TRIGger SEQuence SOURce on page 156 commands for new remote control pro grams This command configures how triggering is to be performed Parameters lt Source gt IMMediate EXTernal VIDeo RFPower IFPower TV AF AM FM PM AMRelative LXI TIME SLEFt SRIGht SMPX SMONo SSTereo SRDS SPILot BBPower MASK PSENsor TDTRigger IQPower EXT2 EXT3 User Manual 1173 9357 02 06 229 R amp S9FSW K91 Annex Reference Sample Rate and Maximum Usable UO Bandwidth for RF Input A Annex Reference A 1 Sample Rate and Maximum Usable UO Bandwidth for RF Input Definitions e Input sample rate ISR the sample rate of the useful data provided by the connec ted instrument to the R amp S FSW input e User Output Sample rate SR the sample rate that is defined by the user e g in the Data Aquisition dialog box in the UO Analyzer application and which is used as the basis for analysis or output e Usable I Q Analysis bandwidth the bandwidth r
134. No PPDUs of REQuired type This bit is set if an IQ measurement is performed and no PPDUs of the specified type are detected 3 GATE length too small This bit is set if gating is used in a measurement and the gate length is not set sufficiently large enough 4 PPDU count too small This bit is set if a PVT measurement is performed with gating active and there is not at least 1 PPDU within the gate lines 5 Auto level OVERIoad This bit is set if a signal overload is detected when an auto level measurement is performed 6 Auto level NoSIGnal This bit is set if no signal is detected by the auto level measurement 7 14 These bits are not used 15 This bit is always 0 9 11 2 Querying the Status Registers The following commands are required to query the status of the R amp S FSW and the WLAN application For details on the common R amp S FSW status registers refer to the description of remote control basics in the R amp S FSW User Manual General Status Register Commands eese enne denen nnt 226 Reading Out the EVENT Part cierre ereneeene rennes nnne kun nen Rn dnte 226 Reading Out the CONDIton PAM eeneg tert eorr tet cr re ee tr rte receta 226 Controlling the ENABIG Part ierat dace nene 227 Controlling the Negative Transition Pali ione rra t etna ccce uin 227 Controlling the Positive Transition Part 228 LEE User Manual 1173 9357 02 06 225 R amp SS9FSW K91 Remote Commands for WLAN Measurements m
135. Out Trigger Source Level Mode Level 0 0 dBm Drop Out Time 8 0 us Hysteresis 3 0 dB Holdoff 0 0 s External triggers from one of the TRIGGER INPUT OUTPUT connectors on the R amp S FSW are configured in a separate tab of the dialog box User Manual 1173 9357 02 06 84 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Trigger Source Trigger In Out Trigger 2 Output Type E Level Low Pulse Length Send Trigger JL Trigger 3 Input Output For more information on trigger settings and step by step instructions on configuring trig gered measurements see the R amp S FSW User Manual Tigger Source SERI echo dede euet AE bh a Turba EM uS a ea Ri 85 L Trigger oi EDD UL TM 86 L 21 5 NINE 86 L Extemal Tigger 1 2 8 e sesenta nata cria nsekndd 86 di c 86 GE Le PONET aaia Tin T T ME 87 A CNN NN 87 ul teen Bt ala ak Daca spectra ad alana 87 El Eco RENE 87 L Trigger Level Mode 88 E III MEME PCM 88 L Repetition Internal MENO EU UU TM 88 L ve TT EEN 88 EE tu o NERONE RPM PR 88 1 PPM 89 L Trigger Hedgehogs 89 R E EE 89 e MO EE 89 L Output EE 90 dto m ade 90 L Pulse ois serene Etpe etis ient op tdi 90 B 45 2 TNR TET mer tone 90 Trigger Source Settings The Trigger Source settings define when data is captured User Manual 1173 9357 02 06 85
136. R amp S FSW The R amp S FSW automatically recognizes the data it receives regardless of the format Parameters Format ASCii ASCii format separated by commas This format is almost always suitable regardless of the actual data format However the data is not as compact as other formats may be REAL 32 32 bit IEEE 754 floating point numbers in the definite length block format In the Spectrum application the format setting REAL is used for the binary transmission of trace data For I Q data 8 bytes per sample are returned for this format set ting UINT In the R amp S FSW WLAN application bitstream data can be sent as unsigned integers format to improve the data transfer speed com pared to ASCII format RST ASCII Example FORM REAL 32 Usage SCPI confirmed TRACe lt n gt DATA lt ResultType gt This command queries current trace data and measurement results from the window previously selected using DISPlay WINDow lt n gt SELect As opposed to the R amp S FSW base unit the window suffix lt n gt is not considered in the R amp S FSW WLAN application Use the DISPlay WINDow lt n gt SELect to select the window before you query trace results For details see chapter 9 9 4 Measurement Results for TRACe lt n gt DATA TRACE lt n gt on page 212 User Manual 1173 9357 02 06 210 R amp SS9FSW K91 Remote Commands for WLAN Measurements Retrieving Results Suffix n irrelevant P
137. R amp SSFSW K91 WLAN Measurements User Manual Da l hanner I aug Config Symb 1 57 Symb Symb 570 Carrier 1173 9357 02 06 ROHDE amp SCHWARZ Test amp Measurement User Manual This manual applies to the following R amp S FSW models with firmware version 1 70 and higher e R amp S FSW8 1312 8000K08 e R amp S FSW13 1312 8000K13 e R amp S FSW26 1312 8000K26 R amp S9FSWA3 1312 8000K43 e R amp S FSW50 1312 8000K50 Se Dae The following firmware options are described es R amp S FSW K91 WLAN 802 11a 1313 1500 02 e R amp S FSW K91ac WLAN 802 1 1ac 1313 4209 02 e R amp S FSW K91n WLAN 802 11n 1313 1516 02 The firmware of the instrument makes use of several valuable open source software packages For information see the Open Source Acknowledgement on the user documentation CD ROM included in delivery Rohde amp Schwarz would like to thank the open source community for their valuable contribution to embedded computing 2013 Rohde amp Schwarz GmbH amp Co KG M hldorfstr 15 81671 M nchen Germany Phone 49 89 41 29 0 Fax 49 89 41 29 12 164 E mail info rohde schwarz com Internet www rohde schwarz com Subject to change Data without tolerance limits is not binding R amp S is a registered trademark of Rohde amp Schwarz GmbH amp Co KG Trade names are trademarks of the owners The following abbreviations are used throughout this manua
138. RMat MCSindex are analyzed DEMod All PPDUs will be analyzed according to the MCS index specified by SENSe DEMod FORMat MCSindex RST FBURst Example SENS DEM FORM MCS MODE MEAS SENS DEM FORM MCS 1 Manual operation See MCS Index to use on page 98 SENSe DEMod FORMat NSTSindex Index Defines the the PPDUs taking part in the analysis depending on their Nsts This command is only available for the IEEE 802 11 ac standard This command is available for DEM FORM NSTS MODE MEAS or DEM FORM NSTS MODE DEM see SENSe DEMod FORMat NSTSindex MODE on page 171 Parameters Index Example SENS DEM FORM NSTS MODE MEAS SENS DEM FORM NSTS 1 Manual operation See Nsts on page 99 SENSe DEMod FORMat NSTSindex MODE Mode Defines the the PPDUs taking part in the analysis depending on their Nsts This command is only available for the IEEE 802 11 ac standard LEE User Manual 1173 9357 02 06 171 R amp S FSW K91 Remote Commands for WLAN Measurements 9 5 8 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters lt Mode gt FBURst ALL MEASure DEMod FBURst The Nsts of the first PPDU is detected and subsequent PPDUs are analyzed only if they have the same Nsts corresponds to Auto same type as first PPDU ALL All recognized PPDU
139. RST OFF Manual operation See Swap Q on page 83 ERREUR E N User Manual 1173 9357 02 06 151 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 5 4 2 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe SWEep TIME Time This command defines the sweep or data capture time Parameters Time refer to data sheet RST AUTO is set to ON Example SWE TIME 10s Usage SCPI confirmed Manual operation See Capture Time on page 83 TRACe IQ SRATe lt SampleRate gt This command sets the final user sample rate for the acquired UO data Thus the user sample rate can be modified without affecting the actual data capturing settings on the R amp S FSW Note The smaller the user sample rate the smaller the usable UO bandwidth see chap ter A 1 Sample Rate and Maximum Usable I Q Bandwidth for RF Input on page 230 Parameters lt SampleRate gt The valid sample rates are described in chapter A 1 Sample Rate and Maximum Usable UO Bandwidth for RF Input on page 230 Range 100 Hz to 10 GHz continuously adjustable RST 32 MHz Manual operation See Input Sample Rate on page 83 Configuring Triggered Measurements The following commands are required to configure a triggered measurement in a remote environment The tasks for manual operation are described in chapter 5 3 5 2 Trigger Settings on page 84 The oPC command should be used after
140. SS SENSe DEMod FORMat BANalyze DURation EQUal on page 175 SENSe DEMod FORMat BANalyze DBYTes EQUal on page 174 Min Max No of Data Symbols IEEE 802 11a g OFDM ac n If the Equal PPDU Length setting is enabled the number of data symbols defines the exact length a PPDU must have to be considered for analysis T User Manual 1173 9357 02 06 109 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance If the Equal PPDU Length setting is disabled you can define the minimum and maximum number of data symbols a PPDU must contain to be considered in measurement analysis Remote command SENSe DEMod FORMat BANalyze SYMBols MIN on page 177 Min Max Payload Length IEEE 802 11b g DSSS If the Equal PPDU Length setting is enabled the payload length defines the exact length a PPDU must have to be considered for analysis If the Equal PPDU Length setting is disabled you can define the minimum and maximum payload length a PPDU must contain to be considered in measurement analysis The payload length can be defined as a duration in us or a number of bytes only if specific PPDU modulation and format are defined for analysis see PPDU Format to measure PSDU Modulation to use on page 102 Remote command SENSe DEMod FORMat BANalyze DBYTes MIN on page 175 SENSe DEMod FORMat BANalyze DURation MIN on page 176 EN
141. STA Tekina eaa Erp Eee e ERE MEE aan MORE E EE FEE E ER MMEMorny EOAD SEM STATe ier techo ke randa eh cocta ene iaeia ae ved atat iana aaa e EENS Cue ene Fade n aga MMEMory STORS amp IQ STAT6 euirei rettet rentrer grs terri reta i enu re RE ak a ga sese enean OUTPut TRIGger lt port gt DIRection OUTPut TRIGgersport BT EE OUTPutTRIGger lt port O1Y Re EE OUTburTRlGoerzportz PU GelMMedate enne enne nnne nnns nnne 159 OUTbutTRlGoer zportz PULL GelENG nennen ennt ensis nnns nnns 160 STATU s OPERation eeler 226 STATus OPERation ENABle STATUs OPERation N RansSition EE 227 STATus OPERation PTRansition esiessssessssssesseseeeenenee enne nnn nate ater s s hne rines atre nr rennen enn 228 STAT s OPERationEEVENII 55 etri pes eter rne ena ET PP CEPS Eed EENS 226 STATUS PRESL EE 226 STATusOUEG onable ACL mt CONDiton tenente nennen ee enses 226 STATus QUEStionable ACPLimit ENABle 227 STATusOUEGtonable AC jmnN Tanson 227 SGTATusOUEG onable AC mt P Ransiton nennen nnne nennen nt nnnr enn nnnn en 228 STATusOUEG onable ACL Im EVEN 226 STATus QUEStIonable CONDItIOR 2 reir recu teet aere re etapa sine od eee aot A 226 STATusOUEG onable ENAble eene ennt nest ernst n nettes eere n nnns inns innen nennen 227 STATus QUEStionable LIMit lt n gt CONDition 227 STATusOUEG onable LU lMitnzENAbBle eene tne tenete nennen nennen nnns 227 SGTATusOUEGtonable lU lMitznzNiRansiton eene eene rennen nnn nnne nnn 227 STATu
142. STBC Field Auto same type as first PPDU Data Rate Mb s BOOns GI 400ns GI QPSK 58 5 65 Modulation Guard Interval Length Fig 5 2 Demodulation settings for IEEE 802 11ac standard User Manual 1173 9357 02 06 96 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance PPDU Analysis EE 97 PPDU Format to measufe x edt D pe e vea a RH E Md Eas 97 Channel Bandwidth to measure CBW etes Lett eem tue aea et en nme a PLE Lada e RR RARE 98 MCS INGSK SOCII E 98 MCI Index scs nec et de Mee NEE 99 NSIS TO EE 99 MP M Hcr 99 CS REN li CT 99 Table Ino TEE 100 Guard Interval Lengi ecca TEE ees 101 PPDU Analysis Mode Defines whether all or only specific PPDUS are to be analyzed Auto same type as first PPDU The signal symbol field i e the PLCP header field of the first recog nized PPDU is analyzed to determine the details of the PPDU All PPDUS identical to the first recognized PPDU are analyzed All subsequent settings are set to Auto mode Auto individually for each PPDU All PPDUs are analyzed User defined User defined settings define which PPDUs are analyzed This setting is automatically selected when any of the subsequent settings are changed to a value other than Auto Remote command SENSe DEMod FORMat BCONtent AUTO on page 170 PPDU Format to measure Defines which PPDU formats are to be included in the analysis De
143. Sample rate Maximum UO bandwidth 100 Hz to 35 MHz proportional up to maximum 28 MHz 35 MHz to 10 GHz 28 MHz User Manual 1173 9357 02 06 231 R amp S9FSW K91 Annex Reference Sample Rate and Maximum Usable UO Bandwidth for RF Input R amp S FSW with option B40 or U40 I Q Bandwidth Extension sample rate 100 Hz 10 GHz maximum bandwidth 40 MHz Sample rate Maximum UO bandwidth 100 Hz to 50 MHz proportional up to maximum 40 MHz 50 MHz to 10 GHz 40 MHz R amp S FSW with option B80 or U80 I Q Bandwidth Extension sample rate 100 Hz 10 GHz maximum bandwidth 80 MHz Sample rate Maximum UO bandwidth 100 Hz to 100 MHz proportional up to maximum 80 MHz 100 MHz to 10 GHz 80 MHz R amp S FSW with activated option B160 or U160 I Q Bandwidth Extension sample rate 100 Hz 10 GHz maximum bandwidth 160 MHz Sample rate Maximum UO bandwidth 100 Hz to 200 MHz proportional up to maximum 160 MHz 200 MHz to 10 GHz 160 MHz User Manual 1173 9357 02 06 232 Sample Rate and Maximum Usable UO Bandwidth for RF Input Usable UO bandwidth UO bandwidths for RF input 160 MHz Activated option L y eme 150 FIT ATT i THT SULEELEEELEE vw ATP _ TTT TTT TTI YT AT M LLLELEELELELELELTE TTL ALLL nS 80 or deactivated option B160 U160 ATT IOC CT i AA ET EE PLATT BEN 30 20 ACCEL _ Option B28 U28 Without BW 10 extension options or B8 2
144. Se DEMod FORMat BANalyze DBYTes MAX on page 175 ENSe DEMod FORMat BANalyze DURation MAX on page 176 PVT Average Length IEEE 802 11b g DSSS Defines the number of samples used to adjust the length of the smoothing filter for PVT measurement For details see PvT Full PPDU on page 31 Remote command CONFigure BURSt PVT AVERage on page 173 PVT Reference Power IEEE 802 11b g DSSS Sets the reference for the rise and fall time in PVT calculation to the maximum or mean PPDU power For details see PvT Full PPDU on page 31 Remote command CONFigure BURSt PVT RPOWer on page 173 Peak Vector Error Meas Range IEEE 802 11 B G DSSS Displays the used measurement range for peak vector error measurement for reference only All Symbols Peak Vector Error results are calculated over the complete PPDU PSDU only Peak Vector Error results are calculated over the PSDU only Remote command CONFigure WLAN PVERror MRANge on page 173 __L_L_L_L_LL T T e 1 L 1 LeLAALLLLLLLLLL L LALLLULI J User Manual 1173 9357 02 06 110 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance 5 3 10 Result Configuration You can configure which results are displayed in Result Summary displays see Result Summary Detailed on page 32 and Result Summary Global on page 33 However the results are always calculated r
145. T Q 112 uc 152 Messages Signal Field cnr tren eere nnde 124 Modulation erue m Inverted UO remote m On CR e EE EE PPDU remote 229 PS ee e Pet 98 105 Modulation Accuracy aulici 13 Modulation and Coding Scheme SCS MCS S 98 105 MSR ACLR RRESUILS remote cerent teretes 207 Multiple Measurement channels esses 66 N Ness PPDUS certi rete Ctt 107 163 Net Stfg 4 nue inte arent eere eite seit prts 47 Noise Additive white Gaussian AWG eseese 47 SOUCO PERPE 61 75 Nsts KEE 99 171 Number of samples Displayed iir eie e tete tet 10 O OBW Configuring cdma2000 sss 117 Dini c 41 Occupied bandwidth e 41 Offset Amplification Oe 17 CAME T 17 t le EE 78 Phase angle I Q we 18 Quadrature EE 18 Reference level A 80 Options Bandwidth extension eessesssssse 230 231 Electronic attenuation B25 oo eee eee 81 High pass filter B13 T Preamplifier B24 sess Output Configuration remote sss 144 Configuration softkey sss 75 INOISE SOUFCG csi ccr ar rar rd 61 75 Parameters Sample rate definition sssesssssss 230 SGUINGS a reine ort E etie eh eere 75 ul EE 76 89 Overload Elei iiri acr erento ei nre 61 RF input remote
146. TA MINimum FETOCHBURGSCEVM PILO AVtChage aiara esaera aaa araa ar iaaa EAA E APEE E REKE E EAN ERAEN 201 FETCRh BURSEEVM PILOEMANIImUEY cuta acetone tre ananda aeaaaee Eee pa Coe M rerba Reda Edd 201 FETCh BURSEEVMEPILot MINIEUETI dcr rr eere t rh tr e e ee tree ee EE Ee 201 FETOChBURGCEERRor AVERage EAEE AA EAEE AEAE EESHA EEEren EEEa E nennen 201 SSS N User Manual 1173 9357 02 06 242 R amp S FSW K91 List of Remote Commands WLAN FETOChBURGSCEERRorMANImum EnEn nE EAEE AS EAEE AS EAEE AA EAE En EEEren ennnen 201 FETCh BURStFERROF MINIMUMI iria eee Ee eene e ric aere EAEE E NEA 201 FETCh BURG GlM alance AVEhRage 201 FETCh BURSt GIMBalance MAXIMUM cccsesccsssccscccsscccessesensccsscceesaecsecaecaeceesaessaceesaucnetessaacesaeessanaenasense 201 FETCh BURG GlM alance MiNimum ratane rnent nnee eneee 201 FETCIEIBURSEIQOFISeEAVERAgS EE 202 FETCh BURSEIQOFfset MAXImUtT cuocere teer t ee tn eno Pe AR Reed reus danda e Re 202 FETGCh BURSEIOOFfSeEMINIEYT sitae chere nort err re ee eere rper aper eve ee Ve ee ved les 202 FETChBURGSCLENGibe raioni enairada erain a ankariin aiaiai aian aeni 199 FETCH BURSUPAY d KE 202 e Cat eu N EE E 202 FETCh BURSEPREamble 5 rre nie a rite E ERR ra ca YER XXE ER REX RR NT ala Fe c Pe dE YR RE eR 202 FETCh BURSEQUADOIfSet AVERAge3 tret prre rir re AY D E e e EROR E eee EE Rd eg 202 FETCh BURSt QUADoffset MAXimum FETCh BURSEQUADOTfset
147. The index of a window on the other side of the splitter Position New vertical or horizontal position of the splitter as a fraction of the screen area without channel and status bar and softkey menu The point of origin x 0 y 0 is in the lower left corner of the screen The end point x 100 y 100 is in the upper right corner of the screen See figure 9 1 The direction in which the splitter is moved depends on the screen layout If the windows are positioned horizontally the splitter also moves horizontally If the windows are positioned vertically the splitter also moves vertically Range 0 to 100 Example LAY SPL 1 3 50 Moves the splitter between window 1 Frequency Sweep and 3 Marker Table to the center 50 of the screen i e in the figure above to the left Example LAY SPL 1 4 70 Moves the splitter between window 1 Frequency Sweep and 3 Marker Peak List towards the top 70 of the screen The following commands have the exact same effect as any com bination of windows above and below the splitter moves the splitter vertically AY SPL 3 2 70 AY SPL 4 1 70 AY SPL 2 1 70 LAYout WINDow n ADD lt Direction gt lt WindowType gt This command adds a measurement window to the display Note that with this command the suffix n determines the existing window next to which the new window is added as opposed to LAYout ADD WINDow for which the existing window
148. Time Spectrum RTIM Real Time Spectrum R amp S FSW K160R Note the default channel name is also listed in the table If the specified name for a new channel already exists the default name extended by a sequential number is used for the new channel User Manual 1173 9357 02 06 134 R amp S9FSW K91 Remote Commands for WLAN Measurements Activating WLAN Measurements INSTrument REName ChannelName1 lt ChannelName2 gt This command renames a measurement channel Parameters lt ChannelName1 gt lt ChannelName2 gt Example String containing the name of the channel you want to rename String containing the new channel name Note that you can not assign an existing channel name to a new channel this will cause an error INST REN Spectrum2 Spectrum3 Renames the channel with the name Spectrum2 to Spectrum3 INSTrument SELect lt ChannelType gt lt ChannelName gt This command activates a new measurement channel with the defined channel type or selects an existing measurement channel with the specified name See also INSTrument CREate NEW on page 132 For a list of available channel types see INSTrument LIST on page 133 Parameters lt ChannelType gt lt ChannelName gt Example Channel type of the new channel For a list of available channel types see table 9 3 WLAN WLAN option R amp S FSW K91 String containing the name of the channel INST WLAN
149. according to the first measured PPDU Which of the WLAN demodulation parameter values are supported depends on the selected digital standard some are also interdependant Table 4 1 Supported modulation formats PPDU formats and channel bandwidths depending on stand ard Standard Modulation formats PPDU formats Channel bandwidths IEEE 802 11a g BPSK 6 Mbps amp 9 Mbps HT 5 MHz 10 MHz 20 MHz OFDM QPSK 12 Mbps amp 18 Mbps 16QAM 24 Mbps amp 36 Mbps 64QAM 48 Mbps amp 54 Mbps IEEE 802 11ac 16QAM VHT 20 MHz 40 MHZ 80 MHZ 64QAM 160 MHz 256QAM IEEE 802 11 g DBPSK 1 Mbps Short PPDU 22 MHz DSSS DQPSK 2 Mbps Long PPDU CCK 5 5 Mbps amp 11 Mbps PBCC 5 5 Mbps amp 11 Mbps IEEE 802 11n SISO HT MF Mixed format 20 MHz 40 MHz BPSK 6 5 7 2 13 5 amp HT GF Greenfield format 15 Mbps QPSK 13 14 4 19 5 21 7 27 30 40 5 amp 45 Mbps 16QAM 26 28 9 39 43 3 54 60 81 amp 90 Mbps 64QAM 52 57 8 58 5 65 72 2 108 121 5 135 120 135 amp 150 Mbps MIMO depends on the MCS index requires R amp S FSW bandwidth extension option see chapter A 1 Sample Rate and Maximum Usable 1 Q Bandwidth for RF Input on page 230 User Manual 1173 9357 02 06 60 R amp SS9FSW K91 Measurement Basics Receiving Data Input and Providing Data Output 4 6 Receiving Data Input and Providing Data Output The R amp S FSW
150. acy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt PAYLoad This command returns the average power measured in the payload of all analyzed PPDUs Usage Query only FETCh BURSt PEAK This command returns the Peak power in dBm measured during the measurement time Usage Query only FETCh BURSt PREamble This command returns the average power measured in all analyzed PPDU preambles Usage Query only FETCh BURSt QUADoffset AVERage FETCh BURSt QUADoffset MAXimum FETCh BURSt QUADoffset MINimum This command returns the average maximum or minimum quadrature offset of symbols within a PPDU This value indicates the phase accuracy For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt RMS AVERage FETCh BURSt RMS MAXimum FETCh BURSt RMS MINimum This command returns the average maximum or minimum RMS power in dBm for all analyzed PPDUs For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 ERREUR EA N User Manual 1173 9357 02 06 202 R amp S FSW K91 Remote Commands for WLAN Measurements 9 9 1 3 Retrieving Results Usage Query only FETCh BURSt SYMBolerror AVERage FETCh BURSt SYMBolerror MAXimum FETCh BURSt SYMBolerror MINimum This command returns the average maximum or minimum percentage of symbols that were outside the allowed
151. ailable for most operating systems The advantage of tar files is that the archived files inside the car file are not changed not compressed and thus itis possible to read the I Q data directly within the archive without the need to unpack untar the tar file first User Manual 1173 9357 02 06 234 R amp SS9FSW K91 Annex Reference UO Data File Format iq tar Sample iq tar files If you have the optional R amp S FSW VSA application R amp S FSW K70 some sample iq tar files are provided in the C R S Instr user vsa DemoSignals directory on the R amp S FSW Contained files An iq tar file must contain the following files e Q parameter XML file e g xyz xml Contains meta information about the UO data e g sample rate The filename can be defined freely but there must be only one single UO parameter XML file inside an iq tar file e Q data binary file e g xyz complex fl0oat32 Contains the binary UO data of all channels There must be only one single UO data binary file inside an iq tar file Optionally an iq tar file can contain the following file e Q preview XSLT file e g open IgTar xml file in web browser xslt Contains a stylesheet to display the UO parameter XML file and a preview of the UO data in a web browser A sample stylesheet is available at http www rohde schwarz com file open IqTar xml file in web browser xslt A 2 14 I Q Parameter XML File Specification The content o
152. al measurement settings The name of the new channel is the same as the copied channel extended by a con secutive number e g Spectrum Spectrum 2 The channel to be duplicated must be selected first using the INST SEL command This command is not available if the MSRA Master channel is selected Example INST SEL Spectrum INST CRE DUPL Duplicates the channel named Spectrum and creates a new mea surement channel named Spectrum 2 Usage Event INSTrument CREate NEW lt ChannelType gt lt ChannelName gt This command adds an additional measurement channel The number of measurement channels you can configure at the same time depends on available memory Parameters lt ChannelType gt Channel type of the new channel For a list of available channel types see table 9 3 SSS SS SSS User Manual 1173 9357 02 06 132 R amp SS9FSW K91 Remote Commands for WLAN Measurements aS H Activating WLAN Measurements lt ChannelName gt String containing the name of the channel The channel name is displayed as the tab label for the measurement channel Note If the specified name for a new channel already exists the default name extended by a sequential number is used for the new channel see table 9 3 Example INST CRE SAN Spectrum 2 Adds an additional spectrum display named Spectrum 2 INSTrument CREate REPLace lt Cha
153. al of 2 symbols for the estimation of H S leads to a nearly error free channel estimate In the following equalizer block HI is compensated by the channel estimate The resulting channel compensated sequence is described by ys The user may either choose the coarse channel estimate HS from the long symbol or the nearly error free channel estimate HL from the payload for equalization If the improved estimate AtS is used a 2 dB reduction of the subsequent EVM measurement can be expected According to the IEEE 802 11a measurement standard 6 the coarse channel estimation ALS from the long symbol has to be used for equalization Therefore the default setting of the R amp S FSW WLAN application is equalization from the coarse channel estimate derived from the long symbol Calculating error parameters In the last block the parameters of the demodulated signal are calculated The most important parameter is the error vector magnitude of the sub carrier k of the current packet 1 nof _ packets EVM In 3 EVM counter nof packets counter 1 Error vector magnitude of the subcarrier k in current packet 4 6 Furthermore the packet error vector magnitude is derived by averaging the squared EVM versus k 1 26 EVM EVM k 26 k 0 Error vector magnitude of the entire packet 4 7 Finally the average error vector magnitude is calculated by averaging the packet EVM of all nof_symbols detected pac
154. allas All PPDUSs are analyzed assuming the specified STBC field content STBC 1 Nsts 2Nss D1 I EEE 802 11AC Remote command CONFigure WLAN STBC AUTO TYPE on page 166 Table info overview Depending on the selected channel bandwidth MCS index or NSS STBC the relevant information from the modulation and coding scheme MCS as defined in the WLAN 802 11 standard is displayed here This information is for reference only for example so you can determine the required data rate T User Manual 1173 9357 02 06 100 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Guard Interval Length Defines the PPDUs taking part in the analysis depending on the guard interval length Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display GI column see Signal Field on page 35 Auto same All PPDUs using the guard interval length identical to the first recog type as first nized PPDU are analyzed PPDU A1st Auto individu All PPDUs are analyzed ally for each PPDU AI Meas only Only PPDUs with short guard interval length are analyzed Short MS Meas only Only PPDUs with long guard interval length are analyzed Long ML Demod allas All PPDUs are demodulated assuming short guard interval length short DS Demod allas All PPDUs are demodulated assuming long guard int
155. alyzed Number of PPDUs analyzed in entire signal if available PPDUs in physical channel ERREUR EA R User Manual 1173 9357 02 06 15 R amp S9FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Parameter Peak vector error Description Peak vector error EVM over the complete PPDU including the preamble in 96 and in dB calculated according to the IEEE 802 11b or g DSSS definition of the normalized error vector magnitude see Peak Vector Error IEEE method on page 21 The corresponding limits specified in the standard are also indicated PPDU EVM EVM Error Vector Magnitude over the complete PPDU including the preamble in and dB UO offset dB Transmitter center frequency leakage relative to the total Tx channel power see chapter 3 1 1 1 I Q Offset on page 17 Gain imbalance dB Amplification of the quadrature phase component of the signal relative to the amplification of the in phase component see chapter 3 1 1 2 Gain Imbal ance on page 17 Quadrature error Center frequency error Hz Measure for the crosstalk of the Q branch into the I branch see Gain imbal ance UO offset quadrature error on page 56 Frequency error between the signal and the current center frequency of the R amp S FSW the corresponding limits specified in the standard are also indica ted The absolute frequenc
156. ames commands coding samples and screen output are distin program code guished by their font Input Input to be entered by the user is displayed in italics Links Links that you can click are displayed in blue font References References to other parts of the documentation are enclosed by quotation marks 1 3 2 Conventions for Procedure Descriptions When describing how to operate the instrument several alternative methods may be available to perform the same task In this case the procedure using the touchscreen is described Any elements that can be activated by touching can also be clicked using an additionally connected mouse The alternative procedure using the keys on the instru ment or the on screen keyboard is only described if it deviates from the standard oper ating procedures User Manual 1173 9357 02 06 7 Conventions Used in the Documentation The term select may refer to any of the described methods i e using a finger on the touchscreen a mouse pointer in the display or a key on the instrument or on a keyboard R amp S FSW K91 Welcome to the WLAN Application Starting the WLAN Application 2 Welcome to the WLAN Application The R amp S FSW WLAN application extends the functionality of the R amp S FSW to enable accurate and reproducible Tx measurements of a WLAN device under test DUT in accordance with the standards specified for the device the following standards are cur rently supported
157. amp S FSW which you activate using the MODE key on the front panel gt To select a frequency sweep measurement type do one of the following e Tap the Overview softkey In the Overview tap the Select Measurement button Select the required measurement e Press the MEAS key on the front panel In the Select Measurement dialog box select the required measurement The R amp S FSW WLAN application uses the functionality of the R amp S FSW base system Spectrum application to perform the WLAN frequency sweep measurements Some parameters are set automatically according to the WLAN 802 11 standard the first time a measurement is selected since the last PRESET operation These parameters can be changed but are not reset automatically the next time you re enter the measurement Refer to the description of each measurement type for details The main measurement configuration menus for the WLAN frequency sweep measure ments are identical to the Spectrum application For details refer to Measurements in the R amp S FSW User Manual The measurement specific settings for the following measurements are available via the Overview e Channel Power ACLR Measurements eeeeeeeeseeeeee eene 115 e Spectrum Emission MASK c eed ee cete ta kraft pdn ada rte hn enu Ra a iadaan 116 e Occupied Bandwidth ccce tete e E inte dee 117 oco e 118 5 4 1 Channel Power ACLR Measurements The Adjace
158. ange in which the signal remains undistorted in regard to amplitude characteristic and group delay this range can be used for accurate analysis by the R amp S FSW For the UO data acquisition digital decimation filters are used internally The passband of these digital filters determines the maximum usable VO bandwidth In consequence signals within the usable UO bandwidth passband remain unchanged while signals outside the usable UO bandwidth passband are suppressed Usually the suppressed signals are noise artifacts and the second IF side band If frequencies of interest to you are also suppressed you should try to increase the output sample rate since this increa ses the maximum usable UO bandwidth o Bandwidth extension options The maximum usable UO bandwidth provided by the R amp S FSW in the basic installation can be extended by additional options These options can either be included in the initial installation B options or updated later U options The maximum bandwidth provided by the individual option is indicated by its number for example B80 extends the band width to 80 MHz Note that the U options as of U40 always require all lower bandwidth options as a pre requisite while the B options already include them Max usable Required B option Required U option s Q BW 10 MHz 28 MHz B28 U28 40 MHz B40 U28 U40 or B28 U40 The bandwidth extension option R amp S FSW B320 U320 requires
159. arameters lt ResultType gt Selects the type of result to be returned TRACE TRACE6 Returns the trace data for the corresponding trace Note that for the default WLAN I Q measurement Modulation Accuracy Flatness and Tolerance only 1 trace per window TRACE is available LIST Returns the results of the peak list evaluation for Spectrum Emis sion Mask measurements Return values lt TraceData gt For more information see tables below Example DISP WIND2 SEL TRAC TRACE3 Queries the data of trace 3 in window 2 Manual operation See Spectrum Emission Mask on page 40 Table 9 10 Return values for TRACE1 to TRACE6 parameter For UO data traces the results depend on the evaluation method window type selected for the current window see LAYout ADD WINDow on page 186 The results for the various window types are described in chapter 9 9 4 Measurement Results for TRACe lt n gt DATA TRACE lt n gt on page 212 For RF data traces the trace data consists of a list of 1001 power levels that have been measured The unit depends on the measurement and on the unit you have currently set For SEM measurements the x values should be queried as well as they are not equi distant see TRACe lt n gt DATA X on page 212 Table 9 11 Return values for LIST parameter This parameter is only available for SEM measurements For each sweep list range you have defined range 1 n the co
160. as only if Only PPDUs with the specified Ness value are analyzed Ness lt x gt M esa Demod allas All PPDUs are analyzed assuming the specified Ness value Ness lt x gt Remote command CONFigure WLAN EXTension AUTO TYPE on page 163 Table info overview Depending on the selected channel bandwidth MCS index or NSS STBC the relevant information from the modulation and coding scheme MCS as defined in the WLAN 802 11 standard is displayed here This information is for reference only for example so you can determine the required data rate Guard Interval Length Defines the PPDUs taking part in the analysis depending on the guard interval length Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display GI column see Signal Field on page 35 Auto same All PPDUs using the guard interval length identical to the first recog type as first nized PPDU are analyzed PPDU A1st ERREUR EA a User Manual 1173 9357 02 06 107 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Auto individu All PPDUs are analyzed ally for each PPDU Al Meas only Only PPDUs with short guard interval length are analyzed Short MS Meas only Only PPDUs with long guard interval length are analyzed Long ML Demod allas All PPDUs are demodulated assuming short guard interval length
161. asurement can be performed on the R amp S FSW at any time If one mea surement is running and you start another or switch to another channel the first mea surement is stopped In order to perform the different measurements you configured in multiple channels you must switch from one tab to another However you can enable a Sequencer function that automatically calls up each activated measurement channel in turn This means the measurements configured in the channels are performed one after the other in the order of the tabs The currently active measure ment is indicated by a 8 symbol in the tab label The result displays of the individual channels are updated in the corresponding tab as well as the MultiView as the meas urements are performed Sequencer operation is independant of the currently dis played tab for example you can analyze the SEM measurement while the modulation accuracy measurement is being performed by the Sequencer For details on the Sequencer function see the R amp S FSW User Manual The Sequencer functions are only available in the MultiView tab SUM rcli E 67 Sequencer le TEE 67 Sequencer State Activates or deactivates the Sequencer If activated sequential operation according to the selected Sequencer mode is started immediately Remote command SYSTem SEQuencer on page 196 INITiate SEQuencer IMMediate on page 195 INITiate SEQuencer ABORt on page 195 Sequencer Mode Defines how often wh
162. asurements SYST SEQ OFF Manual operation See Sequencer State on page 67 9 9 Retrieving Results The following commands are required to retrieve the results from a WLAN measurement in a remote environment Before retrieving measurement results check if PPDU synchronization was successful or not by checking the status register see chapter 9 11 1 The STATus QUEStiona ble SYNC Register on page 224 If no PPDUs were found STAT QUES SYNC COND returns 0 see STATus QUEStionable SYNC CONDition on page 227 The OPC command should be used after commands that retrieve data so that subse quent commands to change the trigger or data capturing settings are held off until after the data capture is completed and the data has been returned Numeric Modulation Accuracy Flatness and Tolerance Results 198 Numeric Results for Frequency Sweep Measurements AAA 206 Retrieving Trace RESUS e reae tnt e t eura iene 210 Measurement Results for TRACe lt n gt DATA TRACEens 212 Importing and Exporting UO Data and Results 220 ERREUR M User Manual 1173 9357 02 06 197 R amp SS9FSW K91 Remote Commands for WLAN Measurements Retrieving Results 9 9 1 Numeric Modulation Accuracy Flatness and Tolerance Results The following commands describe how to retrieve the numeric results from the standard WLAN measurements nals are described in chapter 9 9 2 Numeric Results for Fre
163. ated egen of their visibility User Manual 1173 9357 02 06 32 R amp S FSW K91 Measurements and Result Displays uu M eae WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Tx channel Tx All Quadrature offset dB Gain imbalance dB Quadrature offset PPDU power dBm Crest factor dB Receive channel Rx All e PPDU power dBm e Crest factor dB Bitstream Stream All e Pilot bit error rate e EVM all carriers dB e EVM data carriers dB e EVM pilot carriers dB For details on the individual parameters and the summarized values see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Remote command LAY ADD 1 RIGH RSD see LAYout ADD WINDow on page 186 Result Summary Global The global result summary provides measurement results based on the complete signal consisting of all channels and streams The observation length is the number of PPDUs to be analyzed as defined by the Evaluation Range gt Statistics settings In contrast the detailed result summary provides results for each individual channel and stream al Channel 1 Limit Limit Fig 3 12 Global result summary for IEEE 802 11a g OFDM standards T User Manual 1173 9357 02 06 33 R amp S FSW K91 Measurements and Result Displays 1 Result Summary Global No of PPDUs Recognized 3 Analyzed 3 Analyzed Physi
164. ation is performed the entire signal is processed RST 1 Manual operation See Power Interval Search on page 91 9 5 6 Tracking and Channel Estimation SENSe DEMad GES lIallGR 2 peor de Ehe a done REEL Ded SES 161 SENSe TRACking LEVel ccce teet tette tt tette te teens test enes 162 E EN e e ME 162 EE e ee RTE 162 SENSe TRACking TIME ccce ttt tette ett te tests sod 163 SENSe DEMod CESTimation State This command defines whether channel estimation will be done in preamble and payload or only in preamble The effect of this is most noticeable for the EVM measurement results where the results will be improved when this feature is enabled However this functionality is not supported by the IEEE 802 11 standard and must be disabled if the results are to be measured strictly according to the standard Parameters State ON OFF ON The channel estimation is performed in the preamble and the pay load The EVM results can be calculated more accurately OFF The channel estimation is performed in the preamble as required in the standard RST OFF Manual operation See Channel Estimation Range on page 92 User Manual 1173 9357 02 06 161 R amp SS9FSW K91 Remote Commands for WLAN Measurements PEHEMGNSGENE EM CDI d e Configuring the W
165. ations only the query command is available Parameters Offset Range 100 GHz to 100 GHz RST 0 Hz Example FREQ OFFS 1GHZ Usage SCPI confirmed Manual operation See Frequency Offset on page 78 Amplitude Settings The following commands are required to configure the amplitude settings in a remote environment Useful commands for amplitude settings described elsewhere e INPut COUPling on page 142 e INPut IMPedance on page 143 SENSe ADJust LEVel on page 183 Remote commands exclusive to amplitude settings CAL Culatesi UNIT POW GF m 147 es Le Ee d E no 147 EE Lee e e ER 147 DiSblavlfWiNDow nzTRACevtSCALelbRLEVel nennen 147 DISPlay WINDow n TRACe Y SCALe RLEVel OFFSet sees 148 INPutA T enualiQfi uoiceeedcteeutaa Gaara redux a Reve a ra dcr ota su de ves n E x ba Mx OE REe EO Mae EH 148 INPut ATTenuati n AD TO i riae t ineo EES 148 tel rue GN WI ee IE 149 INPUCEATT AUTO CES 149 E N User Manual 1173 9357 02 06 146 R amp SS9FSW K91 Remote Commands for WLAN Measurements c am m Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Dee P PI DC 149 NPEGAN WAL DE 150 INPUTGAIN S TAT rccsiesossc C n 150
166. atness on page 219 Remote command LAY ADD 1 RIGH SFL see LAYout ADD WINDow on page 186 or CONF BURS SPEC FLAT SEL FLAT see CONFigure BURSt SPECtrum FLATness SELect on page 138 and CONFigure BURSt SPECtrum FLATness IMMediate on page 138 T User Manual 1173 9357 02 06 38 R amp S FSW K91 Measurements and Result Displays Frequency Sweep Measurements 3 2 Frequency Sweep Measurements As described above the WLAN IQ measurement captures the UO data from the WLAN signal using a nearly rectangular filter with a relatively large bandwidth However some parameters specified in the WLAN 802 11 standard require a better signal to noise level or a smaller bandwidth filter than the UO measurement provides and must be determined in separate measurements Parameters that are common to several digital standards and are often required in signal and spectrum test scenarios can be determined by the standard measurements provided in the R amp S FSW base unit Spectrum application These measurements are performed using a much narrower bandwidth filter and they capture only the power level magni tude which we refer to as RF data of the signal as opposed to the two components provided by UO data Frequency sweep measurements can tune on a constant frequency Zero span mea surement or sweep a frequency range Frequency sweep measurement The signal cannot be demodulated based on the captur
167. ay The bitstream is derived from the constellation diagram points using the constellation bit encoding from the corresponding WLAN standard See for example EEE Std 802 11 2012 Fig 18 10 BPSK QPSK 16 QAM and 64 QAM constellation bit enco ding Thus the bitstream is NOT channel decoded For multicarrier measurements IEEE 802 11a g OFDM ac n the results are grouped by symbol and carrier ERREUR A a User Manual 1173 9357 02 06 22 R amp S FSW K91 Measurements and Result Displays b aM a WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 1 Bitstream Carrier Symbol 1 26 000010 110111 111110 23 000001 010100 0 20 011001 101010 010101 17 001010 011100 101010 14 111100 001010 001101 011011 111110 010010 111100 0 001100 001101 111100 101100 101010 100011 NULL 101010 101101 101010 011010 000101 010001 0 101101 001011 10 000110 100100 100101 13 101001 111101 101011 16 011100 111001 010010 19 110100 111001 0 22 000011 101111 101111 25 001111 111100 Carrier Symbol 2 Fig 3 7 Bitstream result display for IEEE 802 11a g OFDM ac n standards For single carrier measurements IEEE 802 11b g DSSS the results are grouped by PPDU LEE User Manual 1173 9357 02 06 23 R amp S9FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 4 Bitstream PPDU 1 PLCP Preamble 0 24 48 72 96 120 PLCP Header 0 24
168. ayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See EVM vs Carrier on page 26 CONFigure BURSt EVM ESYMbol IMMediate IEEE 802 11b and g DSSS CONFigure BURSt EVM ECHip IMMediate Both of these commands configure the measurement type to be EVM vs Chip for IEEE 802 11b and g DSSS standards For compatibility reasons the CONFigure BURSt EVM ESYMbol IMMediate command is also supported for the IEEE 802 11b and g DSSS standards However for new remote control programs use the LAYout commands see chapter 9 7 2 Working with Windows in the Display on page 185 Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Manual operation See EVM vs Chip on page 27 CONFigure BURSt EVM ESYMbol IMMediate This remote control command configures the measurement type to be EVM vs Symbol For IEEE 802 11b and g DSSS standards this command selects the EVM vs Chip result display User Manual 1173 9357 02 06 137 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG M T A wd a umm t Selecting a Measurement Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See EVM vs Chip on page 27 S
169. be determined the R amp S FSW WLAN application can provide spectral results channel flatness group delay channel phase channel impulse response and channel singular values for the physical Tx and Receiver channels and the effective channel stream Channels and carriers In an OFDM system such as WLAN the channel is divided into carriers using FFT IFFT Depending on the channel bandwidth the FFT window varies between 64 and 512 see also chapter 4 5 Demodulation Parameters Logical Filters on page 60 Some of these carriers can be used active carriers others are inactive e g guard carriers at the edges The channel can then be determined using the active carriers as known points inactive carriers are interpolated Channel Display in the Spectrum Analyzer In the R amp S FSW WLAN application channels are represented by their transmission spectrum i e the gains of the active carriers In effect a physical channel represents the transmission spectrum sent by a particular sender and received by a particular receiver antenna An effective channel on the other hand represents the transmission spectrum of a specific space time stream received by a particular receiver antenna Recognized vs Analyzed PPDUs A PPDU in a WLAN signal consists of the following parts e Preamble Information required to recognize the PPDU within the signal e Signal Field Information on the modulation used for transmission of the useful data
170. c scaling returns the power in the current unit linear scaling returns the power in W For SEM measurements the return value is the channel power of the reference range PPOWer Peak power measurements Returns the peak power The unit of the return values depends on the scaling of the y axis logarithmic scaling returns the power in the current unit linear scaling returns the power in W For SEM measurements the return value is the peak power of the reference range OBANdwidth OBWidth Occupied bandwidth Returns the occupied bandwidth in Hz Usage Query only User Manual 1173 9357 02 06 208 R amp SS9FSW K91 Remote Commands for WLAN Measurements mA X s EUE ne M Retrieving Results Manual operation See Channel Power ACLR on page 39 See Occupied Bandwidth on page 41 CALCulate lt n gt MARKer lt m gt X Position This command moves a marker to a particular coordinate on the x axis If necessary the command activates the marker If the marker has been used as a delta marker the command turns it into a normal marker Parameters Position Numeric value that defines the marker position on the x axis Range The range depends on the current x axis range Example CALC MARK2 X 1 7MHz Positions marker 2 to frequency 1 7 MHz Manual operation See Marker Table on page 43 See Marker Peak List on page 44 CALCulate STAT
171. cal Channel 0 PPDUs Min Limit Unit 1 18 IQ Offset Gain Imbalance Quadrature Error enter Freq Error Chip Clock Error Rise Time Fall Time Fig 3 13 Global result summary for IEEE 802 11b g DSSS standards The Result Summary Global contains the following information Note You can configure which results are displayed see on page 111 However the results are always calculated regardless of their visibility e Number of recognized PPDUs e Number of analyzed PPDUs e Number of analyzed PPDUs in entire physical channel if available IEEE 802 11a g OFDM ac n standards Pilot bit error rate 96 EVM all carriers dB EVM data carriers dB EVM pilot carriers dB Center frequency error Hz Symbol clock error ppm IEEE 802 11b g DSSS standards e Peak vector error e PPDU EVM e Quadrature offset e Gain imbalance User Manual 1173 9357 02 06 34 R amp S FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Quadrature error Center frequency error Chip cock error Rise time Fall time Mean power Peak power Crest power For details on the individual results and the summarized values see chapter 3 1 1 Mod ulation Accuracy Flatness and Tolerance Parameters on page 13 Remote command LAY ADD 1 RIGH RSG see LAYout ADD WINDow on page 186 Signal Field This result display shows the decoded data fro
172. can analyze signals from different input sources and provide various types of output such as noise or trigger signals 4 6 1 RF Input Protection The RF input connector of the R amp S FSW must be protected against signal levels that exceed the ranges specified in the data sheet Therefore the R amp S FSW is equipped with an overload protection mechanism This mechanism becomes active as soon as the power at the input mixer exceeds the specified limit It ensures that the connection between RF input and input mixer is cut off When the overload protection is activated an error message is displayed in the status bar INPUT OVLD and a message box informs you that the RF Input was disconnec ted Furthermore a status bit bit 3 in the STAT QUES POW status register is set In this case you must decrease the level at the RF input connector and then close the message box Then measurement is possible again Reactivating the RF input is also possible via the remote command INPut ATTenuation PROTection RESet 4 6 2 Input from Noise Sources The R amp S FSW provides a connector NOISE SOURCE CONTROL with a voltage supply for an external noise source By switching the supply voltage for an external noise source on or off in the firmware you can activate or deactive the device as required External noise sources are useful when you are measuring power levels that fall below the noise floor of the R amp S FSW itself for example when measu
173. cation is considered when the trigger level is analyzed If defined a reference level offset is also considered The input signal must be between 500 MHz and 8 GHz For details on the trigger source see Trigger Source Settings on page 85 Parameters lt TriggerLevel gt For details on available trigger levels and trigger bandwidths see the data sheet RST 20 dBm Example TRIG LEV RFP 30dBm Manual operation See Trigger Source Settings on page 85 See Trigger Level on page 88 TRIGger SEQuence SLOPe lt Type gt For all trigger sources except time you can define whether triggering occurs when the signal rises to the trigger level or falls down to it Parameters lt Type gt POSitive NEGative POSitive Triggers when the signal rises to the trigger level rising edge NEGative Triggers when the signal drops to the trigger level falling edge RST POSitive Example TRIG SLOP NEG Manual operation See Trigger Source Settings on page 85 See Slope on page 89 TRIGger SEQuence SOURce lt Source gt This command selects the trigger source T User Manual 1173 9357 02 06 156 R amp S9FSW K91 Remote Commands for WLAN Measurements EET I M X r Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance For details on the available trigger sources see Trigger Source Settings o
174. cified number of PPDUs is taken into consideration for the statistical evaluation Sweeps are performed continuously until the required num ber of PPDUs are available The number of captured and required PPDUS as well as the number of PPDUs detected in the current sweep are indicated as Analyzed PPDUs in the channel bar see Channel bar information on page 10 If disabled all valid PPDUs in the current capture buffer are considered Note that in this case the number of PPDUs contributing to the current results may vary extremely Remote command SENSe BURSt COUNt STATe on page 174 SENSe BURSt COUNt on page 174 Source of Payload Length IEEE 802 11 AC N Defines which signal source is used to determine the payload length of a PPDU L Signal IEEE 802 11 AC Determines the length of the L signal HT Signal IEEE 802 11 N Determines the length of the HT signal Estimate from signal Uses an estimated length Remote command CONFigure WLAN PAYLoad LENGth SRC on page 173 Equal PPDU Length If enabled only PPDUs with the specified Min Max Payload Length IEEE 802 11b g DSSS are considered for measurement analysis If disabled a maximum and minimum Min Max Payload Length IEEE 802 11b g DSSS can be defined and all PPDUs whose length is within this range are considered Remote command IEEE 802 11a g OFDM SENSe DEMod FORMat BANalyze SYMBols EQUal on page 177 IEEE 802 11 b g DS
175. command TRIG SOUR RFP see TRIGger SEQuence SOURce on page 156 Time Trigger Source Trigger Source Settings Triggers in a specified repetition interval Remote command TRIG SOUR TIME see TRIGger SEQuence SOURce on page 156 Power Sensor Trigger Source Trigger Source Settings Uses an external power sensor as a trigger source This option is only available if a power sensor is connected and configured Note For R amp S power sensors the Gate Mode Lvl is not supported The signal sent by these sensors merely reflects the instant the level is first exceeded rather than a time period However only time periods can be used for gating in level mode Thus the trigger LEE User Manual 1173 9357 02 06 87 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance impulse from the sensors is not long enough for a fully gated measurement the mea surement cannot be completed Remote command TRIG SOUR PSE see TRIGger SEQuence SOURce on page 156 Trigger Level Mode Trigger Source Settings By default the optimum trigger level for power triggers is automatically measured and determined at the start of each sweep for Modulation Accuracy Flatness Tolerance measurements In order to define the trigger level manually switch to Manual mode Remote command TRIG SEQ LEV POW AUTO ON see TRIGger SEQuence LEVel POWer AUTO on page 15
176. commands that retrieve data so that subse quent commands to change the selected trigger source are held off until after the sweep is completed and the data has been returned e Configuring the Triggering Condttons 152 e QContgulng the Trigger OUI ss cii ener ddr neret h deedteaaaed Aasaaadauceansaateateats 158 Configuring the Triggering Conditions TRIGO e ENT 153 TRiGger SEQuence HOLDO TIME E 153 TRIGger SEQuence IFPowerHOLDEDAOft 1 cecee retra cuoc ste ca core eR c Hone deo eoe core ena 153 TRlGoert GtOuencelltbower HvGTeresls eene enne nnns 154 TRlGoert GtOuencell EVel D bower serene enne ener enses 154 E N User Manual 1173 9357 02 06 152 R amp SS9FSW K91 Remote Commands for WLAN Measurements PEE CC C t Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance TRIGger SEQuenceJ LEVel EXTernal port eec nns 154 TRIGger SEQuence EEVel IFPOWE TEE 155 TRIGger SEQuence E EVel IGIPOWet cierre eere cnt ii eee gero eee Tear e ee ERAN een 155 TRIGger SEQuence LEVelEPOW6erAU TO iieri dorthin a EEN 155 TRIGgerL SEQuence E EVel REPOWOE TT 156 TRiGger SEQuence SLOP EE 156 TRIGGESH edze h dpj l 156 TRIGger SEQuence TIME RINTerval sess nen nene sns 157 TRIGger SEQuence DTIMe lt DropoutTime gt D
177. d defines the trigger hysteresis which is only available for IF Power trigger Sources Parameters lt Hysteresis gt Range 3 dB to 50 dB RST 3 dB Example TRIG SOUR IFP Sets the IF power trigger source TRIG IFP HYST 10DB Sets the hysteresis limit value Manual operation See Trigger Source Settings on page 85 See Hysteresis on page 89 TRIGger SEQuence LEVel BBPower Level This command sets the level of the baseband power trigger This command is available for the Digital Baseband Interface R amp S FSW B17 and the Analog Baseband Interface R amp S FSW B71 Parameters Level Range 50 dBm to 20 dBm RST 20 DBM Example TRIG LEV BB 30DBM TRIGger SEQuence LEVel EXTernal lt port gt lt TriggerLevel gt This command defines the level the external signal must exceed to cause a trigger event Note that the variable INPUT OUTPUT connectors ports 2 3 must be set for use as input using the OUTPut TRIGger lt port gt DIRection command For details on the trigger source see Trigger Source Settings on page 85 Suffix lt port gt 11213 Selects the trigger port 1 trigger port 1 TRIGGER INPUT connector on front panel 2 trigger port 2 TRIGGER INPUT OUTPUT connector on front panel 3 trigger port 3 TRIGGER3 INPUT OUTPUT connector on rear panel Parameters lt TriggerLevel gt Range 0 5V to 3 5V RST 1 4V Example TRIG LEV 2V ERREUR EA I T i e e A LLLLLLLLLLL
178. d specifies the start offset of the FFT for OFDM demodulation not for the FFT Spectrum display Parameters lt Mode gt AUTO GlCenter PEAK AUTO The FFT start offset is automatically chosen to minimize the inter symbol interference GlCenter Guard Interval Center The FFT start offset is placed to the center of the guard interval PEAK The peak of the fine timing metric is used to determine the FFT start offset RST AUTO Manual operation See FFT Start Offset on page 91 T User Manual 1173 9357 02 06 160 R amp SS9FSW K91 Remote Commands for WLAN Measurements HEEMETAMCIMOI T HPPr Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe DEMod TXARea State If enabled the R amp S FSW WLAN application initially performs a coarse burst search on the input signal in which increases in the power vs time trace are detected Further time consuming processing is then only performed where bursts are assumed This improves the measurement speed for signals with low duty cycle rates However for signals in which the PPDU power levels differ significantly this option should be disabled as otherwise some PPDUs may not be detected Parameters State ON OFF 0 1 ON 1 A coarse burst search is performed based on the power levels of the input signal OFF 0 No pre evalu
179. deducted For an ideal channel the phase increases linearly which causes a constant time delay over all carriers In this case a horizontal line at the zero value would be the result The numeric trace results for this evaluation method are described in chapter 9 9 4 7 Group Delay on page 218 Remote command LAY ADD 1 RIGH GDEL see LAYout ADD WINDow on page 186 or CONF BURS SPEC FLAT SEL GRD see CONFigure BURSt SPECtrum FLATness SELect on page 138 and CONFigure BURSt SPECtrum FLATness IMMediate on page 138 Magnitude Capture The Magnitude Capture Buffer display shows the complete range of captured data for the last sweep Green bars at the bottom of the Magnitude Capture Buffer display indicate the positions of the analyzed PPDUs E N User Manual 1173 9357 02 06 29 R amp S FSW K91 Measurements and Result Displays a SS WLAN UO Measurement Modulation Accuracy Flatness and Tolerance 1 Magnitude Capture Numeric trace results are not available for this evaluation method Remote command LAY ADD 1 RIGH CMEM See LAYout ADD WINDow on page 186 PLCP Header IEEE 802 11b g GSSS This result display shows the decoded data from the PLCP header of the PPDU This result display is only available for single carrier measurements IEEE 802 11b g DSSS for other standards use Signal Field instead 1 PLCP Header Signal PSDU Length 01101110 Mbit
180. demodulation range within a PPDU For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 UNIT EVM lt Unit gt This command specifies the units for EVM limits and results see chapter 3 1 1 Modu lation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Unit DB PCT RST DB UNIT GIMBalance Unit This command specifies the units for gain imbalance results see chapter 3 1 1 Modu lation Accuracy Flatness and Tolerance Parameters on page 13 Parameters lt Unit gt DB PCT RST DB Limit Check Results The following commands are required to query the results of the limit checks Useful commands for retrieving results described elsewhere e UNIT EVM on page 203 e UNIT GIMBalance on page 203 Remote commands exclusive to retrieving limit check results GALGulate le CART BE E EE 204 CAL Culate IMC DBURGCEVM AL LUIAVERaoel RE Gu 204 CAL Culate L IM BURGGCEVM ALL M Aximum RESGu 204 CALCulate LIMit BURStEVM DATA AVERage RESUIt eese 204 CAL Culate IM BURGGEVMDATAMAimum RESGuI 204 CAL Culatel IMC BURG EVM PI ot AVERaoelREGut eese 205 CAL Culate L IM BURG EVM Pi otM ANimum RE Gut 205 CAL Culatel IMC BURG EERbRor AVERaoel RE Gut 205 CAL Culate IM BURG EtERbRorMANimum RE Gul 205 User Manual 1173 9357 02 06 203 R amp SS9FSW K91 Remote Commands for WLAN Measurements c aa DV m
181. e Overview and dialog boxes are updated to indicate the settings for the selected window 5 3 3 Signal Description The signal description provides information on the expected input signal Signal Input Source Frequency Amplitude Output Signal Characteristic SCLC E IEEE 802 lla Frequency Cut EEUU 72 aig ENN 72 Standard Defines the WLAN standard The measurements are performed according to the speci fied standard with the correct limit values and limit lines Many other WLAN measurement settings depend on the selected standard see chap ter 4 5 Demodulation Parameters Logical Filters on page 60 Remote command CONFigure STANdard on page 141 Frequency Specifies the center frequency of the signal to be measured Remote command SENSe FREQuency CENTer on page 145 5 3 4 Input and Frontend Settings The R amp S FSW can analyze signals from different input sources and provide various types of output such as noise or trigger signals Importing and Exporting UO Data The I Q data to be analyzed for WLAN 802 11 can not only be measured by the WLAN application itself it can also be imported to the application provided it has the correct format Furthermore the analyzed UO data from the WLAN application can be exported for further analysis in external applications See chapter 5 3 13 Import Export Functions on page 114 User Manual 1173 9357 02 06 72 R amp S FSW K91 Configurati
182. e IQ STATe on page 220 Import Provides functions to import data IQ Import Import Opens a file selection dialog box to select an import file that contains IQ data This function is only available in single sweep mode and only in applications that process UO data such as the UO Analyzer or optional applications Note that the UO data must have a specific format as described in chapter A 2 I Q Data File Format iq tar on page 234 UO import is not available in MSRA mode For details see chapter 5 3 13 Import Export Functions on page 114 Remote command MMEMory LOAD IQ STATe on page 220 Frequency Sweep Measurements When you activate a measurement channel in WLAN mode an IQ measurement of the input signal is started automatically see chapter 3 1 WLAN UO Measurement Modu lation Accuracy Flatness and Tolerance on page 13 However some parameters specified in the WLAN 802 11 standard require a better signal to noise level or a smaller User Manual 1173 9357 02 06 114 R amp S FSW K91 Configuration a A Aa Frequency Sweep Measurements bandwidth filter than the default measurement on UO data provides and must be deter mined in separate measurements based on RF data see chapter 3 2 Frequency Sweep Measurements on page 39 In these measurements demodulation is not performed Selecting the measurement type WLAN measurements require a special operating mode on the R
183. e WLAN 802 11 application for IEEE 802 11b or g DSSS signals Abbreviations timing offset At frequency offset Ao phase offset 6 estimate of the gain factor in the I branch da estimate of the gain factor in the Q branch Ada accurate estimate of the crosstalk factor of the Q branch in the I branch Rv estimated baseband filter of the transmitter Rv estimated baseband filter of the receiver l estimate of the IQ offset in the I branch 6a estimate of the IQ offset in the I branch r v measurement signal v estimate of the reference signal V estimate of the power normalized and undisturbed reference signal ARG calculation of the angle of a complex value EVM error vector magnitude User Manual 1173 9357 02 06 52 R amp S FSW K91 Measurement Basics 4 2 1 Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS IMAG calculation of the imaginary part of a complex value PPDU protocol data unit a burst in the signal containing transmission data PSDU protocol service data unit a burst in the signal containing service data REAL calculation of the real part of a complex value e Block Diagram for Single Carrier Measurements sess 53 e Calculation of Signal Patdtmmelere ciesescso netto dac daa 55 e Literature on the IEEE 802 11b Standard eene 58 Block Diagram f
184. e WLAN 802 11 standard set the Channel Estimation Range to Payload see Channel Esti mation Range on page 92 The channel estimation is performed in the preamble and the payload The EVM results can be calculated more accurately LEES User Manual 1173 9357 02 06 123 R amp S FSW K91 Optimizing and Troubleshooting the Measurement Error Messages and Warnings Accounting for phase drift in the EVM According to the WLAN 802 11 standards the common phase drift must be estimated and compensated from the pilots Thus these deviations are not included in the EVM To include the phase drift disable Phase Tracking see Phase Tracking on page 92 Analyzing time jitter Normally a symbol wise timing jitter is negligible and not required by the IEEE 802 11a measurement standard 6 and thus not considered in channel estimation However there may be situations where the timing drift has to be taken into account However to analyze the time jitter per symbol enable Timing Tracking see Timing Error Tracking on page 92 Compensating for non standard conform pilot sequences In case the pilot generation algorithm of the device under test DUT has a problem the non standard conform pilot sequence might affect the measurement results or the WLAN application might not synchronize at all onto the signal generated by the DUT In this case set the Pilots for Tracking to Detected see Pilots for Tracking on page 93
185. e of an additive white Gaussian noise AWGN channel the FFT is described by 4 5 common timing 1 Lk i N J phase phase r Kg X94 8 XA xe FFT 4 1 with Kj the modulation dependant normalization factor e ay the symbol of sub carrier k at symbol e g the gain at the symbol in relation to the reference gain g 1 at the long symbol LS e H the channel frequency response at the long symbol LS e phase n the common phase drift phase of all sub carriers at symbol see Common phase drift User Manual 1173 9357 02 06 47 R amp SS9FSW K91 Measurement Basics mum m CIN mM M M M ae Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM e phase n the phase of sub carrier k at symbol caused by the timing drift see Common phase drift e nj the independent Gaussian distributed noise samples Phase drift and frequency deviation The common phase drift in FFT is given by phasej 2nxN Nx Af rest Txl dy Common phase drift 4 2 with e N 80 the number of Nyquist samples of the symbol period N 64 the number of Nyquist samples of the useful part of the symbol A frest the not yet compensated frequency deviation e dY the phase jitter at the symbol In general the coarse frequency estimate Af coarse see figure 4 1 is not error free Therefore the remaining fr
186. e performed one after the other repeatedly regardless of the channel s sweep mode in the same order until the Sequencer is stopped CDEFined First a single sequence is performed Then only those channels in continuous sweep mode INIT CONT ON are repeated RST CONTinuous Example SYST SEQ ON Activates the Sequencer INIT SEQ MODE SING Sets single sequence mode so each active measurement will be performed once INIT SEQ IMM Starts the sequential measurements Manual operation See Sequencer Mode on page 67 SYSTem SEQuencer State This command turns the Sequencer on and off The Sequencer must be active before any other Sequencer commands INIT SEQ are executed otherwise an error will occur A detailed programming example is provided in the Operating Modes chapter in the R amp S FSW User Manual I User Manual 1173 9357 02 06 196 R amp S9FSW K91 Remote Commands for WLAN Measurements Retrieving Results Parameters State ON OFF 0 1 ON 1 The Sequencer is activated and a sequential measurement is started immediately OFF 0 The Sequencer is deactivated Any running sequential measure ments are stopped Further Sequencer commands INIT SEQ are not available RST 0 Example SYST SEQ ON Activates the Sequencer INIT SEQ MODE SING Sets single Sequencer mode so each active measurement will be performed once INIT SEQ IMM Starts the sequential me
187. e time trigger User Manual 1173 9357 02 06 157 R amp SS9FSW K91 Remote Commands for WLAN Measurements NEMO X Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters Interval 2 0 ms to 5000 Range 2ms to 5000s RST 1 0s Example TRIG SOUR TIME Selects the time trigger input for triggering TRIG TIME RINT 50 The sweep starts every 50 s Manual operation See Trigger Source Settings on page 85 See Repetition Interval on page 88 Configuring the Trigger Output The following commands are required to send the trigger signal to one of the variable TRIGGER INPUT OUTPUT connectors The tasks for manual operation are described in Trigger 2 3 on page 76 OUTPut TRIGger port DI Rection EE 158 OUTP t TRIGgereport EEVel cis cleri ira deese exeo ENEE ENNER aep dene ENKEN EE 158 OLUTPut PRIGSerepan s GK dE 159 OUTPut TRIGger port PULSe IMMediate ee ee eeeeeeee eise eene ennemi 159 OUTPut TRIGgersport PUES ENGIb 5 31 retten errabat ene RR haad 160 OUTPut TRIGger lt port gt DIRection Direction This command selects the trigger direction Suffix port 2 3 Selects the trigger port to which the output is sent 2 trigger port 2 front 3 trigger port 3 rear Parameters lt Direction gt INPut Port works as an input OUTPut Por
188. e windows The WLAN evaluation methods are described in chapter 3 Measurements and Result Dis plays on page 13 To close the SmartGrid mode and restore the previous softkey menu select the 2 Close icon in the righthand corner of the toolbar or press any key on the front panel o For details on working with the SmartGrid see the R amp S FSW Getting Started manual 5 3 WLAN IQ Measurement Modulation Accuracy Flat ness Tolerance When you activate the WLAN application an UO measurement of the input signal is star ted automatically with the default configuration The WLAN menu is displayed and pro vides access to the most important configuration functions This menu is also displayed when you press the MEAS CONFIG key on the front panel The Span Bandwidth Lines and Marker Functions menus are not available for WLAN IQ measurements WLAN measurements can be configured easily in the Overview dialog box which is displayed when you select the Overview softkey from any menu User Manual 1173 9357 02 06 68 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance e Default Settings for WLAN Measurements AAA 69 e Cohfgurauon OVeViIBW 3 e rnit ter vidit EE eI AE Eae eda 70 Signal Despli RP 72 e inputand Frontend Sellings rin rrt deine t Feier e haee ido 72 e Signal Capture Data ACquisIHOn 22irr toit etna aeter EE SEA 82 e Synchronizati
189. easurement Modulation Accuracy Flatness Tolerance Parameter Value Pilot tracking According to standard PPDU format Auto same type as first PPDU Channel bandwidth to measure Auto same type as first PPDU MCS to use Auto same type as first PPDU Evaluations Window 1 Magnitude Capture Window 2 Constellation 5 3 2 Configuration Overview NUN Throughout the measurement channel configuration an overview of the most important n currently defined settings is provided in the Overview The Overview is displayed when MEE you select the Overview icon which is available at the bottom of all softkey menus Overview 15 10 ys see WLAN Modulation Accuracy Spectral Flatness Center Frequency Tolerance Symbol Clock Tolerance Channel No Center Freq Chan Spacing Ref Level MIMO No Rx Power Interval Search MIMO No Tx Attenuation MIMO Capture FET Start Offset bg Synchronization Signal Description Input Frontend Signal Capture OFDM Demod Tracking Channel Evaluation ISS Estimation Range Display Config PPDU F PPDU Stat Coun Magnitude Capture CBW to mcs Meas based on Pilots Tracking STS Selection Spotial Mapping Steele a C 1 Magnitude Capture H The Overview not only shows the main measurement settings it also provides quick access to the main settings dialog boxes The indicated signal flow shows which param eters affect which processing stage in the measureme
190. ecision Channel equalizing for PPDU Length Detection fully and user compensated measure ment signal is not possible because the estimated channel matrix is singular to working precision User Manual 1173 9357 02 06 125 R amp SS9FSW K91 Remote Commands for WLAN Measurements Common Suffixes 9 Remote Commands for WLAN Measure ments The following commands are required to perform measurements in the R amp S FSW WLAN application in a remote environment It assumes that the R amp S FSW has already been set up for remote operation in a network as described in the base unit manual How to Set Up a Network and Remote Control Note that basic tasks that are independant of the application are not described here For a description of such tasks see the R amp S FSW User Manual In particular this includes e Managing Settings and Results i e storing and loading settings and result data e Basic instrument configuration e g checking the system configuration customizing the screen layout or configuring networks and remote operation e Using the common status registers After an introduction to SCPI commands the following tasks specific to the WLAN appli cation are described here e COMMON Olli EEN 126 WACO CMON EE 127 e Activating WLAN Measurements EE EEEENNEKESEREEEEEEREEEREEEEEREENNEEESEEEEEENNNEEeEE 132 Selecting a Measureribhil 2coe eroi ree eed cldeddeslivagenste de stveaeeeee ans ena dade cays 1
191. ectronic Attenuation Option B25 nere arde trie idee ia 81 inet poc e ess 82 L Preamplifier option B3 usse iueiai iinde iueiai 82 Reference Level Settings The reference level defines the expected maximum signal level Signal levels above this value may not be measured correctly which is indicated by the IF OVLD status display Reference Level Mode Reference Level Settings By default the reference level is automatically adapted to its optimal value for the current input data continuously At the same time the internal attenuators and the preamplifier are adjusted so the signal to noise ratio is optimized while signal compression clipping and overload conditions are minimized User Manual 1173 9357 02 06 79 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance In order to define the reference level manually switch to Manual mode In this case you must define the following reference level parameters Remote command CONF POW AUTO ON see CONFigure POWer AUTO on page 181 Reference Level Reference Level Settings Defines the expected maximum signal level Signal levels above this value may not be measured correctly which is indicated by the IF OVLD status display This value is overwritten if Auto Level mode is turned on Remote command DISPlay WINDowcn TRACe Y SCALe RLEVel on page 147 Signal Level RMS Ref
192. ed RF data However the required power information can be determined much more precisely as more noise is filtered out of the signal The Frequency sweep measurements provided by the R amp S FSW WLAN application are identical to the corresponding measurements in the base unit but are pre configured according to the requirements of the selected WLAN 802 11 standard For details on these measurements see the R amp S FSW User Manual The R amp S FSW WLAN application provides the following frequency sweep measure ments 3 2 1 Measurement Types and Results for Frequency Sweep Measure ments The R amp S FSW WLAN application provides the following pre configured frequency sweep measurements Channel Power AGLI neret ae tete dre etat cet EEN 39 opectrumiEmissiom eebe Sege re eia eed re ern debe ids deeg 40 OCCUPIED Ee EE 41 e 01s DM 42 Channel Power ACLR Channel Power ACLR performs an adjacent channel power also known as adjacent channel leakage ratio measurement according to WLAN 802 11 specifications The R amp S FSW measures the channel power and the relative power of the adjacent channels and of the alternate channels The results are displayed in the Result Summary I User Manual 1173 9357 02 06 39 R amp S FSW K91 Measurements and Result Displays REESEN Frequency Sweep Measurements Ref Level 7 36 dBm RBW 10 kHz 17dB SWT 100 ms s VBW 300 kHz Mode Aut CF 850 0 MHz 1001 pts 419 0 kHz Span 4 19 MHz 2 Result S
193. ed to FETCh BURSt COUNt Usage Query only FETCh SYMBol COUNt This command returns the number of symbols in each analyzed PPDU as a comma sep arated list The length of the list corresponds to the number of PPDUs i e the result of FETCh BURSt COUNt ALL I User Manual 1173 9357 02 06 198 R amp S FSW K91 Remote Commands for WLAN Measurements 9 9 1 2 Retrieving Results Usage Query only FETCh BURSt LENGths This command returns the length of the analyzed PPDUs from the current measurement If the number of PPDUs to analyze is greater than the number of PPDUs that can be captured in one buffer this command only returns the lengths of the PPDUs in the current capture buffer The result is a comma separated list of lengths one for each PPDU Return values lt PPDULength gt Length of the PPDU in symbols Usage Query only Error Parameter Results The following commands are required to retrieve individual results from the WLAN IQ measurement on the captured I Q data see chapter 3 1 1 Modulation Accuracy Flat ness and Tolerance Parameters on page 13 PE TCMB URS E epe M OREL 200 FETCHBURSCORESIAVERGJE KE 200 ai Deele dE len la EE 200 FETCH BURSECRE SEMINO EE 200 FETGCD BURSCEVMPALL AVEIRAQOT anite iia su REN SEENEN ENEE 200 FETCHEBURStCEVM ALL MAXIMUM 1 nara rien ENEE NNN tan nh Ri he pnr n Ra re neni na podran 200 FEUVGCIHEBURSEEVNMUALEMIBIRII 5 aa NEE NNN 200 FETCh BURSEEVM I
194. ee EVM vs Symbol on page 27 CONFigure BURSt PVT IMMediate This remote control command configures the measurement type to be Power vs Time CONFigure BURSt SPECtrum FFT IMMediate This remote control command configures the result display type of window 2 to be FFT Spectrum Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See FFT Spectrum on page 28 CONFigure BURSt SPECtrum FLATness SELect lt MeasType gt This remote control command configures result display type of window 2 to be either Spectrum Flatness or Group Delay Results are only displayed after a measurement is executed e g using the 1NTTiate IMMediate command Parameters lt MeasType gt FLATness GRDelay Example CONF BURS SPEC FLAT SEL FLAT Configures the result display of window 2 to be Spectrum Flatness CONF BURS SPEC FLAT IMM Performs a default WLAN measurement When the measurement is completed the Spectrum Flatness results are displayed Usage Event Manual operation See Group Delay on page 29 See Spectrum Flatness on page 38 CONFigure BURSt SPECtrum FLATness IMMediate This remote control command configures the result display in window 2 to be Spectrum Flatness or Group Delay depending on which result display was selected last using CONFigure BURSt SPECtrum FLATness SELect on page 138 Results are only displayed after a measurem
195. eeeeeees 142 PSDU Abbreviations oni rre aN 53 PvT Full PPDU result display sessssss 31 PvT Full Burst Trace data EE 219 Q Quadrature offset ssssssssssssssssseeeeeneennnnn 18 Izd Mm 14 R Reference level Auto level ree 81 112 Auto level continuous 79 Default Offset m ET 80 Offset softkey 80 LU FE sees 80 AUG Uode eh sete iL pn td ET 80 Remote commands Basics on syntax sssssss esee 127 Boolean values 131 Capitalization 128 Character data p 131 Data blocks 131 Numeric values 130 Obsolete 228 Optional keywords 129 Parameters 129 Strings 131 Suffixes 128 Repetition interval 88 Softkey s 88 Resetting RF input protection ssseeseeeeee 61 142 Restoring Channel settings ssssssse 71 Result configuration Scy ma 111 Result displays Bitstream s aesan ean EEEE 22 Configuration remote in 184 Configuring 68 Constellation 24 Constellation vs carrier Les wee 25 Diagram m ss 43 Evaluated data 108 EVM vs carrier 26 EVM vs chip 27 EVM vs Symbol wall FFT spectrum ess 28 Group Delay m 2
196. eeesss 224 WEAN n PE 224 STBC PPDUS 2 nerit e Pre erg tet hod 99 106 PPDUS remote iere eie e 166 Suffixes COMMON E aii Remote commands s Swap Q MET acce 151 Sweep ADOMING E 113 Configuration remote usse 183 Configuration softkey ssssssssssss 113 User Manual 1173 9357 02 06 Index Mime remote E 152 Symbol clock 14 Error limit check result remote 205 error limit remote esee 180 Symbols Count remote 1 ect teet aii 198 Data sa Long IEEE 802 11a g OFDM neccen 46 Short IEEE 802 11a g OFDM sssssss 46 Synchronization 2 Remote control neret 160 T Time trigger Repetition interval nre 88 cuc m 87 Timing SOAS OY ci ee Detection IEEE 802 11a g OFDM Se RIIT EINEN EE Tracking Tracking IEEE 802 11a g OFDM Timing error tracking sese Tolerance Parameters ccceecceeeeeeeceeeeeceeeeaeeeeeeeeeeeteeneeeeeeeaee 13 Traces Queryirig Tesults rseson nnan D re tenen 22 Results remote etre tr cob cones 210 Trackin RE Default Level errors occi eret ster hier iiSi 93 162 Phase ON ect ooo erat heehee dads 92 162 Pilots Remote contra 161
197. eep Measurements on WLAN Signals The R amp S FSW WLAN application uses the functionality of the FSW base system Spec trum application see the R amp S FSW User Manual to perform the WLAN frequency sweep measurements The R amp S FSW WLAN application automatically sets the parameters to predefined settings as described in chapter 5 4 Frequency Sweep Measurements on page 114 The WLAN RF measurements must be activated for a measurement channel in the WLAN application see chapter 9 3 Activating WLAN Measurements on page 132 For details on configuring these RF measurements in a remote environment see the Remote Commands chapter of the R amp S FSW User Manual Configuring the Result Display The following commands are required to configure the screen display in a remote envi ronment The corresponding tasks for manual operation are described in chapter 5 2 Display Configuration on page 68 The suffix n in the following remote commands represents the window 1 16 in the currently selected measurement channel General Window EES seed EEN Fase ne 184 e Working with Windows in the Display 185 e Selecting Items to Display in Result Summary eene 191 General Window Commands The following commands are required to configure general window layout independant of the application EE User Manual 1173 9357 02 06 184 R amp SS9FSW K91 Remote Commands for WLAN Measurements Configuring the Res
198. eep RUN CONT While the measurement is running the Continuous Sweep softkey and the RUN CONT key are highlighted The running measurement can be aborted by selecting the highlighted softkey or key again The results are not deleted until a new measurement is started Note Sequencer If the Sequencer is active the Continuous Sweep softkey only con trols the sweep mode for the currently selected channel however the sweep mode only has an effect the next time the Sequencer activates that channel and only for a channel defined sequence In this case a channel in continuous sweep mode is swept repeatedly Furthermore the RUN CONT key on the front panel controls the Sequencer not individ ual sweeps RUN CONT starts the Sequencer in continuous mode Remote command INITiate CONTinuous on page 194 Single Sweep RUN SINGLE While the measurement is running the Single Sweep softkey and the RUN SINGLE key are highlighted The running measurement can be aborted by selecting the highligh ted softkey or key again Note Sequencer If the Sequencer is active the Single Sweep softkey only controls the sweep mode for the currently selected channel however the sweep mode only has an effect the next time the Sequencer activates that channel and only for a channel defined sequence In this case a channel in single sweep mode is swept only once by the Sequencer Furthermore the RUN SINGLE key on the front panel controls the Sequencer no
199. efines the time the input signal must stay below the trigger level before a trigger is detected again Parameters lt DropoutTime gt Dropout time of the trigger Range O sto 10 0s RST 0s Manual operation See Trigger Source Settings on page 85 See Drop Out Time on page 88 TRIGger SEQuence HOLDoff TIME Offset Defines the time offset between the trigger event and the start of the sweep data cap turing Parameters Fels RST 0s Example TRIG HOLD 500us Manual operation See Trigger Source Settings on page 85 See Trigger Offset on page 88 TRIGger SEQuence IFPower HOLDoff Period This command defines the holding time before the next trigger event Note that this command can be used for any trigger source not just IF Power despite the legacy keyword Parameters Period Range Os to 10s RST 0s Example TRIG SOUR EXT Sets an external trigger source TRIG IFP HOLD 200 ns Sets the holding time to 200 ns Manual operation See Trigger Source Settings on page 85 See Trigger Holdoff on page 89 ERREUR RI M User Manual 1173 9357 02 06 153 R amp SS9FSW K91 Remote Commands for WLAN Measurements HAEC X C ni H m Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance TRIGger SEQuence IFPower HYSTeresis lt Hysteresis gt This comman
200. egardless of their visibility on the screen The Result Configuration softkey in the main WLAN menu opens the Result Configu ration dialog box This softkey is only available if a window with a Result Summary Detailed or Result Summary Global result display is displayed This window must be focussed or you must select it from the Specifics for selection list in the Overview IEEE 802 1 m1 Result Summary Global Items Pilot Bit Error EVM All Carriers EVM Data Carriers EVM Pilot Carriers Center Frequency Error Symbol Clock Error UECHT gt Result Summary Global z Fig 5 6 Result Summary Global configuration for IEEE 802 11a g OFDM standards Remote command DISPlay WINDow lt n gt TABLe ITEM on page 192 5 3 11 Automatic Settings Some settings can be adjusted by the R amp S FSW automatically according to the current measurement settings and signal characteristics Ee User Manual 1173 9357 02 06 111 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance To activate the automatic adjustment of a setting select the corresponding function in the AUTO SET menu or in the configuration dialog box for the setting where available Setting the Reference Level Automatically Auto Level esses 112 Resetting the Automatic Measurement Time Meastime Auto 112 Changing the Automat
201. electing a Common RF Measurement for WLAN Signals The following commands are required to select a common RF measurement for WLAN signals in a remote environment For details on available measurements see chapter 3 2 Frequency Sweep Measure ments on page 39 I User Manual 1173 9357 02 06 139 R amp S9FSW K91 Remote Commands for WLAN Measurements Selecting a Measurement The selected measurement must be started explicitely see chapter 9 8 Starting a Mea surement on page 193 CONFigure BURSt SPECtrum ACPR IMMediate esee 140 CONFloure BURG GE CirumMAGkl JMMedatel nne eseeoeorosrrrrerererororsrrrnrnrenene 140 CONFloure BURG GP Cirum OBVWidt MMedlatel 140 CONFloure BURG GSTATsttceCCDFTlMMediatel sre seeosorssnrerenenererorsrnsnnerenene 140 CONFigure BURSt SPECtrum ACPR IMMediate This remote control command configures the result display in window 2 to be ACPR adjacent channel power relative Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See Channel Power ACLR on page 39 CONFigure BURSt SPECtrum MASK IMMediate This remote control command configures the result display in window 2 to be Spectrum Mask Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See Spectrum Emission Mask on page 40 CONFigure
202. ements CALCulate n MARKer me STATe uiia ctt titer dera tenu aka unen dean ac EE 221 CGALGulatespnsMARKersiWs E 221 CALCulate lt n gt MARKer lt m gt STATe State This command turns markers on and off If the corresponding marker number is currently active as a deltamarker it is turned into a normal marker Parameters State ON OFF RST OFF Example CALC MARK3 ON Switches on marker 3 CALCulate lt n gt MARKer lt m gt Y This command queries the position of a marker on the y axis If necessary the command activates the marker first LLL T e A LLLLLLLLLL L AALALIIILL AXX User Manual 1173 9357 02 06 221 R amp S9FSW K91 Remote Commands for WLAN Measurements EMG GG C UEUM MI c P se nage Analysis To get a valid result you have to perform a complete measurement with synchronization to the end of the measurement before reading out the result This is only possible for single sweeps See also INI Tiate CONTinuous on page 194 Return values Result Example Usage Manual operation Result at the marker position INIT CONT OFF Switches to single measurement mode CALC MARK2 ON Switches marker 2 INIT WAI Starts a measurement and waits for the end CALC MARK2 Y Outputs the measured value of marker 2 Query only See CCDF on page 42 See
203. ent is executed e g using the TNTTiate TMMediate command I User Manual 1173 9357 02 06 138 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 4 2 Selecting a Measurement Example CONF BURS SPEC FLAT SEL FLAT Configures the result display of window 2 to be Spectrum Flatness CONF BURS SPEC FLAT IMM Performs a default WLAN measurement When the measurement is completed the Spectrum Flatness results are displayed Usage Event Manual operation See Group Delay on page 29 See Spectrum Flatness on page 38 CONFigure BURStSTATistics BSTReam IMMediate This remote control command configures the result display type of window 2 to be Bit stream Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See Bitstream on page 22 CONFigure BURStSTATistics SFleld IMMediate This remote control command configures the result display type of window 2 to be Signal Field Results are only displayed after a measurement is executed e g using the INITiate IMMediate command Usage Event Manual operation See PLCP Header IEEE 802 11b g GSSS on page 30 See Signal Field on page 35 DISPlay WINDow lt n gt SELect This command sets the focus on the selected result display window This window is then the active window Example DISP WIND1 SEL Sets the window 1 active Usage Setting only S
204. ent of the level the R amp S FSW WLAN application nor malizes the EVM values Thus an EVM of 100 indicates that the error power on the I or Q channels equals the mean power on the I or Q channels respectively The peak vector error is the maximum EVM over all payload symbols and all active car riers for one PPDU If more than one PPDU is analyzed several analyzed PPDUS in the capture buffer or due to the PPDU Statistic Count No of PPDUs to Analyze setting the Min Mean Max columns show the minimum mean or maximum Peak EVM of all ana lyzed PPDUs The IEEE 802 11b or g DSSS standards allow a peak vector error of less than 35 In contrary to the specification the R amp S FSW WLAN application does not limit the mea surement to 1000 chips length but searches the maximum over the whole PPDU 3 1 2 Evaluation Methods for WLAN IQ Measurements The captured UO data from the WLAN signal can be evaluated using various different methods without having to start a new measurement or sweep Which results are dis played depends on the selected evaluation User Manual 1173 9357 02 06 21 R amp S FSW K91 Measurements and Result Displays a a es WLAN UO Measurement Modulation Accuracy Flatness and Tolerance The selected evaluation method not only affects the result display in a window but also the results of the trace data query in remote control see TRACe lt n gt DATA on page 210 All evaluations available for the se
205. equency error Af represents the frequency deviation in r not yet compensated Consequently the overall frequency deviation of the device under test DUT is calculated by Af AF coarse Afrest The common phase drift in Common phase drift is divided into two parts to calculate the overall frequency deviation of the DUT The reason for the phase jitter dy in Common phase drift may be different The nonlinear part of the phase jitter may be caused by the phase noise of the DUT oscillator Another reason for nonlinear phase jitter may be the increase of the DUT amplifier temperature at the beginning of the PPDU Note that besides the nonlinear part the phase jitter dy also contains a constant part This constant part is caused by the frequency deviation A frest not yet compensated To understand this keep in mind that the measurement of the phase starts at the first symbol 1 of the payload In contrast the channel frequency response H in FFT represents the channel at the long symbol of the preamble Conse quently the frequency deviation A frest not yet compensated produces a phase drift between the long symbol and the first symbol of the payload Therefore this phase drift appears as a constant value DC value in dY Tracking the phase drift timing jitter and gain Referring to the IEEE 802 11a g OFDM measurement standard chapter 17 3 9 7 Transmit modulation accuracy test 6 the common phase drift phase c nmo
206. er AUTO lt State gt This command is used to switch on or off automatic level detection When switched on level detection is performed prior to each UO data capture or measurement sweep The length of the sweep performed to determine the ideal reference level is defined by CONFigure POWer AUTO SWEep TIME on page 181 Parameters for setting and query State OFF Switches the auto level detection function off ON Switches the auto level detection function on ONCE Performs an auto level measurement once immediately RST ON Manual operation See Reference Level Settings on page 79 See Reference Level Mode on page 79 CONFigure POWer AUTO SWEep TIME Value This command is used to specify the auto track time i e the sweep time for auto level detection This setting can currently only be defined in remote control not in manual operation Parameters for setting and query Value numeric value Auto level measurement sweep time Range 0 01 to 1 RST Dis Default unit S Example CONF POW AUTO SWE TIME 0 01 MS SENSe ADJust CONF igure DURation Duration In order to determine the ideal reference level the R amp S FSW performs a measurement on the current input data This command defines the length of the measurement if SENSe ADJust CONFigure DURation MODE is set to MANual ERREUR EA N User Manual 1173 9357 02 06 181 R amp SS9FSW K91 Remote Commands for WLAN Measurements AER
207. er than Auto Remote command SENSe DEMod FORMat BCONtent AUTO on page 170 PPDU Format to measure Defines which PPDU formats are to be included in the analysis Depending on which standards the communicating devices are using different formats of PPDUs are availa ble Thus you can restrict analysis to the supported formats Note The PPDU format determines the available channel bandwidths For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 User Manual 1173 9357 02 06 94 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display Format column see Signal Field on page 35 Auto same type as first PPDU A1st The format of the first valid PPDU is detected and subsequent PPDUs are analyzed only if they have the same format Auto individually for each PPDU AI All PPDUs are analyzed regardless of their format Meas only M Only PPDUs with the specified format are analyzed Demod all as D All PPDUs are assumed to have the specified PPDU format Remote command SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 SENSe DEMod FORMat BANalyze on page 168 Channel Bandwidth to measure CBW Defines the channel band
208. erence Level Settings Specifies the mean power level of the source signal as supplied to the instrument s RF input This value is overwritten if Auto Level mode is turned on Remote command CONFigure POWer EXPected RF on page 147 Shifting the Display Offset Reference Level Settings Defines an arithmetic level offset This offset is added to the measured level irrespective of the selected unit The scaling of the y axis is changed accordingly Define an offset if the signal is attenuated or amplified before it is fed into the R amp S FSW so the application shows correct power results All displayed power level results will be shifted by this value Note however that the Reference Level value ignores the Reference Level Offset It is important to know the actual power level the R amp S FSW must handle To determine the required offset consider the external attenuation or gain applied to the input signal A positive value indicates that an attenuation took place R amp S FSW increa ses the displayed power values a negative value indicates an external gain R amp S FSW decreases the displayed power values The setting range is 200 dB in 0 01 dB steps Remote command DISPlay WINDowcn TRACe Y SCALe RLEVel OFFSet on page 148 Unit Reference Level Settings The R amp S FSW measures the signal voltage at the RF input In the default state the level is displayed at a power of 1 mW dBm Via the known input i
209. erval length long DL Remote command CONFigure WLAN GTIMe AUTO on page 164 CONFigure WLAN GTIMe AUTO TYPE on page 164 CONFigure WLAN GTIMe SELect on page 165 5 3 8 3 Demodulation IEEE 802 11b g DSSS The following settings are available for demodulation of IEEE 802 11b or g DSSS sig nals User Manual 1173 9357 02 06 101 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance A A p 5 gt P Demodulation Um Demodulatton PPDUs to Analyze pier ra EOT Meas only the specified PPDU Format e Trt ETC Meas only the specified PSDU Modulation PPDU Format Long PPDU PSDU Modulation SERVICE LENGTH CRC B bits 16 bits 16 bits Long PPDU Format Fig 5 3 Demodulation settings for IEEE 802 11b g DSSS signals PPDU Format to measure PSDU Modulation to use een 102 PPDU FOSU EE 103 PSDU Modula TEE 103 PPDU Format to measure PSDU Modulation to use Defines which PPDU formats modulations are to be included in the analysis Depending on which standards the communicating devices are using different formats of PPDUs are available Thus you can restrict analysis to the supported formats Note The PPDU format determines the available channel bandwidths For details on supported PPDU formats modulations and channel bandwidths depend ing on the standard see table 4 1 Auto same type as first PPDU The format modulation of the fir
210. es the center frequency step size You can increase or decrease the center frequency quickly in fixed steps using the SENS FREQ UP AND SENS FREQ DOWN commands see SENSe FREQuency CENTer on page 145 Parameters lt StepSize gt fmax iS specified in the data sheet Range 1 to fMAX RST 0 1 x span Default unit Hz Example FREQ CENT 100 MHz FREQ CENT STEP 10 MHz FREQ CENT UP Sets the center frequency to 110 MHz Manual operation See Center Frequency Stepsize on page 77 SENSe FREQuency CENTer STEP AUTO State This command couples or decouples the center frequency step size to the span E T User Manual 1173 9357 02 06 145 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 5 3 2 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters State ON OFF 0 1 RST 1 Example FREQ CENT STEP AUTO ON Activates the coupling of the step size to the span SENSe FREQuency OFFSet lt Offset gt This command defines a frequency offset If this value is not O Hz the application assumes that the input signal was frequency shifted outside the application All results of type frequency will be corrected for this shift numerically by the application See also Frequency Offset on page 78 Note In MSRA mode the setting command is only available for the MSRA Master For MSRA applic
211. ety information is also included The Getting Started manual in various languages is also available for download from the R amp S website on the R amp S FSW product page at http www2 rohde schwarz com prod uct FSW html User Manuals User manuals are provided for the base unit and each additional software option The user manuals are available in PDF format in printable form on the Documentation CD ROM delivered with the instrument In the user manuals all instrument functions are described in detail Furthermore they provide a complete description of the remote con trol commands with programming examples The user manual for the base unit provides basic information on operating the R amp S FSW in general and the Spectrum application in particular Furthermore the software func tions that enhance the basic functionality for various applications are described here An introduction to remote control is provided as well as information on maintenance instru ment interfaces and troubleshooting In the individual application manuals the specific instrument functions of the application are described in detail For additional information on default settings and parameters refer to the data sheets Basic information on operating the R amp S FSW is not included in the application manuals All user manuals are also available for download from the R amp S website on the R amp S FSW product page at http www2 rohde schwarz com product
212. f the UO parameter XML file must comply with the XML schema RsIqTar xsd available at http www rohde schwarz comf file RsIqTar xsd In particular the order of the XML elements must be respected i e iq tar uses an ordered XML schema For your own implementation of the iq tar file format make sure to validate your XML file against the given schema The following example shows an UO parameter XML file The XML elements and attrib utes are explained in the following sections Sample UO parameter XML file xyz xml lt xml version 1 0 encoding UTF 8 gt xml stylesheet type text xsl href open IqTar xml file in web browser xslt RS IQ TAR FileFormat fileFormatVersion 1 xsi noNamespaceSchemaLocation RsIqTar xsd xmlns xsi http www w3 org 2001 XMLSchema instance lt Name gt FSV K10 lt Name gt lt Comment gt Here is a comment lt Comment gt DateTime 2011 01 24T14 02 49 DateTime lt Samples gt 68751 lt Samples gt lt Clock unit Hz gt 6 5e 006 lt Clock gt T User Manual 1173 9357 02 06 235 R amp S9FSW K91 Annex Reference UO Data File Format iq tar lt Format gt complex lt Format gt lt DataType gt float32 lt DataType gt lt ScalingFactor unit V gt 1 lt ScalingFactor gt lt NumberOfChannels gt 1 lt NumberOfChannels gt DataFilename xyz complex float32 DataFilename lt UserData gt lt UserDefinedElement gt Example lt UserDefinedElement gt lt User
213. f the parameters the sequence r is compensated in the compensation blocks In the upper analyzing branch the compensation is user defined i e the user determines which of the parameters are compensated This is useful in order to extract the influence of these parameters The resulting output sequence is described by y s Data symbol estimation In the lower compensation branch the full compensation is always performed This sep arate compensation is necessary in order to avoid symbol errors After the full compen sation the secure estimation of the data symbols 4 is performed From FFT it is clear that first the channel transfer function H must be removed This is achieved by dividing the known coarse channel estimate HS calculated from the LS Usually an error free estimation of the data symbols can be assumed ee User Manual 1173 9357 02 06 50 R amp SS9FSW K91 Measurement Basics PREGA COD 1222 G Hg Un M Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM Improving the channel estimation In the next block a better channel estimate HL of the data and pilot sub carriers is calculated by using all nof symbols symbols of the payload PL This can be accom plished at this point because the phase is compensated and the data symbols are known The long observation interval of nof symbols symbols compared to the short interv
214. ference level and reference level offset e Analysis bandwidth e Number of samples User Manual 1173 9357 02 06 118 6 QD Analysis General result analysis settings concerning the trace and markers etc are currently not available for the standard WLAN measurements Only one Clear Write trace and one marker are available for these measurements Analysis of frequency sweep measurements General result analysis settings concerning the trace markers lines etc for RF meas urements are identical to the analysis functions in the Spectrum application except for some special marker functions and spectrograms which are not available in the WLAN application For details see the Common Analysis and Display Functions chapter in the R amp S FSW User Manual The remote commands required to perform these tasks are described in chapter 9 10 Analysis on page 221 R amp S FSW K91 How to Perform Measurements in the WLAN Application How to Determine Modulation Accuracy Flatness and Tolerance Parameters for WLAN Signals 7 Howto Perform Measurements in the WLAN Application The following step by step instructions demonstrate how to perform measurements in the R amp S FSW WLAN application The following tasks are described e How to Determine Modulation Accuracy Flatness and Tolerance Parameters for IF ESI c 120 e How to Determine the OBW SEM ACLR or CCDF for WLAN Signals 121
215. g is then only performed where bursts are assumed This improves the measurement speed for signals with low duty cycle rates However for signals in which the PPDU power levels differ significantly this option should be disabled as otherwise some PPDUs may not be detected Remote command SENSe DEMod TXARea on page 161 FFT Start Offset This command specifies the start offset of the FFT for OFDM demodulation not for the FFT Spectrum display AUTO The FFT start offset is automatically chosen to minimize the intersymbol interference Guard Interval Cntr Guard Interval Center The FFT start offset is placed to the center of the guard interval Peak The peak of the fine timing metric is used to determine the FFT start offset Remote command SENSe DEMod FFT OFFSet on page 160 5 3 7 Tracking and Channel Estimation The channel estimation settings determine which channels are assumed in the input sig nal Tracking settings allow for compensation of some transmission effects in the signal see Tracking the phase drift timing jitter and gain on page 48 User Manual 1173 9357 02 06 91 R amp S9 FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Channel Estimation L0 THIS Bs UH EIU GHI Preamble Tracking Tracking for the signal to be measured Phase Timing Off Level Off Of cera Ne According to Standard s Channel Estimation Rage TE
216. ger output The R amp S FSW can send output to another device either to pass on the internal trigger signal or to indicate that the R amp S FSW itself is ready to trigger The trigger signal can be output by the R amp S FSW automatically or manually by the user If itis sent automatically a high signal is output when the R amp S FSW has triggered due to a sweep start Device Triggered or when the R amp S FSW is ready to receive a trigger signal after a sweep start Trigger Armed Manual triggering If the trigger output signal is initiated manually the length and level high low of the trigger pulse is also user definable Note however that the trigger pulse level is always opposite to the constant signal level defined by the output Level setting e g for Level High a constant high signal is output to the connector until the Send Trigger button is selected Then a low pulse is sent Providing trigger signals as output is described in detail in the R amp S FSW User Manual Preparing the R amp S FSW for the Expected Input Signal Frontend Parameters On the R amp S FSW the input data can only be processed optimally if the hardware settings match the signal characteristics as closely as possible On the other hand the hardware must be protected from powers or frequencies that exceed the allowed limits Therefore you must set the hardware so that it is optimally prepared for the expected input signal without being overl
217. ger source by the R amp S FSW No further trigger parameters are available for the connec tor Output The R amp S FSW sends a trigger signal to the output connector to be used by connected devices Further trigger parameters are available for the connector Remote command OUTPut TRIGger lt port gt LEVel on page 158 OUTPut TRIGger lt port gt DIRection on page 158 Output Type Trigger 2 3 Type of signal to be sent to the output Device Trig Default Sends a trigger when the R amp S FSW triggers gered Trigger Sends a high level trigger when the R amp S FSW is in Ready for trig Armed ger state This state is indicated by a status bit in the STATus OPERation reg ister bit 5 as well as by a low level signal at the AUX port pin 9 User Defined Sends a trigger when user selects Send Trigger button In this case further parameters are available for the output signal Remote command OUTPut TRIGger lt port gt OTYPe on page 159 Level Output Type lt Trigger 2 3 Defines whether a constant high 1 or low 0 signal is sent to the output connector Remote command OUTPut TRIGger lt port gt LEVel on page 158 Pulse Length Output Type Trigger 2 3 Defines the length of the pulse sent as a trigger to the output connector Remote command OUTPut TRIGger lt port gt PULSe LENGth on page 160 EE User Manual 1173 9357 02 06 76 R amp S FSW K91 Configuration a
218. gnal you can define a hysteresis This setting defines an upper threshold the signal must exceed compared to the last mea surement before the reference level is adapted automatically Remote command SENSe ADJust CONFigure HYSTeresis UPPer on page 183 Lower Level Hysteresis When the reference level is adjusted automatically using the Auto Level function the internal attenuators and the preamplifier are also adjusted In order to avoid frequent adaptation due to small changes in the input signal you can define a hysteresis This setting defines a lower threshold the signal must fall below compared to the last mea surement before the reference level is adapted automatically Remote command SENSe ADJust CONFigure HYSTeresis LOWer on page 182 EEUU RI N User Manual 1173 9357 02 06 112 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance 5 3 12 Sweep Settings The sweep settings define how the data is measured eso T M 113 Continuous Sweep RUN CONT ccccssssscccecsssscccecceessssceeeceeessseceeceeeessseceeeeessseees 113 Single Sweep RUN SINGLE EE 113 Continue Single SWE 2 rette tetuer eres zuzt eere n anna Yn eR R REN R REA AR ZEN EN RER AA REN e RERO 113 Sweep Count This setting is currently ignored For statistical evaluation see PPDU Statistic Count No of PPDUs to Analyze on page 109 Continuous Sw
219. guring cdma2000 sss 118 see ACLR RM 39 Results oseere ss 42 Adjacent channels Trace data s 216 Filtering out essssseseeeeeenntentnnnntnne 84 151 Center frequency sss md Amplitude Default 69 Configuration remote seseeeeneeee 146 Error ss 14 Configuration softkey sss 78 Softkey e m es TT Settings sssssssss essere 78 Step size aipa i T EA 77 Analysis Channel Bandwidth definition sees 230 Estimating NENNEN Remote control mc Estimating IEEE 802 11a g OFDM RF measurements ccccccccsceceseceseesesescesesceseeeees 119 Channel bandwidth CBW Settings o ceccccccccccccecsscscscsseses cocseeecscsacsesecseseescscseesees 119 Default Applications PPDU Adopted parameters cccccccccccssseecesesecsssecsesseeeaeees 68 Channel bar Switching Displayed information sssssssssssss 10 Attenuation 2 M Channel defined Sequencer EE le 67 Default eeccececeseseesceceeeeesesceseeeseeeeeeessseeeeeeeeeeeeeeas Channel estimation Electronic M Default ret idet endet de ER cd Rcs 69 Manual taea EEN Remote control itii ett idet isa cR reina 161 s 81 Channel power Protective ACLR see ACLR ees eee 39 Protective remote s s sssssisinieneisisiririrernininrsrnne 142 Channels Auto level Active Carel e 59 Hysteresis sssssssssss sete tenes AWGN IEEE
220. he following order average CF error max CF error average symbol clock error max symbol clock error average UO offset maxi mum UO offset average EVM all carriers max EVM all car riers gt average EVM data carriers max EVM data carriers average EVM pilots max EVM pilots CALCulate LIMit BURSt EVM ALL AVERage Limit CALCulate LIMit BURSt EVM ALL MAXimum Limit This command sets or queries the average or maximum error vector magnitude limit for all carriers as determined by the default WLAN measurement For details on the EVM results and the default WLAN measurement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Limit numeric value in dB Theunitfor the EVM parameters can be changed in advance using UNIT EVM on page 203 Default unit DB CALCulate LIMit BURSt EVM DATA AVERage Limit CALCulate LIMit BURSt EVM DATA MAXimum Limit This command sets or queries the average or maximum error vector magnitude limit for the data carrier determined by the default WLAN measurement For details on the EVM results and the default WLAN measurement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Limit numeric value in dB Theunitfor the EVM parameters can be changed in advance using UNIT EVM on page 203 Default unit DB CALCulate LIMit BURSt EVM PIL
221. he transmitterR amp S FSW and the DUT should be synchronized using an external reference See R amp S FSW User Manual gt Instrument setup gt External reference the limits can be changed via remote control not manually see chapter 9 5 9 Limits on page 178 in this case the currently defined limits are displayed here ERREUR RA N User Manual 1173 9357 02 06 14 R amp S FSW K91 Measurements and Result Displays a a a es WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Parameter Description Symbol clock error ppm Clock error between the signal and the sample clock of the R amp S FSW in parts per million ppm i e the symbol timing error the corresponding limits specified in the standard are also indicated If possible the transmitterR amp S FSW and the DUT should be synchronized using an external reference See R amp S FSW User Manual gt Instrument setup gt External reference UO offset dB Transmitter center frequency leakage relative to the total Tx channel power see chapter 3 1 1 1 UO Offset on page 17 Gain imbalance dB Amplification of the quadrature phase component of the signal relative to the amplification of the in phase component see chapter 3 1 1 2 Gain Imbal ance on page 17 Quadrature offset Deviation of the quadrature phase angle from the ideal 90 see chapter 3 1 1 3 Quadrature Offset on page 18 PPDU power dB
222. hen the signal level rises above 22 dBm Manual operation See Upper Level Hysteresis on page 112 SENSe ADJust LEVel This command initiates a single internal measurement that evaluates and sets the ideal reference level for the current input data and measurement settings This ensures that the settings of the RF attenuation and the reference level are optimally adjusted to the signal level without overloading the R amp S FSW or limiting the dynamic range by an S N ratio that is too small Example ADJ LEV Usage Event Manual operation See Setting the Reference Level Automatically Auto Level on page 112 Sweep Settings FS PE re ONE erriten iiai dianid annie iana 183 SENSe SWEep COUNt lt SweepCount gt This command defines the number of sweeps that the application uses to average traces In case of continuous sweeps the application calculates the moving average over the average count In case of single sweep measurements the application stops the measurement and cal culates the average after the average count has been reached T User Manual 1173 9357 02 06 183 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 6 9 7 9 7 1 Configuring Frequency Sweep Measurements on WLAN Signals Example SWE COUN 64 Sets the number of sweeps to 64 INIT CONT OFF Switches to single sweep mode INIT WAI Starts a sweep and waits for its end Usage SCPI confirmed Configuring Frequency Sw
223. iOn 1 meretrice e etes c nete Mica tuba LER d d d oneal 161 SENSe DEMOG FFET OFFSet inerte edd er teg octo da ge cha epe dep dpa pa per geo tpe dt de ee 160 SENSe DEMod FORMat BANalyze essere nennen nnne nen nne trnenne tnter enne 168 IEN Ge IDEMod FORMarBANalvze Bye 229 IEN Ge IDEMod FORMarCBANalvze Bfvbe AUTO TE 169 SENSe DEMod FORMat BANalyze DBYTes EQUAl seen nene enne 174 SENSe DEMod FORMat BANalyze DBYTes MAX essent 175 IEN Ge IDEMod FORMatrBANalvze DvTesMiN nennen emen nennen 175 SENSe DEMod FORMat BANalyze DURation EQUAl esee 175 SENSe DEMod FORMat BANalyze DURation MAX essent 176 SENSe DEMod FORMat BANalyze DURation MIN esee eene 176 SENSe DEMod FORMat BANalyze SYMBols EQUal esee 177 SENSe DEMod FORMat BANalyze SYMBols MAX essent 177 SENSe DEMod FORMat BANalyze SYMBols MIN eese enne 177 SENSe DEMod FORMat MCSindex IEN Ge IDEMod FORMatrMC indes MODE enat 170 SENS DEMOd FORMAatNSTSITIQOX 5 netta cette ed rete t e eroe ee HE ER hai ene 171 SENSe DEMod FORMat NSTSindex MODE enne eene ener nre 171 IEN Ge IDEMod FORMat BCONientt AUTO 170 IEN Ge IDEMod TXAbea nennen nre nne nnne nennt nre ter erret erret nenne tn erret n nnne rre 161 REEL RE a User Manual 1173 9357 02 06 245 SENS FREQUENCY GCEN Mam
224. ia 179 CALCulate LIMIt BURSEFERRor AVERage 2 4 ttti iniaa 180 CALOulate LIMit BURSt FERROor MAXimum eese eese eene nennen nennen nennen nnn nnn 180 CALCulate LIMIit BURSt IQOFfset AVERage ueeeeeeseeeiicsesese eene nn nnns tni 180 CALCulate LIMit iBURSCtIQOFfset MAXImUIm ee oa saeua on unn nna annii nna iiaa 180 CALOCulate LIMit BURSt SYMBolerror AVERage eese 180 CALCulate LIMIEBURSES YMBolerrorMAXIEUE 25 2 22d at uas tnu tae tu ur ze nne a ct nn 180 CALCulate LIMit BURSt ALL Limits This command sets or returns the limit values for the parameters determined by the default WLAN measurement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 all in one step To define individual limit values use the individual CALCulate lt n gt LIMit lt k gt BURSt commands Note that the units for the EVM and gain imbalance parameters must be defined in advance using the following commands User Manual 1173 9357 02 06 178 R amp SS9FSW K91 Remote Commands for WLAN Measurements PEE CC C 7FT7 M C e n Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance e UNIT EVM on page 203 e UNIT GIMBalance on page 203 Parameters Limits The parameters are input or output as a list of ASCII values sep arated by in t
225. ic Measurement Time Meastime Manual 112 Upper Level Hvsteresis E 112 Lower Level FlysIelesis ccccecroindteeoe rtt aee cte EEGENEN 112 Setting the Reference Level Automatically Auto Level Automatically determines the optimal reference level for the current input data At the same time the internal attenuators and the preamplifier for analog baseband input the full scale level are adjusted so the signal to noise ratio is optimized while signal com pression clipping and overload conditions are minimized In order to do so a level measurement is performed to determine the optimal reference level Remote command SENSe ADJust LEVel on page 183 Resetting the Automatic Measurement Time Meastime Auto Resets the measurement duration for automatic settings to the default value Remote command SENSe ADJust CONFigure DURation MODE on page 182 Changing the Automatic Measurement Time Meastime Manual This function allows you to change the measurement duration for automatic setting adjustments Enter the value in seconds Remote command SENSe ADJust CONFigure DURation MODE on page 182 SENSe ADJust CONFigure DURation on page 181 Upper Level Hysteresis When the reference level is adjusted automatically using the Auto Level function the internal attenuators and the preamplifier are also adjusted In order to avoid frequent adaptation due to small changes in the input si
226. ich measurements are performed The currently selected mode softkey is highlighted blue During an active Sequencer process the selected mode soft key is highlighted orange Single Sequence Each measurement is performed once until all measurements in all active channels have been performed Continuous Sequence The measurements in each active channel are performed one after the other repeatedly in the same order until sequential operation is stop ped This is the default Sequencer mode User Manual 1173 9357 02 06 67 R amp S FSW K91 Configuration me 1 X J amp sx Yes Display Configuration Channel defined Sequence First a single sequence is performed Then only channels in continu ous sweep mode are repeated Remote command INITiate SEQuencer MODE on page 195 5 2 Display Configuration The measurement results can be displayed using various evaluation methods All eval uation methods available for the R amp S FSW WLAN application are displayed in the eval uation bar in SmartGrid mode when you do one of the following e Select the EJ SmartGrid icon from the toolbar e Select the Display Config button in the Overview e Select the Display Config softkey in any WLAN menu Then you can drag one or more evaluations to the display area and configure the layout as required Up to 16 evaluation methods can be displayed simultaneously in separat
227. iguration on page 68 To configure settings gt Select any button in the Overview to open the corresponding dialog box Select a setting in the channel bar at the top of the measurement channel tab to change a specific setting Preset Channel Select the Preset Channel button in the lower lefthand corner of the Overview to restore all measurement settings in the current channel to their default values Note that the PRESET key on the front panel restores all measurements in all mea surement channels on the R amp S FSW to their default values See chapter 5 3 1 Default Settings for WLAN Measurements on page 69 for details Remote command SYSTem PRESet CHANnel EXECute on page 135 Select Measurement Selects a measurement to be performed See Selecting the measurement type on page 66 Specifics for The measurement channel may contain several windows for different results Thus the settings indicated in the Overview and configured in the dialog boxes vary depending on the selected window Select an active window from the Specifics for selection list that is displayed in the Overview and in all window specific configuration dialog boxes ERREUR RA TN User Manual 1173 9357 02 06 71 R amp S9 FSW K91 Configuration mam w A n PRENNENT WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Th
228. index 01 0 OTOT 0 Channel 0 Complex sample 0 1 1 0 O 11I0 Channel 1 Complex sample 0 21 0 Q 2 0 Channel 2 Complex sample 0 01 11 Q 01 1 Channel 0 Complex sample 1 T t ODLITII Channel 1 Complex sample 1 2 1I 1 1 QI2 1 Channel 2 Complex sample 1 01 21 Q 0 2 Channel 0 Complex sample 2 VI 27 GTE 121 Channel 1 Complex sample 2 2 2 O21 2 Channel 2 Complex sample 2 Example Element order for complex cartesian data 1 channel This is an example of how to store complex cartesian data in float32 format using MAT LAB Save vector of complex cartesian I Q data i e iqiqiq N 100 iq randn 1 N 1j randn 1 N fid fopen xyz complex float32 w for k 1 length iq fwrite fid single real iq k float32 T User Manual 1173 9357 02 06 239 UO Data File Format iq tar fwrite fid single imag iq k float32 end fclose fid R amp S FSW K91 List of Remote Commands WLAN List of Remote Commands WLAN ABORD Ee ae oe 193 CAL Culate Mit ACbower ACHannel RE Gu 206 CAL Culatel IM AC Power Al Termate chzREGu eene 206 CALECulate EIMIEBURSEALL eut ter Tee rtr eo e ree eher rec recor aerae dyes d sued ede bee 178 CALCulate LIMIEBURSEALIERESUIE 2 ertt eret eee eere fpe aa echo edge 204 CAL Culate IM BURGCEVM ALL M
229. ing By default and when Using Electronic Attenuation Option B25 is not available mechanical attenuation is applied In Manual mode you can set the RF attenuation in 1 dB steps down to 0 dB also using the rotary knob Other entries are rounded to the next integer value The range is speci fied in the data sheet If the defined reference level cannot be set for the defined RF attenuation the reference level is adjusted accordingly and the warning Limit reached is displayed NOTICE Risk of hardware damage due to high power levels When decreasing the attenuation manually ensure that the power level does not exceed the maximum level allowed at the RF input as an overload may lead to hardware damage Remote command INPut ATTenuation on page 148 INPut ATTenuation AUTO on page 148 Using Electronic Attenuation Option B25 If option R amp S FSW B25 is installed you can also activate an electronic attenuator In Auto mode the settings are defined automatically in Manual mode you can define the mechanical and electronic attenuation separately Note Electronic attenuation is not available for stop frequencies or center frequencies in zero span gt 13 6 GHz In Auto mode RF attenuation is provided by the electronic attenuator as much as pos sible to reduce the amount of mechanical switching required Mechanical attenuation may provide a better signal to noise ratio however ERREUR RA T i LL 1 1 LL LL
230. ir individual Ness field contents corresponds to Auto individually for each PPDU MO M1 M2 M3 Only PPDUs with the specified Ness value are analyzed DO D1 D2 D3 All PPDUs are analyzed assuming the specified Ness value RST FBURst CONF WLAN EXT AUTO TYPE MO See Extension Spatial Streams sounding on page 107 CONFigure WLAN GTIMe AUTO lt State gt This remote control command specifies whether the guard time of the input signal is automatically detected or specified manually IEEE 802 11n or ac only Parameters lt State gt Manual operation ON The guard time is detected automatically according to CONFigure WLAN GTIMe AUTO TYPE on page 164 OFF The guard time is defined by the CONFigure WLAN GTIMe SELect command RST ON See Guard Interval Length on page 101 CONFigure WLAN GTIMe AUTO TYPE Type This remote control command specifies which PPDUS are analyzed depending on their guard length if automatic detection is used CONF WLAN GTIM AUTO ON see CONFigure WLAN GTIMe AUTO on page 164 This command is available for IEEE 802 11 n ac standards only User Manual 1173 9357 02 06 164 R amp S9FSW K91 Remote Commands for WLAN Measurements RNAEMECAMCIMUO COC M R ee ns Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Note On previous R amp
231. istics RESult lt t gt lt ResultType gt This command queries the results of a CCDF or ADP measurement for a specific trace Parameters lt ResultType gt MEAN Average RMS power in dBm measured during the measure ment time PEAK Peak power in dBm measured during the measurement time CFACtor Determined crest factor ratio of peak power to average power in dB ALL Results of all three measurements mentioned before separated by commas lt mean power gt lt peak power gt lt crest factor gt Example CALC STAT RES2 ALL Reads out the three measurement results of trace 2 Example of answer string 5 56 19 25 13 69 i e mean power 5 56 dBm peak power 19 25 dBm crest factor 13 69 dB Usage Query only Manual operation See CCDF on page 42 EST User Manual 1173 9357 02 06 209 R amp SS9FSW K91 Remote Commands for WLAN Measurements Retrieving Results 9 9 3 Retrieving Trace Results The following commands describe how to retrieve the trace data from the WLAN IQ measurement Modulation Accuracy Flatness and Tolerance Note that for these meas urements only 1 trace per window can be configured The traces for frequency sweep measurements are identical to those in the Spectrum application FORMat DATA Format This command selects the data format that is used for transmission of trace data from the R amp S FSW to the controlling computer Note that the command has no effect for data that you send to the
232. ive 01 data sequence with the scrambler disabled using DQPSK modulation A 100 kHz resolution bandwidth shall be used to perform this measurement Comparison to IQ offset measurement in the R amp S FSW WLAN application The IQ offset measurement in the R amp S FSW WLAN application returns the current carrier feedthrough normalized to the mean power at the symbol timings This measurement does not require a special test signal and is independent of the transmit filter shape The RF carrier suppression measured according to the standard is inversely proportional to the IQ offset measured in the R amp S FSW WLAN application The difference in dB between the two values depends on the transmit filter shape and should be determined with a reference measurement User Manual 1173 9357 02 06 19 R amp S FSW K91 Measurements and Result Displays REESEN WLAN UO Measurement Modulation Accuracy Flatness and Tolerance The following table lists the difference exemplarily for three transmit filter shapes 0 5 dB Transmit filter Q Offset dB RF Carrier Suppression dB Rectangular 11 dB Root raised cosine Q 0 3 10 dB Gaussian Q 0 3 9dB 3 1 1 5 EVM Measurement The R amp S FSW WLAN application provides two different types of EVM calculation PPDU EVM Direct method The PPDU EVM direct method evaluates the root mean square EVM over one PPDU That is the square root of the averaged error
233. ix n always refers to the window in the currently selected measure ment channel see INSTrument SELect on page 135 LAY GUEADDIEVVIN DOW ce TT 186 LAYout CATalog WINDOW noria aE EE EEA EAR 188 BAY cU DENUVEWINDGWI EEN 188 User Manual 1173 9357 02 06 185 R amp S FSW K91 Remote Commands for WLAN Measurements c Ee SS al Configuring the Result Display LAY outiREMove WINDOW 0 2 cccccccccnescececeesnsedeceecahenedeeeceentsceousdenaeecceterspenaedecetapeedacaeee 188 LAY OUEREPLace Me ET 189 BA Aue S PEIUS ele 189 LAYout WINDOW AS le EE 190 LAY out WINDowsms IDENUE ceto eere a ata aA aaa aaa 191 KEN Eelere edel 191 LAY out WINDOWSA REPLACE EE 191 LAYout ADD WINDow lt WindowName gt lt Direction gt lt WindowT ype gt This command adds a window to the display This command is always used as a query so that you immediately obtain the name of the new window as a result To replace an existing window use the LAYout REPLace WINDow command Parameters lt WindowName gt String containing the name of the existing window the new window is inserted next to By default the name of a window is the same as its index To determine the name and index of all active windows use the LAYout CATalog WINDow query lt Direction gt LEFT RIGHt ABOVe BELow Direction the new window is added relative to the existing window lt WindowType gt text value Type of result display e
234. kets 1 nof symbols 2 EVM gt m K moa X Ary nof symbols 43 Average error vector magnitude 4 8 This parameter is equivalent to the RMS average of all errors Errorgys of the IEEE 802 11a measurement commandment see 6 EET RU TR e e e L A 1 LLLLLLLLL LLLLLLIS User Manual 1173 9357 02 06 51 R amp SS9FSW K91 Measurement Basics Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS 4 1 2 Literature on the IEEE 802 11a Standard 1 Speth Classen Meyr Frame synchronization of OFDM systems in frequency selective fading channels VTC 97 pp 1807 1811 2 Schmidl Cox Robust Frequency and Timing Synchronization of OFDM IEEE Trans on Comm Dec 1997 pp 1613 621 3 Minn Zeng Bhargava On Timing Offset Estimation for OFDM IEEE Communication Letters July 2000 pp 242 244 4 Speth Fechtel Fock Meyr Optimum Receiver Design for Wireless Broad Band Systems Using OFDM Part I IEEE Trans On Comm VOL 47 NO 11 Nov 1999 5 Speth Fechtel Fock Meyr Optimum Receiver Design for Wireless Broad Band Systems Using OFDM Part II IEEE Trans On Comm VOL 49 NO 4 April 2001 6 IEEE 802 11a Part 11 WLAN Medium Access Control MAC and Physical Layer PHY specifica tions 4 2 Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS This description gives a rough overview of the signal processing concept of th
235. l R amp S9FSW is abbreviated as R amp S FSW R amp S FSW K91 Contents 1 Preface e 5 11 About this Manuial erret rre aaan Erraina 5 1 2 Documentation Overvlew EE EEEEEEEEEEEEEEEEEE REENEN EEEEE KEREN 6 1 3 Conventions Used in the Documentation c c eeeeeceeeeeeee eee eee NEEN KEEN 7 2 Welcome to the WLAN Application eene 9 2 4 Starting the WLAN Application cccccceeceeeeeeeeee eee eee sense eee enne nennen nnn nennen nn 9 2 2 Understanding the Display Information eee 10 3 Measurements and Result Displays eene 13 3 1 WLAN I Q Measurement Modulation Accuracy Flatness and Tolerance 13 3 2 Frequency Sweep Measurements sese 39 4 Measurement Basis scere inna neuen eoe xk ux xFSEnERE SEN na aS auRncCR ana ege 45 4 1 Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM ike 45 42 Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS n 52 4 3 Physical vs Effective Channels eese nennen nnn nnns 58 4 4 Recognized vs Analyzed PPDUS esee nennen nnn nnns 59 4 5 Demodulation Parameters Logical Filters
236. lay the Magnitude Capture buffer in window 1 at the top of the screen and the selected result type in window 2 below that Any other active windows are closed Use the LAYout commands to change the display see chapter 9 7 Configuring the Result Display on page 184 e Selecting the WLAN IQ Measurement Modulation Accuracy Flatness and Toler e Selecting a Common RF Measurement for WLAN Signals 139 9 4 1 Selecting the WLAN IQ Measurement Modulation Accuracy Flat ness and Tolerance Any of the following commands can be used to return to the WLAN IQ measurement Each of these results are automatically determined when the WLAN IQ measurement is performed The selected measurement must be started explicitely see chapter 9 8 Starting a Mea surement on page 193 CONFigure BURSt CONSt CCARrier IMMediate eee nennen 137 CONFloure BURGCCONSt CSvMboltlMMedatel enne 137 CONFigure BURSt EVM ECARrier IMMediate cesses 137 CONFigure BURSt EVM ESYMbol MMediate IEEE 802 11b and g DSSS 137 CONFigure BURSEEVM ECHipEIMMedidtel 2 2 utate taco ce un SERA SEENEN 137 CONFigure BURSEEVM ESYMbol IMMediate 5 iecore ee tetendit ia 137 GCONFigure BURStPVT IMMediate erret cnt nt nun nnn nne RR ntn a 138 CONFigure BURSESPEGu m FFT IMMeadiate dante aea aiia 138 CONFigure BURSESPEGtrum
237. ld is enabled for Nsts to use Meas only the specified Nsts or Demod all with specified Nsts Remote command SENSe DEMod FORMat NSTSindex on page 171 STBC Field Defines the PPDUs taking part in the analysis according to the Space Time Block Coding STBC field content Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display STBC column see Signal Field on page 35 User Manual 1173 9357 02 06 99 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Auto same All PPDUs using a STBC field content identical to the first recognized type as first PPDU are analyzed PPDU A1st Auto individu All PPDUS are analyzed ally for each PPDU AI Meas only if Only PPDUs with the specified STBC field content are analyzed STBC field 1 1 Stream M1 IEEE 802 11N Meas only if Only PPDUs with the specified STBC field content are analyzed STBC field 2 2 Stream M2 IEEE 802 11N Demod allas All PPDUs are analyzed assuming the specified STBC field content STBC field 1 D1 IEEE 802 11N Demod allas All PPDUSs are analyzed assuming the specified STBC field content STBC field 2 D2 IEEE 802 11N Meas only if Only PPDUs with the specified STBC field content are analyzed STBC 1 Nsts 2Nss M1 I EEE 802 11AC Demod
238. lected WLAN measurement are displayed in SmartGrid mode To activate SmartGrid mode do one of the following B Select the SmartGrid icon from the toolbar e Select the Display Config button in the configuration Overview see chapter 5 2 Display Configuration on page 68 e Press the MEAS CONFIG hardkey and then select the Display Config softkey To close the SmartGrid mode and restore the previous softkey menu select the 2 Close icon in the righthand corner of the toolbar or press any key on the front panel The WLAN measurements provide the following evaluation methods BitStEB SIT ederet pee ER ave dec a de to gd ie dre adve dive pedet aa dated tsi dad D 22 COMSTS AU ON GE 24 Constellation vs Caller eee ecce anon eege Add 25 EVM WVS CaMel MRNA 26 EVM VS D a T ed ee 27 rco Mc 27 PE SP CUMIN cce cerner an E teme Rear s Chea ant tained niae dh ie cup ufa fed ceu 28 GOO STAY HEU 29 Magnitude Capture cecru einen EEEE REEE ETEEN E 29 PLOP Header IEEE 202 1 1b 9 GSS5 E 30 PUT FOL PP eae e tette e e d EIE 31 Result Summary Detalled 5 EEN ENEE EENEG 32 Result Sumimary Global 51 15 0 rrr bd EE ert aea i d ipeta dd de Santee 33 energie 35 Spectm FIalipSg sss ated eeh SA aiaa nn datu q eeu eR RIA S RAM AR n Rate aui a 38 Bitstream This result display shows the demodulated payload data stream for all analyzed PPDUs of the currently captured UO data as indicated in the Magnitude Capture displ
239. limit check for data carriers The limit value is defined by the standard or the user see CALCulate LIMit BURSt EVM DATA MAXimum on page 179 Return values lt LimitCheck gt PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only EEUU RU M User Manual 1173 9357 02 06 204 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG AM D M m P n Retrieving Results CALCulate LIMit BURSt EVM PILot AVERage RESult CALCulate LIMit BURSt EVM PILot MAXimum RESulIt This command returns the result of the average or maximum EVM limit check for pilot carriers The limit value is defined by the standard or the user see CALCulate LIMit BURSt EVM PILot MAXimum on page 179 Return values LimitCheck PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only CALCulate LIMit BURSt FERRor AVERage RESult CALCulate LIMit BURSt FERRor MAXimum RESult This command returns the result of the average or maximum center frequency error limit check The limit value is defined by the standard or the user see CALCulate LIMit BURSt FERRor MAXimum on page 180 Return values LimitCheck PASS The defined limit for the pa
240. log box depends on the standard you selected previously for the WLAN Modulation Accuracy Flatness measurement see Standard on page 72 o You must select the SEM file with the pre defined settings required by the standard man For further details about the Spectrum Emission Mask measurements refer to Spectrum Emission Mask Measurement in the R amp S FSW User Manual To restore adapted measurement parameters the following parameters are saved on exiting and are restored on re entering this measurement e Reference level and reference level offset e Sweep time e Span The main measurement menus for the frequency sweep measurements are identical to the Spectrum application 5 4 3 Occupied Bandwidth The Occupied Bandwidth measurement is performed as in the Spectrum application with default settings Table 5 4 Predefined settings for WLAN OBW measurements Setting Default value 96 Power Bandwidth 99 Channel bandwidth 3 84 MHz The Occupied Bandwidth measurement determines the bandwidth that the signal occu pies The occupied bandwidth is defined as the bandwidth in which in default settings 99 of the total signal power is to be found The percentage of the signal power to be included in the bandwidth measurement can be changed For further details about the Occupied Bandwidth measurements refer to Measuring the Occupied Bandwidth in the R amp S FSW User Manual User Manual 1173 9357 02 0
241. ly PPDUs with the specified STBC field content are analyzed STBC field 1 1 Stream M1 IEEE 802 11N Meas only if Only PPDUs with the specified STBC field content are analyzed STBC field 2 2 Stream M2 IEEE 802 11N Demod all as All PPDUs are analyzed assuming the specified STBC field content STBC field 1 D1 IEEE 802 11N Demod allas All PPDUs are analyzed assuming the specified STBC field content STBC field 2 D2 IEEE 802 11N eee User Manual 1173 9357 02 06 106 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Meas only if Only PPDUs with the specified STBC field content are analyzed STBC 1 Nsts 2Nss M1 I EEE 802 11AC Demod allas All PPDUs are analyzed assuming the specified STBC field content STBC 1 Nsts 2Nss D1 I EEE 802 11AC Remote command CONFigure WLAN STBC AUTO TYPE on page 166 Extension Spatial Streams sounding Defines the PPDUs taking part in the analysis according to the Ness field content Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display NESS column see Signal Field on page 35 Auto same All PPDUs using a Ness value identical to the first recognized PPDU type as first are analyzed PPDU A1st Auto individu All PPDUs are analyzed ally for each PPDU Al Me
242. ly be used in one way others work in two ways setting and query If not indicated otherwise the commands can be used for settings and queries The syntax of a SCPI command consists of a header and in most cases one or more parameters To use a command as a query you have to append a question mark after the last header element even if the command contains a parameter A header contains one or more keywords separated by a colon Header and parameters are separated by a white space ASCII code 0 to 9 11 to 32 decimal e g blank If there is more than one parameter for a command these are separated by a comma from one another Only the most important characteristics that you need to know when working with SCPI commands are described here For a more complete description refer to the User Manual of the R amp S FSW Remote command examples Note that some remote command examples mentioned in this general introduction may not be supported by this particular application Conventions used in Descriptions Note the following conventions used in the remote command descriptions e Command usage User Manual 1173 9357 02 06 127 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 2 2 9 2 3 Introduction If not specified otherwise commands can be used both for setting and for querying parameters If a command can be used for setting or querying only or if it initiates an event the usage is stated explicitely
243. m Mean PPDU power Crest factor dB The ratio of the peak power to the mean power of the signal also called Peak to Average Power Ratio PAPR the limits can be changed via remote control not manually see chapter 9 5 9 Limits on page 178 in this case the currently defined limits are displayed here Table 3 2 WLAN I Q parameters for IEEE 802 11b or g DSSS Parameter Description Sample Rate Fs Input sample rate PPDU Type of the analyzed PPDU Data Rate Data rate used for analysis of the signal SGL Indicates single measurement mode as opposed to continuous Standard Selected WLAN measurement standard Meas Setup Number of Transmitter Tx and Receiver Rx channels used in the measure ment Capture time Duration of signal capture No of Samples Number of samples captured sample rate capture time No of Data Symbols The minimum and maximum number of data symbols that a PPDU may have if it is to be considered in results analysis Analyzed PPDUs For statistical evaluation of PPDUs see PPDU Statistic Count No of PPDUs to Analyze on page 109 x PPDUs of totally required y PPDUs have been analyzed so far lt z gt indicates the number of analyzed PPDUs in the most recent sweep Number of recognized Number of PPDUs recognized in capture buffer PPDUS global Number of analyzed Number of analyzed PPDUS in capture buffer PPDUS global Number of an
244. m the Signal field of each recognized PPDU This field contains information on the modulation used for transmission This result display is not available for single carrier measurements IEEE 802 11b g DSSS use PLCP Header IEEE 802 11b g GSSS instead 2 Signal Field Format MCS CBW HT SIG Len Sym SNRA STBC GI Ness SE Alst Alst Estimated Alst 1 i i 40 Alst Fig 3 14 Signal Field display for IEEE 802 11n The signal field information is provided as a decoded bit sequence and where appropri ate also in human readable form beneath the bit sequence for each PPDU The currently applied demodulation settings as defined by the user see chapter 5 3 8 Demodulation on page 93 are indicated beneath the table header for reference Since the demodulation settings define which PPDUs are to be analyzed this logical filter may be the reason if the Signal Field display is not as expected Table 3 5 Demodulation parameters and results for Signal Field result display IEEE 802 11a g OFDM Parameter Description Format PPDU format used for measurement Not part of the IEEE 802 11a g OFDM signal field displayed for convenience see PPDU Format to measure on page 94 CBW Channel bandwidth to measure Not part of the signal field displayed for conven ience Rate Mbit s Symbol rate per second R Reserved bit Length Sym Human readable length of payload in OFDM symbols User Manual 117
245. mand Parameters lt WindowName gt String containing the name of the existing window By default the name of a window is the same as its index To determine the name and index of all active windows use the LAYout CATalog WINDow query lt WindowType gt Type of result display you want to use in the existing window See LAYout ADD WINDow on page 186 for a list of available window types Example LAY REPL WIND 1 MTAB Replaces the result display in window 1 with a marker table LAYout SPLitter lt Index1 gt lt Index2 gt lt Position gt This command changes the position of a splitter and thus controls the size of the windows on each side of the splitter As opposed to the DISPlay WINDow lt n gt SIZE on page 185 command the LAYout SPLitter changes the size of all windows to either side of the splitter perma nently it does not just maximize a single window temporarily Note that windows must have a certain minimum size If the position you define conflicts with the minimum size of any of the affected windows the command will not work but does not return an error y 100 x 100 y 100 1 01 GHz 102 12 dim x 0 y 0 x 100 Fig 9 1 SmartGrid coordinates for remote control of the splitters T User Manual 1173 9357 02 06 189 R amp S9FSW K91 Remote Commands for WLAN Measurements Configuring the Result Display Parameters Index1 The index of one window the splitter controls Index2
246. mbol until all the and Q data for the analyzed OFDM Symbols is exhaus ted Note that as opposed to the Constellation results the DC null subcarriers are included as NaNs Nuseq pairs of and Q data per OFDM Symbol OFDM Symbol 1 h11 Q4 4 Uu Du li Nusea Q1 Nusea OFDM Symbol 2 121 Q2 1 122 Q25 l2 used Q2 use OFDM Symbol N Ins Qu In2 Qu2 IN Nused Qu Nused LEE User Manual 1173 9357 02 06 217 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 9 4 5 9 9 4 6 9 9 4 7 Retrieving Results EVM vs Carrier Three trace types are provided for this evaluation Table 9 13 Query parameter and results for EVM vs Carrier TRACE1 The minimum EVM value over the analyzed PPDUs for each of the Nuseg subcarriers TRACE2 The average EVM value over the analyzed PPDUs for each of the Neg subcarriers TRACES The maximum EVM value over the analyzed PPDUs for each of the Nusea subcarriers Each EVM value is returned as a floating point number expressed in units of dB Supported data formats see FORMat DATA on page 210 ASCii UINT Example For EVM the EVM of the m th analyzed PPDU for the subcarrier n 1 2 Nusea TRACE1 Minimum EVM value per subcarrier Minimum EVM 14 EVM24 EVMstatistic Length 1 gt Minimum EVM value for subcarrier Nyseq 1 2 Minimum EVM 2 EVM 5 EVMsatistic Length 2 H Minimum EVM value for s
247. mmand returns eight values in the following order lt No gt lt StartFreq gt lt StopFreq gt lt RBW gt lt PeakFreq gt lt PowerAbs gt lt PowerRel gt lt PowerDelta gt lt Limit Check gt lt Unused1 gt lt Unused2 gt lt No gt range number lt StartFreq gt lt StopFreq gt start and stop frequency of the range RBW resolution bandwidth lt PeakFreq gt frequency of the peak in a range lt PowerAbs gt absolute power of the peak in dBm PowerRel power of the peak in relation to the channel power in dBc lt PowerDelta gt distance from the peak to the limit line in dB positive values indicate a failed limit check lt LimitCheck gt state of the limit check 0 PASS 1 FAIL lt Unused1 gt lt Unused2 gt reserved 0 0 User Manual 1173 9357 02 06 211 R amp SS9FSW K91 Remote Commands for WLAN Measurements mAA H ew Retrieving Results TRACe lt n gt DATA X lt TraceNumber gt This command queries the horizontal trace data for each sweep point in the specified window for example the frequency in frequency domain or the time in time domain measurements This is especially useful for traces with non equidistant x values e g for SEM or Spurious Emissions measurements Query parameters lt TraceNumber gt Trace number TRACE1 TRACE6 Example TRAC3 X TRACE1
248. mn O W 2 9 enr Status Registers 9 11 2 1 General Status Register Commands STATUS BISESBL cass naci tatto crac inue cra dpa ntu ve eR anda cent ci tack o nae uda edt a dian cuan a Rd DE raus 226 mo KN e he NEXT Cn 226 STATus PRESet This command resets the edge detectors and ENAB1e parts of all registers to a defined value All PTRansition parts are set to FFFFh i e all transitions from 0 to 1 are detec ted All NTRansition parts are set to O i e a transition from 1 to 0 in a CONDition bit is not detected The ENAB1e part of the STATus OPERation and STATus QUEStionable registers are set to 0 i e all events in these registers are not passed on Usage Event STATus QUEue NEXT This command queries the most recent error queue entry and deletes it Positive error numbers indicate device specific errors negative error numbers are error messages defined by SCPI If the error queue is empty the error number 0 No error is returned Usage Query only 9 11 2 2 Reading Out the EVENt Part STATus OPERation EVENt STATus QUEStionable EVENt STATus QUEStionable ACPLimit EVENt lt ChannelName gt STATus QUEStionable LIMit lt n gt EVENt lt ChannelName gt STATus QUEStionable SYNC EVENt lt ChannelName gt This command reads out the EVENt section of the status register The command also deletes the contents of the EV
249. mn see Signal Field on page 35 Auto same All PPDUs using the MCS index identical to the first recognized PPDU type as first are analyzed PPDU A1st Auto individ All PPDUs are analyzed ually for each PPDU Al Meas only the Only PPDUs with the MCS index specified for the MCS Index setting specified are analyzed MCS M I User Manual 1173 9357 02 06 105 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Demod all with The MCS Index setting is used for all PPDUs specified MCS D Remote command SENSe DEMod FORMat MCSindex MODE on page 170 MCS Index Defines the MCS index of the PPDUs taking part in the analysis manually This field is enabled for MCS index to use Meas only the specified MCS or Demod all with specified MCS Remote command SENSe DEMod FORMat MCSindex on page 170 STBC Field Defines the PPDUs taking part in the analysis according to the Space Time Block Coding STBC field content Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display STBC column see Signal Field on page 35 Auto same All PPDUs using a STBC field content identical to the first recognized type as first PPDU are analyzed PPDU A1st Auto individu All PPDUS are analyzed ally for each PPDU Al Meas only if On
250. mpedance 50 O or 75 Q see Impedance on page 74 conversion to other units is possible The following units are available and directly convertible dBm dBmV dByV dBpA dBpW Volt Ampere I User Manual 1173 9357 02 06 80 R amp S FSW K91 Configuration ma a 8 8s WLAN IQ Measurement Modulation Accuracy Flatness Tolerance e Watt Remote command INPut IMPedance on page 143 CALCulate lt n gt UNIT POWer on page 147 Setting the Reference Level Automatically Auto Level Reference Level Settings Automatically determines the optimal reference level for the current input data At the same time the internal attenuators and the preamplifier are adjusted so the signal to noise ratio is optimized while signal compression clipping and overload conditions are minimized In order to do so a level measurement is performed to determine the optimal reference level You can change the measurement time for the level measurement if necessary see Changing the Automatic Measurement Time Meastime Manual on page 112 Remote command CONFigure POWer AUTO on page 147 RF Attenuation Defines the attenuation applied to the RF input Attenuation Mode Value RF Attenuation The RF attenuation can be set automatically as a function of the selected reference level Auto mode This ensures that the optimum RF attenuation is always used It is the default sett
251. n MSRA mode this function is only available for the MSRA Master Remote command SENSe FREQuency OFFSet on page 146 Amplitude Settings Amplitude settings determine how the R amp S FSW must process or display the expected input power levels To configure the amplitude settings Amplitude settings can be configured via the AMPT key or in the Amplitude dialog box gt To display the Amplitude dialog box do one of the following e Select Input Frontend from the Overview and then switch to the Amplitude tab e Select the AMPT key and then the Amplitude Config softkey REESE E TR e e LL A A LL LLLLLULUUALX User Manual 1173 9357 02 06 78 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance WLAN 3 mm mms Amplitude Scale Reference Level Input Settings Mode Wanual Preamplifier Reference Lvl Tir eeu eet DA 10 0 dBm Input Coupling Offset 0 0 dB Unit Impedance Auto Level RF Attenuation Electronic Attenuation State Mode Manual Auto Mode Value Reference Level Seluhgj 2 tort tein b etate ede a aded RR Ede reda ada 79 L Reference Level Mode 79 L Reference Level 80 L Signal Level MSL 80 L Shifting the Display Offset 80 m c PT E 80 L Setting the Reference Level Automatically Auto Level 81 FRPP uiro e A E 81 L Attenuation Mode Value testata anta tha tata ninan 81 Using El
252. n page 85 Note on external triggers If a measurement is configured to wait for an external trigger signal in a remote control program remote control is blocked until the trigger is received and the program can con tinue Make sure this situation is avoided in your remote control programs Parameters Source Example Manual operation IMMediate Free Run EXTernal Trigger signal from the TRIGGER INPUT connector EXT2 Trigger signal from the TRIGGER INPUT OUTPUT connector Note Connector must be configured for Input EXT3 Trigger signal from the TRIGGER 3 INPUT OUTPUT connector Note Connector must be configured for Input RFPower First intermediate frequency IFPower Second intermediate frequency IQPower Magnitude of sampled UO data For applications that process UO data such as the UO Analyzer or optional applications TIME Time interval For frequency and time domain measurements only PSEN External power sensor RST IMMediate TRIG SOUR EXT Selects the external trigger input as source of the trigger signal See Trigger Source Settings on page 85 See Trigger Source on page 86 See Free Run on page 86 See External Trigger 1 2 3 on page 86 See IF Power on page 86 See I Q Power on page 87 See RF Power on page 87 See Time on page 87 See Power Sensor on page 87 TRIGger SEQuence TIME RINTerval Interval This command defines the repetition interval for th
253. n quadrature offset average quadrature offset max quadrature offset min EVM all bursts average EVM all bursts max EVM all bursts min EVM data carriers average EVM data carriers gt max EVM data carriers min EVM pilots average EVM pilots gt max EVM pilots FETCh BURSt CRESt AVERage FETCh BURSt CRESt MAXimum FETCh BURSt CRESt MINimum This command returns the average maximum or minimum determined CREST factor ratio of peak power to average power in dB For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt EVM ALL AVERage FETCh BURSt EVM ALL MAXimum FETCh BURSt EVM ALL MINimum This command returns the average maximum or minimum EVM in dB This is a combined figure that represents the pilot data and the free carrier T User Manual 1173 9357 02 06 200 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG OC P gg J Retrieving Results For details see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parame ters on page 13 Usage Query only FETCh BURSt EVM DATA AVERage FETCh BURSt EVM DATA MAXimum FETCh BURSt EVM DATA MINimum This command returns the average maximum or minimum EVM for the data carrier in dB For details see chapter 3 1 1
254. ng settings which represent the frontend of the measurement setup EE 21 0 Mm 144 e Amplitude ee 1 dreetece eie pel ba tee baee a Reader e Ene dern cond 146 9 5 3 4 Frequency SENS amp FREQUEN DENT E 145 SENS amp IFREDuUsncy CENTE STEP innii oro genre teuer ene ERA UE e ERR RRRLHR Elo cU Mr paE 145 IGENSelFREOuenc CENTer STEPAUTO teet tenete ttt 145 E EI ene err erret re hetero in Reese XR RR EE en dere end 146 EEUU RA a User Manual 1173 9357 02 06 144 R amp SS9FSW K91 Remote Commands for WLAN Measurements PENEAMECAECMCMO CI A H ua n PH Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe FREQuency CENTer Frequency This command defines the center frequency Parameters Frequency The allowed range and fmax is specified in the data sheet UP Increases the center frequency by the step defined using the SENSe FREQuency CENTer STEP command DOWN Decreases the center frequency by the step defined using the SENSe FREQuency CENTer STEP command RST fmax 2 Default unit Hz Example FREQ CENT 100 MHz FREQ CENT STEP 10 MHz FREQ CENT UP Sets the center frequency to 110 MHz Usage SCPI confirmed Manual operation See Frequency on page 72 See Center on page 77 SENSe FREQuency CENTer STEP lt StepSize gt This command defin
255. ng the transmission of these data bytes all end or other control signs are ignored until all bytes are transmitted ERREUR EA M User Manual 1173 9357 02 06 131 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 3 Activating WLAN Measurements 0 specifies a data block of indefinite length The use of the indefinite format requires a NL END message to terminate the data block This format is useful when the length of the transmission is not known or if speed or other considerations prevent segmentation of the data into blocks of definite length Activating WLAN Measurements WLAN measurements require a special application on the R amp S FSW R amp S FSW K91 The measurement is started immediately with the default settings o These are basic R amp S FSW commands listed here for your convenience INS Eromemnb CREAS DUPLICI cette ditor A eek bien tuere deena 132 INS Tiumen CRENERNEW EE 132 INSTramentGREate REPLCe 13 111 iactat iniaa aas sce sa kasdacuissancuiddalsca kiki SNE 133 INS TramentDELele eessen EE RAN Aen 133 INS TrUmMER UST A 133 INS WR INNS cucine dE aa i eene aa n e ead aae o Edu deet deen 135 En Hoer DEE 135 SYSTem PRESetCHANnel EXECuUte i aeo oorr en nocere aE E EENET aa 135 INSTrument CREate DUPLicate This command duplicates the currently selected measurement channel i e starts a new measurement channel of the same type and with the identic
256. nnelName1 gt lt ChannelType gt lt ChannelName2 gt This command replaces a measurement channel with another one Parameters lt ChannelName1 gt String containing the name of the measurement channel you want to replace lt ChannelType gt Channel type of the new channel For a list of available channel types see table 9 3 lt ChannelName2 gt String containing the name of the new channel Note If the specified name for a new channel already exists the default name extended by a sequential number is used for the new channel see table 9 3 Example INST CRE REPL Spectrum2 IQ IQAnalyzer Replaces the channel named Spectrum2 by a new measurement channel of type IQ Analyzer named IQAnalyzer INSTrument DELete lt ChannelName gt This command deletes a measurement channel If you delete the last measurement channel the default Spectrum channel is activated Parameters lt ChannelName gt String containing the name of the channel you want to delete A measurement channel must exist in order to be able delete it Example INST DEL Spectrum4 Deletes the spectrum channel with the name Spectrum4 INSTrument LIST This command queries all active measurement channels This is useful in order to obtain the names of the existing measurement channels which are required in order to replace or delete the channels Return values lt ChannelType gt For each channel the command returns the
257. not available Possible reasons channel matrix not square or singular to working precision The Physical Channel results could not be calculated for one or both of the following reasons e The spatial mapping can not be applied due to a rectangular mapping matrix the number of space time streams is not equal to the number of transmit antennas e The spatial mapping matrices are singular to working precision PPDUS are dismissed due to inconsistencies Hint PPDU requires at least one payload symbol Currently at least one payload symbol is required in order to successfully analyze the PPDU Null data packet NDP sounding PPDUS will generate this message Hint PPDU dismissed due to a mismatch with the PPDU format to be analyzed The properties causing the mismatches for this PPDU are highlighted Hint PPDU dismissed due to truncation The first or the last PPDU was truncated during the signal capture process for example Hint PPDU dismissed due to HT SIG inconsistencies One or more of the following HT SIG decoding results are outside of specified range MCS index Number of additional STBC streams Number of space time streams derived from MCS and STBC CRC Check failed Non zero tail bits Hint PPDU dismissed because payload channel estimation was not possible The payload based channel estimation was not possible because the channel matrix is singular to working precision Hint Channel matrix singular to working pr
258. nt Thus you can easily configure an entire measurement channel from input over processing to output and analysis by stepping through the dialog boxes as indicated in the Overview The available settings and functions in the Overview vary depending on the currently selected measurement For frequency sweep measurements see chapter 5 4 Fre quency Sweep Measurements on page 114 For the WLAN IQ measurement the Overview provides quick access to the following configuration dialog boxes listed in the recommended order of processing 1 Select Measurement uc IEEE UAE as User Manual 1173 9357 02 06 70 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance See Selecting the measurement type on page 66 2 Signal Description See chapter 5 3 3 Signal Description on page 72 3 Input Frontend See and chapter 5 3 4 Input and Frontend Settings on page 72 4 Signal Capture See chapter 5 3 5 Signal Capture Data Acquisition on page 82 5 Synchronization OFDM demodulation See chapter 5 3 6 Synchronization and OFDM Demodulation on page 90 6 Tracking Channel Estimation See chapter 5 3 7 Tracking and Channel Estimation on page 91 7 Demodulation See chapter 5 3 8 Demodulation on page 93 8 Evaluation Range See chapter 5 3 9 Evaluation Range on page 108 9 Display Configuration See chapter 5 2 Display Conf
259. nt Channel Power measurement analyzes the power of the TX channel and the power of adjacent and alternate channels on the left and right side of the TX channel The number of TX channels and adjacent channels can be modified as well as the band class The bandwidth and power of the TX channel and the bandwidth spacing and power of the adjacent and alternate channels are displayed in the Result Summary Channel Power ACLR measurements are performed as in the Spectrum application with the following predefined settings according to WLAN specifications adjacent channel leakage ratio User Manual 1173 9357 02 06 115 R amp S FSW K91 Configuration a O n awe Frequency Sweep Measurements Table 5 2 Predefined settings for WLAN ACLR Channel Power measurements Setting Default value ACLR Standard same as defined in WLAN signal descrip tion see Standard on page 72 Number of adjacent channels 3 Reference channel Max power Tx channel Channel bandwidth 20 MHz For further details about the ACLR measurements refer to Measuring Channel Power and Adjacent Channel Power in the R amp S FSW User Manual To restore adapted measurement parameters the following parameters are saved on exiting and are restored on re entering this measurement e Reference level and reference level offset e RBW VBW e Sweep time e Span e Number of adjacent channels e
260. nt Channels and Sequencer Function 5 Configuration The default WLAN UO measurement captures the UO data from the WLAN signal and determines various characteristic signal parameters such as the modulation accuracy spectrum flatness center frequency tolerance and symbol clock tolerance in just one measurement see chapter 3 1 WLAN UO Measurement Modulation Accuracy Flat ness and Tolerance on page 13 Other parameters specified in the WLAN 802 11 standard must be determined in sepa rate measurements see chapter 5 4 Frequency Sweep Measurements on page 114 In settings required to configure each of these measurements are described here Selecting the measurement type gt To select a different measurement type do one of the following e Tap the Overview softkey In the Overview tap the Select Measurement button Select the required measurement e Press the MEAS key on the front panel In the Select Measurement dialog box select the required measurement e Multiple Measurement Channels and Sequencer Function sss 66 Display Configuration s ecuucc ce eec cer nennen e rena euch secre Renner ce Ee Rae e 68 e WLAN IQ Measurement Modulation Accuracy Flatness Tolerance 68 e Frequency Sweep Measurement ccccceccecccscceeceeecceeceeeceeeceeeeeeeeeeeeeeeeeeeess 114 5 1 Multiple Measurement Channels and Sequencer Func tion When you activate an ap
261. ntioned above 0 98 20 1og10 1 12 1 EE RU N User Manual 1173 9357 02 06 17 3 1 1 3 WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Fig 3 2 Positive gain imbalance Negative values mean that the vector is amplified more than the Q vector by the corre sponding percentage For example using the figures mentioned above 0 98 20 log10 1 1 12 Fig 3 3 Negative gain imbalance Quadrature Offset An ideal UO modulator sets the phase angle between the and Q path mixer to exactly 90 degrees With a quadrature offset the phase angle deviates from the ideal 90 degrees the amplitudes of both components are of the same size In the vector diagram the quadrature offset causes the coordinate system to shift A positive quadrature offset means a phase angle greater than 90 degrees R amp S FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy Flatness and Tolerance da da dr dz p mi cb W gm u Fig 3 4 Positive quadrature offset A negative quadrature offset means a phase angle less than 90 degrees da 4a dr dz 4p mi cb W gm u Fig 3 5 Negative quadrature offset 3 1 1 4 RF Carrier Suppression IEEE 802 11b g DSSS Standard definition The RF carrier suppression measured at the channel center frequency shall be at least 15 dB below the peak SIN x x power spectrum The RF carrier suppression shall be measured while transmitting a repetit
262. nts sss eene 152 9 5 4 1 General Capture Settings SENSe BANDwidth RESolution FIL Ter S TATe 1 2 eaaa 151 SENSe SWAPiq ecce tette tenet teet te tette senses De 0a 151 SENSGASW Be ee DLE 152 WPRAC SOS RAR NC m 152 SENSe BANDwidth RESolution FlLTer STATe State This remote control command enables or disables use of the adjacent channel filter If activated only the useful signal is analyzed all signal data in adjacent channels is removed by the filter This setting improves the signal to noise ratio and thus the EVM results for signals with strong or a large number of adjacent channels However for some measurements information on the effects of adjacent channels on the measured signal may be of interest Parameters lt State gt ON OFF 0 1 RST 1 Manual operation See Suppressing Filter out Adjacent Channels IEEE 802 11A G OFDM AC N on page 84 SENSe SWAPiq State This command defines whether or not the recorded IQ pairs should be swapped I lt gt Q before being processed Swapping and Q inverts the sideband This is useful if the DUT interchanged the and Q parts of the signal then the R amp S FSW can do the same to compensate for it Parameters lt State gt ON and Q signals are interchanged Inverted sideband Q j I OFF and Q signals are not interchanged Normal sideband I j Q
263. numeric results for RF data the suffixes lt n gt for CALCulate and lt k gt for LIMit are irrelevant CAL CulateLlMit ACbowerACHannel REGu innii nadrain nna 206 CAL CulateLlMit ACbower Al Temate chsRESuI 206 CAL Culate EE 207 GAL CulateMARKerFU NCtGmPOWenRESUll aate NEESS aa i 207 CALC ulates inet MARKeremisiX nie Dee Er eee PIE ea 209 GALGulate STATistics RESull E EE 209 CALCulate LIMit ACPower ACHannel RESult CALCulate LIMit ACPower ALTernate lt ch gt RESult This command queries the state of the limit check for the adjacent or alternate channels in an ACLR measurement To get a valid result you have to perform a complete measurement with synchronization to the end of the measurement before reading out the result This is only possible for single sweeps See also 1NTTiate CONTinuous on page 194 Return values lt LowerChan gt text value lt UpperChan gt The command returns two results The first is the result for the lower the second for the upper adjacent or alternate channel PASSED Limit check has passed FAIL Limit check has failed Example INIT IMM WAI CALC LIM ACP ACH RES PASSED PASSED Usage Query only eee User Manual 1173 9357 02 06 206 R amp SS9FSW K91 Remote Commands for WLAN Measurements Retrieving Results CALCulate LIMit lt k gt FAIL This command queries the result of a limit check For measurements in the R amp S FSW WLAN application
264. o Auto same type as first PPDU ALL All recognized PPDUs are analyzed according to their individual STBC corresponds to Auto individually for each PPDU MO M1 M2 Measure only if STBC field 0 1 2 For details see STBC Field on page 99 DO D1 D2 Demod all as STBC field 0 1 2 For details see STBC Field on page 99 CONF WLAN STBC AUTO TYPE MO See STBC Field on page 99 SENSe BANDwidth CHANnel AUTO TYPE Bandwidth This remote control command specifies the bandwidth in which the PPDUs are analyzed This command is only available for standards IEEE 802 11a ac n Note that channel bandwidths larger than 10 MHz require a R amp S FSW bandwidth exten sion option see chapter A 1 Sample Rate and Maximum Usable UO Bandwidth for RF Input on page 230 User Manual 1173 9357 02 06 166 R amp SS9FSW K91 Remote Commands for WLAN Measurements PREGA a d J JP ag Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters Bandwidth FBURst ALL MB5 MB10 MB20 MB40 MB80 DB20 DB40 DB80 FBURSt The channel bandwidth of the first valid PPDU is detected and subsequent PPDUs are analyzed only if they have the same chan nel bandwidth corresponds to Auto same type as first PPDU ALL All PPDUs are analyzed regardless of the channel bandwidth cor
265. o be considered in results analysis Analyzed PPDUs For statistical evaluation of PPDUs see PPDU Statistic Count No of PPDUs to Analyze on page 109 x PPDUS of totally required y PPDUs have been analyzed so far lt z gt indicates the number of analyzed PPDUs in the most recent Sweep Number of recognized PPDUS global Number of analyzed PPDUS global Number of PPDUs recognized in capture buffer Number of analyzed PPDUS in capture buffer Number of analyzed PPDUs in physical chan nel Number of PPDUs analyzed in entire signal if available Pilot bit error rate 96 EVM all carriers dB EVM data carriers dB EVM Error Vector Magnitude of the payload symbols over all carriers the cor responding limits specified in the standard are also indicated EVM Error Vector Magnitude of the payload symbols over all data carriers the corresponding limits specified in the standard are also indicated EVM pilot carriers dB EVM Error Vector Magnitude of the payload symbols over all pilot carriers the corresponding limits specified in the standard are also indicated Center frequency error Hz Frequency error between the signal and the current center frequency of the R amp S FSW the corresponding limits specified in the standard are also indicated The absolute frequency error includes the frequency error of the R amp S FSW and that of the DUT If possible t
266. oaded You do this using the frontend parameters Consider the fol lowing recommendations Reference level Adapt the R amp S FSW s hardware to the expected maximum signal level by setting the Reference Level to this maximum Compensate for any external attenuation or gain into consideration by defining a Reference Level offset Attenuation To optimize the signal to noise ratio of the measurement for high signal levels and to protect the R amp S FSW from hardware damage provide for a high attenuation Use AC coupling for DC input voltage IECH User Manual 1173 9357 02 06 62 R amp SS9FSW K91 Measurement Basics mu ON X H n Triggered measurements Amplification To optimize the signal to noise ratio of the measurement for low signal levels the signal level in the R amp S FSW should be as high as possible but without introducing compression clipping or overload Provide for early amplification by the preamplifier and a low attenu ation Impedance When measuring in a 75 O system connect an external matching pad to the RF input and adapt the reference impedance for power results The insertion loss is compensated for numerically 4 8 Triggered measurements In a basic sweep measurement with default settings the sweep is started immediately when you start the measurement for example by pressing the RUN SINGLE key How ever sometime
267. on a QJ A Uem UN NM N G NUP RUNS WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Auto individu All PSDUs are analyzed ally for each PPDU Al Meas only the Only PSDUs with the modulation specified by the PSDU Modulation specified setting are analyzed PSDU Modula tion M Demod all with The PSDU modulation of the PSDU Modulation setting is used for all specified PSDUs PSDU modula tion D Remote command SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 SENSe DEMod FORMat BANalyze on page 168 PSDU Modulation If analysis is restricted to PSDU with a particular modulation type this setting defines which type For details on supported modulation depending on the standard see table 4 1 Remote command SENSe DEMod FORMat BANalyze on page 168 5 3 8 2 Demodulation IEEE 802 11ac The following settings are available for demodulation of IEEE 802 11ac signals mie ER J A JG SE re Demodulation PPDUs to Analyze PPDU Analysis Mode Auto same type as first PPDU H for each property to analyze PPDU Format to measure Auto same type as first PPDU Channel Bandwidth to measure Auto same type as first PPDU EI up to CBW160 MHz MCS Index to use Auto same type as first PPDU MCS Index Nsts to use Auto same type as first PPDU Nsts
268. on a W e Mn WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Frequency amplitude and y axis scaling settings represent the frontend of the mea surement setup For more information on the use and effects of these settings see chapter 4 7 Preparing the R amp S FSW for the Expected Input Signal Frontend Parameters on page 62 e Input Source Settings eene eerta cce die E ba Dd FEE soe Rs 73 e UD OS ner ore praebe nec Doa mcer a decode teda da serene carey Pecererrrrere 75 LUE Frequency E dr EE 77 o Amplitude Se ings isis credere ae die ee AR ET ded PE EEE 78 5 3 4 4 Input Source Settings The input source determines which data the R amp S FSW will analyze Input settings can be configured via the INPUT OUTPUT key in the Input dialog box Some settings are also available in the Amplitude tab of the Amplitude dialog box D The Digital UO input source is currently not available in the R amp S FSW WLAN application e Radio Fregueney ln TT LTE 73 Radio Frequency Input The default input source for the R amp S FSW is Radio Frequency i e the signal at the RF INPUT connector on the front panel of the R amp S FSW If no additional options are installed this is the only available input source ENSE Inno nd McA Input Source Power Sensor Probes Frequency External Input Coupling Mixer Impedance Digital I 9 Q High Pass
269. on and OFDM Demodulaton AAA 90 e Tracking and Channel EStimaligri ertet ia as 91 LEER uci 93 Evalual n E Le E 108 e Result EE e EE EE 111 E TEE ee AMETE ULL 111 Re 113 Import EXport FUNCOMS eee e racer itte teret idee RE re ene 114 5 3 1 Default Settings for WLAN Measurements When you activate the WLAN application the first time a set of parameters is passed on from the currently active application e center frequency and frequency offset e reference level and reference level offset e attenuation e input coupling e YIG filter state After initial setup the parameters for the measurement channel are stored upon exiting and restored upon re entering the channel Thus you can switch between applications quickly and easily Apart from the settings above the following default settings are activated directly after the WLAN application is activated or after selecting Preset Channel Table 5 1 Default settings for WLAN channels Parameter Value Common WLAN settings Digital standard IEEE 802 11a Measurement WLAN 1 Q measurement Input source RF input Attenuation 10 0 dB Capture time 1 0 ms Input sample rate 40 0 MHz Trigger mode Free run Channel estimation Preamble Tracking Phase User Manual 1173 9357 02 06 69 R amp S FSW K91 Configuration mam H AX aaa mm aaa aaa WLAN IQ M
270. on page 113 INITiate IMMediate This command starts a single new measurement You can synchronize to the end of the measurement with OPC OPC or WAI ERREUR RE I T i e LLLLLLMTLALLLALZLLIM i User Manual 1173 9357 02 06 194 R amp SS9FSW K91 Remote Commands for WLAN Measurements EMG MMC HM mJ mgt Starting a Measurement For details on synchronization see the Remote Basics chapter in the R amp S FSW User Manual Example For Spectrum application INIT CONT OFF Switches to single sweep mode DISP WIND TRAC MODE AVER Switches on trace averaging SWE COUN 20 Sets the sweep counter to 20 sweeps INIT WAI Starts the measurement and waits for the end of the 20 sweeps Manual operation See Single Sweep RUN SINGLE on page 113 INITiate SEQuencer ABORt This command stops the currently active sequence of measurements The Sequencer itself is not deactivated so you can start a new sequence immediately using INITiate SEQuencer IMMediate on page 195 To deactivate the Sequencer use SYSTem SEQuencer on page 196 Usage Event Manual operation See Sequencer State on page 67 INITiate SEQuencer IMMediate This command starts a new sequence of measurements by the Sequencer Its effect is similar to the INITiate IMMediate command used for a single measurement Before this
271. one or more of the following results EEUU RU E TR e e LL 1LLLL LLLLULLS User Manual 1173 9357 02 06 16 R amp S FSW K91 Measurements and Result Displays 3 1 1 1 3 1 1 2 WLAN UO Measurement Modulation Accuracy Flatness and Tolerance Table 3 3 Calculated summary results Result type Description Min Minimum measured value Mean Limit Mean measured value limit defined in standard Max Limit Maximum measured value limit defined in standard UO Offset An UO offset indicates a carrier offset with fixed amplitude This results in a constant shift of the I Q axes The offset is normalized by the mean symbol power and displayed in dB Jeiee it Fig 3 1 I Q offset in a vector diagram Gain Imbalance An ideal UO modulator amplifies the and Q signal path by exactly the same degree The imbalance corresponds to the difference in amplification of the and Q channel and therefore to the difference in amplitude of the signal components In the vector diagram the length of the vector changes relative to the length of the Q vector The result is displayed in dB and 96 where 1 dB offset corresponds to roughly 12 96 difference between the and Q gain according to the following equation Imbalance dB 20log Gaing Gain Positive values mean that the Q vector is amplified more than the vector by the corre sponding percentage For example using the figures me
272. optional Digital Baseband Interface R amp S FSW B17 or Analog Baseband Interface R amp S FSW B71 is used for input It is also not avail able for analysis bandwidths 2 320 MHz Triggers the measurement when the magnitude of the sampled UO data exceeds the trigger threshold The trigger bandwidth corresponds to the Usable UO Bandwidth which depends on the sample rate of the captured UO data see Input Sample Rate on page 83 and chapter A 1 Sample Rate and Maximum Usable UO Bandwidth for RF Input on page 230 Remote command TRIG SOUR IQP see TRIGger SEQuence SOURce on page 156 RF Power Trigger Source Trigger Source Settings Defines triggering of the measurement via signals which are outside the displayed mea surement range For this purpose the instrument uses a level detector at the first intermediate frequency The input signal must be in the frequency range between 500 MHz and 8 GHz The resulting trigger level at the RF input depends on the RF attenuation and preamplification For details on available trigger levels see the data sheet Note If the input signal contains frequencies outside of this range e g for fullspan measurements the sweep may be aborted and a message indicating the allowed input frequencies is displayed in the status bar A Trigger Offset Trigger Polarity and Trigger Holdoff to improve the trigger stability can be defined for the RF trigger but no Hysteresis Remote
273. or Single Carrier Measurements A block diagram of the measurement application is shown below in figure 4 2 The base band signal of an IEEE 802 11b or g DSSS wireless LAN system transmitter is sampled with a sample rate of 44 MHz The first task of the measurement application is to detect the position of the PPDU within the measurement signal r4 v The detection algorithm is able to find the the beginning of short and long PPDUs and can distinguish between them The algorithm also detects the initial state of the scrambler which is not specified by the IEEE 802 11 standard If the start position of the PPDU is known the header of the PPDU can be demodulated The bits transmitted in the header provide information about the length of the PPDU and the modulation type used in the PSDU Once the start position and the PPDU length are fully known better estimates of timing offset timing drift frequency offset and phase offset can be calculated using the entire data of the PPDU At this point of the signal processing demodulation can be performed without decision error After demodulation the normalized in terms of power and undisturbed reference signal s v is available If the frequency offset is not constant and varies with time the frequency offset and phase offset in several partitions of the PPDU must be estimated and corrected Additionally timing offset timing drift and gain factor can be estimated and corrected in several par
274. or a multiple zoom To define a zoom area you first have to turn the zoom on 1 Frequency Sweep iRm e 1 origin of coordinate system x1 0 y1 0 2 end point of system x2 100 y2 100 3 zoom area e g x1 60 y1 30 x2 80 y2 75 Suffix zoom 1 4 Selects the zoom window Ee User Manual 1173 9357 02 06 223 R amp S9FSW K91 Remote Commands for WLAN Measurements Status Registers Parameters lt x1 gt lt y1 gt Diagram coordinates in of the complete diagram that define the lt x2 gt lt y2 gt zoom area The lower left corner is the origin of coordinate system The upper right corner is the end point of the system Range 0 to 100 Default unit PCT DISPlay WINDow lt n gt ZOOM MULTiple lt zoom gt STATe State This command turns the mutliple zoom on and off Suffix lt zoom gt 1 4 Selects the zoom window If you turn off one of the zoom windows all subsequent zoom win dows move up one position Parameters lt State gt ON OFF RST OFF Status Registers The WLAN application uses the standard status registers of the R amp S FSW depending on the measurement type However some registers are used differently Only those differences are described in the following sections For details on the common R amp S FSW status registers refer to the description of remote control basics in the R amp S FSW User Manual o RST does not influence the status regis
275. or other devices For details on connectors refer to the R amp S FSW Getting Started manual Front Rear Panel View chapters o How to provide trigger signals as output is described in detail in the R amp S FSW User Manual Output settings can be configured via the INPUT OUTPUT key or in the Outputs dialog box Output Digital IQ IF Video Output IF Out Frequency Noise Source Trigger 2 Trigger 3 E E E RR 75 TIT A EE 76 L Output ageet 76 o mcd PR TT 76 G 17 ENERO 76 GE 77 Noise Source Switches the supply voltage for an external noise source on or off External noise sources are useful when you are measuring power levels that fall below the noise floor of the R amp S FSW itself for example when measuring the noise level of a DUT User Manual 1173 9357 02 06 75 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance For details see chapter 4 6 2 Input from Noise Sources on page 61 Remote command DIAGnostic SERVice NSOurce on page 144 Trigger 2 3 Defines the usage of the variable TRIGGER INPUT OUTPUT connectors where Trigger 2 TRIGGER INPUT OUTPUT connector on the front panel Trigger 3 TRIGGER 3 INPUT OUTPUT connector on the rear panel Trigger 1 is INPUT only Note Providing trigger signals as output is described in detail in the R amp S FSW User Manual Input The signal at the connector is used as an external trig
276. ore does not have any data associated with it with no return data being provided Supported data formats ASCii UINT see FORMat DATA on page 210 CCDF Complementary Cumulative Distribution Function The length of the results varies up to a maximum of 201 data points is returned following a data count value The first value in the return data represents the quantity of probability values that follow Each of the potential 201 data points is returned as a probability value and represents the total number of samples that are equal to or exceed the current mean power level Probability data is returned up to the power level that contains at least one sample It is highly unlikely that the full 201 data values will ever be returned Each probability value is returned as a floating point number with a value between 0 and 1 The syntax of the result is thus N CCDF 0 CCDF 1 10 CCDF 2 10 CCDF N 1 10 Constellation This measurement represents the complex constellation points as and Q data See for example IEEE Std 802 11 2012 Fig 18 10 BPSK QPSK 16 QAM and 64 QAM con stellation bit encoding Each and Q point is returned in floating point format Data is returned as a repeating array of interleaved and Q data in groups of selected carriers per OFDM Symbol until all the and Q data for the analyzed OFDM Symbols is exhausted The following carrier selections are possible ERREUR RA N User Manual 1173 9
277. orting FUNCIONS P 114 emori ET 72 114 234 238 UO data remote 220 c mE E EEKAN 114 Extension Spatial Streams PPDUS me T 107 163 External trigger Level remote 2 erri itn teet eire 154 Ee 86 F FFT AWGN channel IEEE 802 11a g OFDM cup nm Signal processing IEEE 802 11a g OFDM Spectrum result display seesssssse Spectrum trace data sss Start offset Start offset remote eene File format lenccqme 234 Files UO data binary XML eee 238 VQ parameter XML eeseeeenen 235 Filters Adjacent channels High pass remote z High pass RF input eesenee 74 YIG remote narrian iinu 143 Format Bata remote rre Edge E EE 210 PPDU remote E 169 User Manual 1173 9357 02 06 248 R amp S9FSW K91 Index Free Run Trigger softkey cs rsrnsiii irasra 86 Frequency Configuration remote usssesssesss 144 Configuration softkey sss 77 Deviation E Error limit remote eese 180 Frequency offset i iore te Er terreni rere 78 Default s Error limit check result remote 205 D gpaqem e e n 46 Frequency sweep measurements COnfIJUTN E 114 Selecting ie ir ia ere nies 115
278. ot AVERage Limit CALCulate LIMit BURSt EVM PILot MAXimum Limit This command sets or queries the maximum error vector magnitude limit for the pilot carriers determined by the default WLAN measurement For details on the EVM results and the default WLAN measurement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 ERREUR RA N User Manual 1173 9357 02 06 179 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 5 10 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters Limit numeric value in dB Theunitfor the EVM parameters can be changed in advance using UNIT EVM on page 203 Default unit DB CALCulate LIMit BURSt FERRor AVERage Limit CALCulate LIMit BURSt FERRor MAXimum Limit This command sets or queries the average or maximum center frequency error limit determined by the default WLAN measurement For details on the center frequency error results and the default WLAN measurement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Limit numeric value in Hertz Default unit HZ CALCulate LIMit BURSt IQOFfset AVERage Limit CALCulate LIMit BURSt IQOFfset MAXimum Limit This command sets or queries the average or maximum UO offset error limit determined by the default WLAN measurement For details on the UO offset and the default WLAN measu
279. ots for Tracking In case tracking is used the used pilot sequence has an effect on the measurement results This function is not available for IEEE 802 11b or g DSSS According to standard The pilot sequence is determined according to the corresponding WLAN standard In case the pilot generation algorithm of the device under test DUT has a problem the non standard conform pilot sequence might affect the measurement results or the WLAN applica tion might not synchronize at all onto the signal generated by the DUT Detected The pilot sequence detected in the WLAN signal to be analyzed is used by the WLAN application In case the pilot generation algorithm of the device under test DUT has a problem the non standard conform pilot sequence will not affect the measurement results In case the pilot sequence generated by the DUT is correct it is recommended that you use the According to Standard setting because it generates more accurate measurement results Remote command SENSe TRACking PILots on page 162 Demodulation The demodulation settings define which PPDUs are to be analyzed thus they define a logical filter The available demodulation settings vary depending on the selected digital standard in the Signal Description see Standard on page 72 e Demodulation IEEE 802 11a g OFDM cerent e 93 e Demodulation IEEE GO Ia 96 e Demodulation IEEE 802 11b g DS 101 e JDemodulation IEEE 802 1
280. pass filter for RF input signals from 1 GHz to 3 GHz This filter is used to remove the harmonics of the R amp S FSW in order to measure the harmonics for a DUT for example This function requires option R amp S FSW B13 Note for RF input signals outside the specified range the high pass filter has no effect For signals with a frequency of approximately 4 GHz upwards the harmonics are sup pressed sufficiently by the YIG filter Remote command INPut FILTer HPASs STATe on page 142 YIG Preselector Activates or deactivates the YIG preselector An internal YIG preselector at the input of the R amp S FSW ensures that image frequencies are rejected However the YIG filter may limit the bandwidth of the I Q data and will add some magnitude and phase distortions You can check the impact in the Spectrum Flat ness and Group Delay result displays SSS TR SSS SSS User Manual 1173 9357 02 06 74 R amp S FSW K91 Configuration a O HUR INR ENG WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Note that the YIG preselector is active only on frequencies greater than 8 GHz Therefore switching the YIG preselector on or off has no effect if the frequency is below that value Remote command INPut FILTer YIG STATe on page 143 5 3 4 2 Output Settings The R amp S FSW can provide output to special connectors f
281. pe before another trigger event occurs TT User Manual 1173 9357 02 06 63 R amp SS9FSW K91 Measurement Basics Deeg Triggered measurements Example In the following example the second possible trigger event is ignored as the signal does not exceed the hysteresis threshold before it reaches the trigger level again on the rising edge On the falling edge however two trigger events occur as the signal exceeds the hysteresis before it falls to the trigger level the second time Trigger level Fig 4 3 Effects of the trigger hysteresis See Hysteresis on page 89 4 8 3 Trigger Drop Out Time If a modulated signal is instable and produces occassional drop outs during a burst you can define a minimum duration that the input signal must stay below the trigger level before triggering again This is called the drop out time Defining a dropout time helps you stabilize triggering when the analyzer is triggering on undesired events T Pd F Drop Out Fig 4 4 Effect of the trigger drop out time See Drop Out Time on page 88 User Manual 1173 9357 02 06 64 Triggered measurements 4 8 4 Trigger Holdoff The trigger holdoff defines a waiting period before the next trigger after the current one will be recognized Frame 1 Frame 2 1 Holdoff Fig 4 5 Effect of the trigger holdoff See Trigger Holdoff on page 89 R amp S FSW K91 Configuration Multiple Measureme
282. pending on which standards the communicating devices are using different formats of PPDUs are availa ble Thus you can restrict analysis to the supported formats Note The PPDU format determines the available channel bandwidths For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display Format column see Signal Field on page 35 Auto same type as first PPDU A1st The format of the first valid PPDU is detected and subsequent PPDUs are analyzed only if they have the same format Auto individually for each PPDU AI All PPDUs are analyzed regardless of their format Meas only M Only PPDUs with the specified format are analyzed FERRE RU EA I T e e A LLLLLLLLLLLLL LALLLLLSL User Manual 1173 9357 02 06 97 R amp S FSW K91 Configuration REESEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Demod all as D All PPDUs are assumed to have the specified PPDU format Remote command SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 SENSe DEMod FORMat BANalyze on page 168 Channel Bandwidth to measure CBW Defines the channel bandwidth of the PPDUs taking part in the analysis Depending on which standards the communicating devices are using different PPDU formats and
283. play Information A dialog box opens that contains all operating modes and applications currently available on your R amp S FSW 2 Select the WLAN item gt WLAN The R amp S FSW opens a new measurement channel for the WLAN application The measurement is started immediately with the default settings It can be configured in the WLAN Overview dialog box which is displayed when you select the Overview softkey from any menu see chapter 5 3 2 Configuration Overview on page 70 2 2 Understanding the Display Information The following figure shows a measurement diagram during analyzer operation All infor mation areas are labeled They are explained in more detail in the following sections MultiView 33 Spectrum WLAN Sampling Rate Fs 320 0 MHz Standard IEEE 802 11ac Capt Time No of Samples 5ms 1 PPDU MCS Index GI Meas Setup 1 Tx X 1 Rx No of Data Symbols SGL Analyzed PPDUs 1 Magnitude Capture 2 I Clmw 6 Spectrum Flatness 1 Avg 2 Cirw 3Result Summary Global Bt irsts Min e 0 0s 4 5 0 ms Carrier 250 50 L Garmmer Carrier 250 2 Constellation 1 Clow 4 EVM vs Symbol oF Min Avg Max 5S EVM vs Carrier Symb 570 Carrier 250 50 1 Carrier 1 Channel bar for firmware and measurement settings 2 Window title bar with diagram specific trace information 3 Diagram area with marker information 4 Diagram footer with diagram specific information depending on result display 5 Instrumen
284. plication a new measurement channel is created which deter mines the measurement settings for that application These settings include the input Source the type of data to be processed I Q or RF data frequency and level settings measurement functions etc If you want to perform the same measurement but with dif ferent center frequencies for instance or process the same input data with different measurement functions there are two ways to do so e Change the settings in the measurement channel for each measurement scenario In this case the results of each measurement are updated each time you change the settings and you cannot compare them or analyze them together without storing them on an external medium e Activate a new measurement channel for the same application In the latter case the two measurement scenarios with their different settings are displayed simultaneously in separate tabs and you can either switch between the tabs or select the MultiView tab to compare the results User Manual 1173 9357 02 06 66 R amp S FSW K91 Configuration i Multiple Measurement Channels and Sequencer Function For example you can activate one WLAN measurement channel to perform a WLAN modulation accuracy measurement and a second channel to perform an SEM mea surement using the same WLAN input source The number of channels that can be configured at the same time depends on the available memory on the instrument Only one me
285. ported ERREUR E N User Manual 1173 9357 02 06 143 R amp SS9FSW K91 Remote Commands for WLAN Measurements NEA CI J J Qn Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Tip The I Q data to be analyzed for WLAN 802 11 can not only be measured by the WLAN application itself it can also be imported to the application provided it has the correct format Furthermore the analyzed IO data from the WLAN application can be exported for further analysis in external applications See chapter 5 3 13 Import Export Functions on page 114 Parameters Source RF Radio Frequency RF INPUT connector RST RF Manual operation See Radio Frequency State on page 74 9 5 2 2 Configuring the Outputs Configuring trigger input output is described in Configuring the Trigger Output on page 158 DIAGnoslic SERVIES NSO UWS acs 1 1a Iason tena esent vata D cnkec avt nae e a xi ccn peu aieea 144 DIAGnostic SERVice NSOurce State This command turns the 28 V supply of the BNC connector labeled NOISE SOURCE CONTROL on the front panel on and off For details see chapter 4 6 2 Input from Noise Sources on page 61 Parameters State ON OFF RST OFF Example DIAG SERV NSO ON Manual operation See Noise Source on page 75 9 5 3 Frontend Configuration The following commands configure frequency amplitude and y axis scali
286. pplication All general instrument functions and settings common to all applications and operating modes are described in the main R amp S FSW User Manual The main focus in this manual is on the measurement results and the tasks required to obtain them The following topics are included chapter 2 Welcome to the WLAN Application on page 9 Introduction to and getting familiar with the application chapter 3 Measurements and Result Displays on page 13 Details on supported measurements and their result types e chapter 4 Measurement Basics on page 45 Background information on basic terms and principles in the context of the measure ment e chapter 5 Configuration on page 66 and chapter 6 Analysis on page 119 A concise description of all functions and settings available to configure measure ments and analyze results with their corresponding remote control command e chapter 5 3 13 Import Export Functions on page 114 Description of general functions to import and export raw UO measurement data e chapter 7 How to Perform Measurements in the WLAN Application on page 120 The basic procedure to perform each measurement and step by step instructions for more complex tasks or alternative methods e chapter 8 Optimizing and Troubleshooting the Measurement on page 123 Hints and tips on how to handle errors and optimize the test setup chapter 9 Remote Commands for WLAN Measurements on page 126 Remote command
287. quency Sweep Measure ED The commands to retrieve results from frequency sweep measurements for WLAN sig ments on page 206 e PPDU and Symbol Count Results iniii teret och SAAR 198 e ErorParanmieterResults ice eec Ce dee 199 e Limit Check Results 203 9 9 1 1 PPDU and Symbol Count Results The following commands are required to retrieve PPDU and symbol count results from the WLAN IQ measurement on the captured UO data see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 ee ee ee Ge seca a 198 FETCHB BRSECOUNEALELS eta cise cossactceceuesvenieasetadicesedeneetedncvestaeviceadeaeveteadecacaccs 198 FETCH S diste re BI rr EM EUR 198 PET CBU bz cigar UC 199 FETCh BURSt COUNt This command returns the number of analyzed PPDUS from the current capture buffer If multiple measurements are required because the number of PPDUS to analyze is greater than the number of PPDUs that can be captured in one buffer this command only returns the number of captured PPDUs in the current capture buffer as opposed to FETCh BURSt COUNt ALL Usage Query only FETCh BURSt COUNt ALL This command returns the number of analyzed PPDUs for the entire measurement If multiple measurements are required because the number of PPDUs to analyze is greater than the number of PPDUs that can be captured in one buffer this command returns the number of analyzed PPDUs in a measurements as oppos
288. rameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only CALCulate LIMit BURSt IQOFfset AVERage RESult CALCulate LIMit BURSt IQOFfset MAXimum RESult This command returns the result of the average or maximum UO offset limit check The limit value is defined by the standard or the user see CALCulate LIMit BURSt IQOFfset MAXimum on page 180 Return values LimitCheck PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only CALCulate LIMit BURSt SYMBolerror AVERage RESult CALCulate LIMit BURSt SYMBolerror MAXimum RESult This command returns the result of the average or maximum symbol clock error limit check The limit value is defined by the standard or the user see CALCulate LIMit BURSt SYMBolerror MAXimum on page 180 eae User Manual 1173 9357 02 06 205 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 9 2 Retrieving Results Return values lt LimitCheck gt PASS The defined limit for the parameter was not exceeded FAILED The defined limit for the parameter was exceeded Usage Query only Numeric Results for Frequency Sweep Measurements The following commands are required to retrieve the numeric results of the WLAN fre quency sweep measurements see chapter 3 2 Frequency Sweep Measurements on page 39 In the following commands used to retrieve the
289. ration See RF Attenuation on page 81 See Attenuation Mode Value on page 81 INPut ATTenuation AUTO lt State gt This command couples or decouples the attenuation to the reference level Thus when the reference level is changed the R amp S FSW determines the signal level for optimal internal data processing and sets the required attenuation accordingly Parameters lt State gt ON OFF 0 1 RST 1 ERREUR EA N User Manual 1173 9357 02 06 148 R amp SS9FSW K91 Remote Commands for WLAN Measurements EEG EE CDI AC g 1 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Example INP ATT AUTO ON Couples the attenuation to the reference level Usage SCPI confirmed Manual operation See RF Attenuation on page 81 See Attenuation Mode Value on page 81 INPut EATT lt Attenuation gt This command defines an electronic attenuation manually Automatic mode must be switched off INP EATT AUTO OFF see INPut EATT AUTO on page 149 If the current reference level is not compatible with an attenuation that has been set manually the command also adjusts the reference level This command is only available with option R amp S FSW B25 It is not available if R amp S FSW B17 is active Parameters lt Attenuation gt attenuation in dB Range see data sheet Increment 1 dB RST
290. re available You can use a preamplifier to analyze signals from DUTs with low input power Off Deactivates the preamplifier 15 dB The RF input signal is amplified by about 15 dB 30 dB The RF input signal is amplified by about 30 dB Remote command INPut GAIN STATe on page 150 INPut GAIN VALue on page 150 Signal Capture Data Acquisition You can define how much and how data is captured from the input signal e General Capture SSDUngs EE 82 e Trigger Sette EE 84 General Capture Settings The general capture settings define how much and which data is to be captured during the WLAN IQ measurement ERREUR EA N User Manual 1173 9357 02 06 82 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Input Sample Rate Capture Time Swap IQ Filter Filter out Adjacent Channels Input Sample Rate This is the sample rate the R amp S FSW WLAN application expects the UO input data to have If necessary the R amp S FSW has to resample the data During data processing in the R amp S FSW the sample rate usually changes decreases The RF input is captured by the R amp S FSW using a high sample rate and is resampled before it is processed by the R amp S FSW WLAN application Remote command TRACe IQ SRATe on page 152 Capture Time Specifies the duration and therefore the amount of data to be captured in the capture buffer If the capture time is too sho
291. rement see chapter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Limit Range 1000000 to 1000000 Default unit DB CALCulate LIMit BURSt SYMBolerror AVERage Limit CALCulate LIMit BURSt SYMBolerror MAXimum Limit This command sets or queries the average or maximum symbol clock error limit deter mined by the default WLAN measurement For details on the symbol clock error and the default WLAN measurement see chap ter 3 1 1 Modulation Accuracy Flatness and Tolerance Parameters on page 13 Parameters Limit numeric value in parts per million Default unit PPM Automatic Settings GQONFigure POV AT Osean e nere rettet Re Der ree Ren ee hee aae tetra Rae 181 CONFiguire POWerAUTOSSWEen HIM e 11 idee tac ca dedo karen ede te tees 181 SENSe TADJustCONFigure DURalion 22 3 ie rte to cree ear a 181 T User Manual 1173 9357 02 06 180 R amp SS9FSW K91 Remote Commands for WLAN Measurements r OC n UO sr Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe ADJust CONFigure DURation MODE isses nennen 182 IGENGelADlust CONEioure Hv teresle LOMer na 182 SENSe ABJust CONFigure HYS Teresis UPP r arri ees etienne eben nut c niens 183 SENSE JAD Just LEVE pnia a a a Ion no ad ee neg ue Pre vn aa aai 183 CONFigure POW
292. ring the noise level of an amplifier In this case you can first connect an external noise source whose noise power level is known in advance to the R amp S FSW and measure the total noise power From this value you can determine the noise power of the R amp S FSW Then when you measure the power level of the actual DUT you can deduct the known noise level from the total power to obtain the power level of the DUT The noise source is controlled in the Output settings see Noise Source on page 75 4 6 3 Receiving and Providing Trigger Signals Using one of the variable TRIGGER INPUT OUTPUT connectors of the R amp S FSW the R amp S FSW can use a signal from an external reference as a trigger to capture data Alter natively the internal trigger signal used by the R amp S FSW can be output for use by other connected devices Using the same trigger on several devices is useful to synchronize the transmitted and received signals within a measurement For details on the connectors see the R amp S FSW Getting Started manual Ee User Manual 1173 9357 02 06 61 R amp S9FSW K91 Measurement Basics 4 7 Preparing the R amp S FSW for the Expected Input Signal Frontend Parameters External trigger as input If the trigger signal for the R amp S FSW is provided by an external reference the reference signal source must be connected to the R amp S FSW and the trigger source must be defined as External on the R amp S FSW Trig
293. ror Messages and VVarihiijs iececa arnica co ae i iain dee sd ac Rs 124 8 1 Optimizing the Measurement Results If the results do not meet your expectations try the following methods to optimize the measurement Improving Fertorepee META 123 e Improving Channel Estimation and EVM Accuracn 123 8 1 1 Improving Performance Performing a coarse burst search For signals with low duty cycle rates enable the Power Interval Search for synchro nization see Power Interval Search on page 91 In this case the R amp S FSW WLAN application initially performs a coarse burst search on the input signal in which increases in the power vs time trace are detected Further time consuming processing is then only performed where bursts are assumed This improves the measurement speed However for signals in which the PPDU power levels differ significantly this option should be disabled as otherwise some PPDUs may not be detected 8 1 2 Improving Channel Estimation and EVM Accuracy The channels in the WLAN signal are estimated based on the expected input signal description and the information provided by the PPDUs themselves The more accurate the channel estimation the more accurate the EVM based on these channels can be calculated Increasing the basis for channel estimation The more information that can be used to estimate the channels the more accurate the results For measurements that need not be performed strictly according to th
294. rrr nakin 111 Items to display remote as Result display cte er detnr det vaste Trace E rentrer terreni 212 Retrieving Numeric results remote ssssesss 198 Results remote sss RF Results remote ss Trace results remote ssssssssssssss 210 RF attenuation Auto SOTIKGy iecit ere eter te hinted 81 Manual softkey oriire 81 niagis m PC 73 Overload protection is Overload protection remote sssss 142 FROM OG ci sees 142 143 RF measurements ANALYSIS EI A NER M 119 Configuration remote sss 184 Results remote EST Step By step uiui erret norte eri ir ree tcd RF Power Een 87 Trigger level remote sssessssssss 156 RUN CONT ACC EIER 113 RUN SINGLE S Sample rate ce rete e ertt e tenen Definition DISPLAY OO Em MAXIMUM rr Relationship to bandwidth Sen Ee Samples e It EE 14 15 Saving fe e ET 114 Select MEAS oiii nmn ioter atian 66 SEM Configuring cdma2000 sss 116 Results Sequencer Aborting remote sess Activating remote T MOS ses Mode remote A Remote Softkey SUAS Settings ur
295. rs RST ALL CONF WLAN GTIM AUTO TYPE DL See Guard Interval Length on page 101 CONFigure WLAN GTIMe SELect lt GuardTime gt This remote control command specifies the guard time the PPDUs in the IEEE 802 11n or ac input signal should have If the guard time is specified to be detected from the input signal using the CONFigure WLAN GTIMe AUTO command then this command is query only and allows the detected guard time to be obtained User Manual 1173 9357 02 06 165 R amp S9FSW K91 Remote Commands for WLAN Measurements EAM X HP H Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters GuardTime Example Manual operation SHORt NORMal SHORt Only the PPDUs with short guard interval are analyzed NORMal Only the PPDUs with long guard interval are analyzed Long in manual operation RST NORMal CONF WLAN GTIM SEL SHOR See Guard Interval Length on page 101 CONFigure WLAN STBC AUTO TYPE lt PPDUType gt This remote control command specifies which PPDUs are analyzed according to STBC streams for IEEE 802 11n ac standards only Parameters lt PPDUType gt Example Manual operation FBURst ALL MO M1 M2 DO D1 D2 FBURst The STBC of the first PPDU is detected and subsequent PPDUs are analyzed only if they have the same STBC corresponds t
296. rt demodulation will fail Remote command SENSe SWEep TIME on page 152 Swap UO Activates or deactivates the inverted UO modulation If the and Q parts of the signal from the DUT are interchanged the R amp S FSW can do the same to compensate for it On and Q signals are interchanged Inverted sideband Ou Off and Q signals are not interchanged Normal sideband I j Q Remote command SENSe SWAPig on page 151 User Manual 1173 9357 02 06 83 R amp S FSW K91 Configuration a NR RENS WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Suppressing Filter out Adjacent Channels IEEE 802 11A G OFDM AC N If activated default only the useful signal is analyzed all signal data in adjacent chan nels is removed by the filter This setting improves the signal to noise ratio and thus the EVM results for signals with strong or a large number of adjacent channels However for some measurements infor mation on the effects of adjacent channels on the measured signal may be of interest Remote command SENSe BANDwidth RESolution FILTer STATe on page 151 5 3 5 2 Trigger Settings Trigger settings determine when the R amp S FSW starts to capture the input signal Trigger settings can be configured via the TRIG key or in the Trigger dialog box which is displayed when you select the Trigger button in the Overview rigger Trigger Source Trigger In
297. s Boolean Boolean parameters represent two states The ON state logically true is represented by ON or a numeric value 1 The OFF state logically untrue is represented by OFF or the numeric value 0 Querying boolean parameters When you query boolean parameters the system returns either the value 1 ON or the value 0 OFF Example Setting DISPlay WINDow ZOOM STATe ON Query DISPlay WINDow ZOOM STATe would return 1 Character Data Character data follows the syntactic rules of keywords You can enter text using a short or a long form For more information see chapter 9 2 2 Long and Short Form on page 128 Querying text parameters When you query text parameters the system returns its short form Example Setting SENSe BANDwidth RESolution TYPE NORMal Query SENSe BANDwidth RESolution TYPE would return NORM Character Strings Strings are alphanumeric characters They have to be in straight quotation marks You can use a single quotation mark or a double quotation mark Example INSTRument DELete Spectrum Block Data Block data is a format which is suitable for the transmission of large amounts of data The ASCII character introduces the data block The next number indicates how many of the following digits describe the length of the data block In the example the 4 following digits indicate the length to be 5168 bytes The data bytes follow Duri
298. s In case the pilot sequence generated by the DUT is cor rect it is recommended that you use the According to Stand ard setting because it generates more accurate measurement results RST STANdard Manual operation See Pilots for Tracking on page 93 LEE User Manual 1173 9357 02 06 162 R amp S FSW K91 Remote Commands for WLAN Measurements El Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe TRACking TIME State Activates or deactivates the compensation for timing drift If activated the measurement results are compensated for timing error on a per symbol basis Parameters State ON OFF RST OFF Manual operation See Timing Error Tracking on page 92 9 5 7 Demodulation The demodulation settings define which PPDUs are to be analyzed thus they define a logical filter The available demodulation settings vary depending on the selected digital standard see CONFigure STANdard on page 141 Manual configuration is described in chapter 5 3 8 Demodulation on page 93 CONFigure WLANEX tension AUTO TYPE EE 163 E Le HEEN EN EE 164 CONFIgure WLAN GTIMS AU e RE 164 CONFigure WLAN GTIMe SELaolt 2 2 ice entretien nna kane e ansia ER Ra RENE 165 CONFIgure WLAN STBGOAAUTO TYBE suite aa etu cen UR aaa a E AAA Ra cMe Eu cnRa 166 SENSe BANDwidth CHANnel AUTO TYPE eessesssesssssieee enhn nn nennt shes ntn nn na 166 SENSe DEMod FORMa
299. s Ness see Extension Spatial Streams sounding on page 107 CRC Cyclic redundancy code of bits 0 23 in HT SIG1 and bits 0 9 in HT SIG2 Tail Bits Used to terminate the trellis of the convolution coder Set to 0 The values for the individual demodulation parameters are described in chapter 5 3 8 Demodulation on page 93 The following abbreviations are used in the Signal Field table Table 3 8 Abbreviations for demodulation parameters shown in Signal Field display Abbreviation in Signal Parameter in Demodulation settings Field display Aist Auto same type as first PPDU Al Auto individual for each PPDU M lt x gt Meas only the specified PPDUs lt x gt D lt x gt Demod all with specified parameter lt y gt The Signal Field measurement indicates certain inconsistencies in the signal or discrep ancies between the demodulation settings and the signal to be analyzed In both cases an appropriate warning is displayed and the results for the PPDU are highlighted orange both in the Signal Field display and the Magnitude Capture display If the signal was analyzed with warnings the results indicated by a message also contribute to the overall analysis results User Manual 1173 9357 02 06 37 R amp S FSW K91 Measurements and Result Displays REESEN WLAN UO Measurement Modulation Accuracy Flatness and Tolerance PPDUs detected in the signal that do not pass the
300. s are analyzed according to their individual Nsts corresponds to Auto individually for each PPDU MEASure Only PPDUs with the Nsts specified by SENSe DEMod FORMat NSTSindex are analyzed DEMod The Nsts index specified by SENSe DEMod FORMat NSTSindexis used for all PPDUs RST FBURst Example SENS DEM FORM NSTS MODE MEAS SENS DEM FORM NSTS 1 Manual operation See Nsts to use on page 99 Evaluation Range The evaluation range defines which data is evaluated in the result display Note that as opposed to manual operation the PPDUs to be analyzed can be defined either by the number of data symbols the number of data bytes or the measurement duration CONFIS BURSEPVIPAVERAGC iissc55c02siaaeeaneezsda Fes aeu i ene ENNER Red 173 GCONFigure BURSEPVT RPOWher iceeeeeie entere bht nenne nna da ren RR AR Ra nkn REENEN NEEN 173 CONFigure ER NEE RR E RE 173 GONFigure WLAN PVERroOEMRANGge eege tenet eee eee eee anata 173 SENSE BUS COUN fS 174 RENSE ee EE 174 ISENGe JDEMod FORMatBANalvzeD vlesEOUa nennen 174 SENSe DEMod FORMat BANalyze DBYTes MAX isses nnne enne nnne 175 SENSe DEMod FORMat BANalyze DBYTes MIN esee nennen 175 SENSe DEMod FORMat BANalyze DURation EQUal eese 175 ISENGe IDEMod FORMatBANalvze DUlbRaton MAN 176 SENSe DEMod FORMat BANalyze DURation MIN eeeseeeeeee enne 176 SENSe D
301. s required to configure and perform WLAN measurements in a remote environment sorted by tasks Commands required to set up the environment or to perform common tasks on the instrument are provided in the main R amp S FSW User Manual Programming examples demonstrate the use of many commands and can usually be executed directly for test purposes chapter A Annex Reference on page 230 Reference material e List of remote commands Alpahabetical list of all remote commands described in the manual e Index User Manual 1173 9357 02 06 5 R amp SS9FSW K91 Preface Documentation Overview 1 2 Documentation Overview The user documentation for the R amp S FSW consists of the following parts e Getting Started printed manual e Online Help system on the instrument e Documentation CD ROM with Getting Started User Manuals for base unit and options Service Manual Release Notes Data sheet and product brochures Online Help The Online Help is embedded in the instrument s firmware It offers quick context sen sitive access to the complete information needed for operation and programming Online help is available using the icon on the toolbar of the R amp S FSW Getting Started This manual is delivered with the instrument in printed form and in PDF format on the CD It provides the information needed to set up and start working with the instrument Basic operations and handling are described Saf
302. s to Analyze on page 109 lt x gt PPDUs of totally required lt y gt PPDUs have been analyzed so far lt z gt PPDUs were analyzed in the most recent sweep In addition the channel bar also displays information on instrument settings that affect the measurement results even though this is not immediately apparent from the display of the measured values e g transducer or trigger settings This information is displayed only when applicable for the current measurement For details see the R amp S FSW Getting Started manual Window title bar information For each diagram the header provides the following information 2 Magnitude Capture 1 Clrw OGO Fig 2 1 Window title bar information in the WLAN application 1 Window number 2 Window type 3 Trace color 4 Trace number 6 Trace mode Diagram footer information The diagram footer beneath the diagram contains the start and stop values for the dis played x axis range E T User Manual 1173 9357 02 06 11 Understanding the Display Information Status bar information Global instrument settings the instrument status and any irregularities are indicated in the status bar beneath the diagram Furthermore the progress of the current operation is displayed in the status bar Click on a displayed warning or error message to obtain more details see also R amp S FSW K91 Measurements and Result Displays WLAN UO Measurement Modulation Accuracy
303. s you want the measurement to start only when a specific condition is fulfilled for example a signal level is exceeded or in certain time intervals For these cases you can define a trigger for the measurement In FFT sweep mode the trigger defines when the data acquisition starts for the FFT conversion An Offset can be defined to delay the measurement after the trigger event or to include data before the actual trigger event in time domain measurements pre trigger offset For complex tasks advanced trigger settings are available e Hysteresis to avoid unwanted trigger events caused by noise e Holdoff to define exactly which trigger event will cause the trigger in a jittering signal Mute Ten E 63 ERR ele E EE 63 e Trigger Drop OUE TIT eere retener er ence n retenta i rer iud eed dea 64 EE Loquo A E E E T E 65 4 8 1 Trigger Offset An offset can be defined to delay the measurement after the trigger event or to include data before the actual trigger event in time domain measurements pre trigger offset Pre trigger offsets are possible because the R amp S FSW captures data continuously in the time domain even before the trigger occurs See Trigger Offset on page 88 4 8 2 Trigger Hysteresis Setting a hysteresis for the trigger helps avoid unwanted trigger events caused by noise for example The hysteresis is a threshold to the trigger level that the signal must fall below on a rising slope or rise above on a falling slo
304. sOUEGtonablellMitcnz P Ransttion nennen nnne nennen entente 228 STATusOUEG onable L MitznzfTEVENUN enne eene nennen eene nennen 226 EN el ee ER VC HE D 227 STATus QUEStionable PTRansition STATusOUEG onable GvNC CGONDiton ika ea Eedeni kaana aaia kadandan 227 STATusOUEG onable GNCENADile eterne nnne tnet rnnt tne teen nnns nennen eeen 227 SGTATusOUEG onable GvNCN Tanson 227 STATusOUEG onable GvhNC P Ransition eene nnns nnns 228 STATus QUEStionable SYNC EVENE cc cccssccescecsssecsseecsseasesncesseceaeeeeesacersaseseaeeesacessasaseaeeeeseeesneasseees 226 STATus QUEStionable EVENt STATus QUEuUS NEXT 5 rar E rere ERR TTE eevee agence ee FEES 226 SvGfemPRE Ger CHANnell ENECutel eterne tenentis sete rnnn sinas 135 SY ER ee 196 TRACelODATAMEMonm nennen eterne nentes etre nnd seres ier nn sers innen erre nenne sens s sen nr erre sensns nlis 212 EEUU RU SSS 5 User Manual 1173 9357 02 06 244 R amp S FSW K91 List of Remote Commands WLAN TRAC SOS RAT lE 152 RRE KRAN EE 210 iRAGesn DATA X ciii rettescte tese iter Podio si rep edge shee p dae uice e Cei lese beca RSEN 212 TRIGger SEQuence LEVel POWer AUT Q rrt tnr dna tiun den x eia a iR ee 155 TRIGger SEQuence DTIM uto ter erp ee pepe neurones iar e PEE Eed TRIGger SEQuence HOLDOoff TIME 5 6 rrt tn hunt inne ern enint nante tbe en dois TRIGger SEQuence IFPower HOLDoff TRIGger SEQuence IFPower HYS Teresis
305. see OUTPut TRIGger port LEVel RST DEVice See Trigger 2 3 on page 76 See Output Type on page 76 OUTPut TRIGger lt port gt PULSe IMMediate This command generates a pulse at the trigger output Suffix lt port gt 2 3 Selects the trigger port to which the output is sent 2 trigger port 2 front 3 trigger port 3 rear User Manual 1173 9357 02 06 159 R amp SS9FSW K91 Remote Commands for WLAN Measurements REAEMECAC UI C S u mee m Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Usage Event Manual operation See Trigger 2 3 on page 76 See Output Type on page 76 See Send Trigger on page 77 OUTPut TRIGger lt port gt PULSe LENGth Length This command defines the length of the pulse generated at the trigger output Suffix port 2 3 Selects the trigger port to which the output is sent 2 trigger port 2 front 3 trigger port 3 rear Parameters Length Pulse length in seconds Manual operation See Trigger 2 3 on page 76 See Output Type on page 76 See Pulse Length on page 76 9 5 5 Synchronization and OFDM Demodulation I SENS amp DEMOQ FET OPESGL terrore ere teret bre pete oer treten ele e ANNIE EEN Tiaa eii 160 SEN Se DEMO TAARE D 161 SENSe DEMod FFT OFFSet lt Mode gt This comman
306. seeenaes 124 Remote Commands for WLAN Measurements 126 Common Suffixes nicer ceci censectececedsceczaesvascecaesceasceceagseasedzaceseatte 126 Introduction itte tert ASEA 127 Activating WLAN Measurements eeesseeeeeeneen nennen nennen nnn rnnt nnns 132 Selecting a Measurement esee eene nennen nennen nnne nnne nnn nnn 136 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tol rupe M 141 Configuring Frequency Sweep Measurements on WLAN Signals 184 Configuring the Result Display esee nnne 184 Starting a Measurement eese eene eene nennen nne nennen nnn 193 Remieving Results sonrasi m 197 EIN EEN Status e UC 224 Commands for Compatibility ecce nennen nennen nnn 228 Pure 0 e 230 Sample Rate and Maximum Usable UO Bandwidth for RF Input 230 UO Data File Format iq tar eeseeeeeeeeeeeeeeeeeeneenenennenenn nennen 234 List of Remote Commands WLAN eene 241 j P 247 User Manual 1173 9357 02 06 4 R amp SS9FSW K91 Preface About this Manual 1 Preface 1 1 About this Manual This WLAN User Manual provides all the information specific to the a
307. specified are analyzed MCS M ee User Manual 1173 9357 02 06 98 R amp S FSW K91 Configuration REENEN WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Demod all with The MCS Index setting is used for all PPDUs specified MCS D Remote command SENSe DEMod FORMat MCSindex MODE on page 170 MCS Index Defines the MCS index of the PPDUs taking part in the analysis manually This field is enabled for MCS index to use Meas only the specified MCS or Demod all with specified MCS Remote command SENSe DEMod FORMat MCSindex on page 170 Nsts to use Defines the the PPDUS taking part in the analysis depending on their Nsts Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display NSTS column see Signal Field on page 35 Auto same All PPDUS using the Nsts identical to the first recognized PPDU are type as first analyzed PPDU A1st Auto individ All PPDUs are analyzed ually for each PPDU Al Meas only the Only PPDUs with the Nsts specified for the Nsts on page 99 setting specified are analyzed Nsts M Demod all with The Nsts on page 99 setting is used for all PPDUs specified Nsts D Remote command SENSe DEMod FORMat NSTSindex MODE on page 171 Nsts Defines the Nsts of the PPDUs taking part in the analysis This fie
308. st valid PPDU is detected and subse quent PPDUs are analyzed only if they have the same format Auto individually for each PPDU All PPDUs are analyzed regardless of their format modulation Meas only Only PPDUs with the specified format or PSDUs with the specified modulation are analyzed User Manual 1173 9357 02 06 102 R amp S FSW K91 Configuration 5 3 8 4 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Demod all as All PPDUs are assumed to have the specified PPDU format PSDU modulation Remote command SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 SENSe DEMod FORMat BANalyze on page 168 PPDU Format If analysis is restricted to PPDUs with a particular format see PPDU Format to mea sure PSDU Modulation to use this setting defines which type For details on supported modulation depending on the standard see table 4 1 Remote command SENSe DEMod FORMat BANalyze on page 168 PSDU Modulation If analysis is restricted to PSDU with a particular modulation type this setting defines which type For details on supported modulation depending on the standard see table 4 1 Remote command SENSe DEMod FORMat BANalyze on page 168 Demodulation IEEE 802 11n The following settings are available for demodulation of IEEE 802 11n signals Demodulation PDUs to Analyze PPDU Analysis Mode Auto same type as firs
309. t 9 signal gain Af frequency deviation between Tx and Rx symbol index 1 nof_Symbols nof_symbols number of symbols of payload H channel transfer function of subcarrier k k channel index k 7 31 32 Kod modulation dependent normalization factor g relative clock error of reference oscillator DA subcarrier of symbol I e Block Diagram for Multicarrier Measurements esses 45 e Literature on the IEEE 802 11a Standard cnet 52 4 1 1 Block Diagram for Multicarrier Measurements A diagram of the significant blocks when using the IEEE 802 11a or g OFDM standard in the R amp S FSW WLAN application is shown in figure 4 1 First the RF signal is downconverted to the IF frequency fic The resulting IF signal rei is shown on the left hand side of the figure After bandpass filtering the signal is sampled by an analog to digital converter ADC at a sample rate oft This digital sequence is resampled Thus the sample rate of the downsampled sequence r i is the Nyquist rate of f 20 MHz Up to this point the digital part is implemented in an ASIC ERREUR EA a User Manual 1173 9357 02 06 45 R amp S FSW K91 Measurement Basics Signal Processing for Multicarrier Measurements IEEE 802 11a g OFDM ra o 2 S S SOE S 8 o SZ z 41 f 20MHz 6 AA D 4 Ha 16 pilots data channel estimation E 20 cm Resampier
310. t BANAlyZe 0 0 cceeeeeeeeeeeee cece eaee nennen nennen nsns estate eren rnit nens 168 SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE sess nnhnn nnne 169 ISENSeIDEMod FORMatt BCONiengt AUTO 170 SENSe DEMod FORMatMGOSiIndex 2 ee tret nad eee Rene miim re aa R qe on anb dag inns 170 SENSe DEMod FORMat MCSindex MODE eeesssessessessesen nennen nnne nh nnn nnn 170 SENSeJDEMod FORMACINS TSIDGBX ire iina SSES Ed ENEE 171 SENSe DEMod FORMatNSTSindex MODE 2 22 cootra du cnn thao ehe ainia 171 CONFigure WLAN EXTension AUTO TYPE lt PPDUType gt Defines the PPDUS taking part in the analysis according to the Ness Extension Spatial Streams field content for IEEE 802 11n standard only User Manual 1173 9357 02 06 163 R amp S9FSW K91 Remote Commands for WLAN Measurements HEEMETAEMM C H A mI m 5 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Parameters lt PPDUType gt Example Manual operation FBURst ALL MO M1 M2 M3 DO D1 D2 D3 The first PPDU is analyzed and subsequent PPDUs are analyzed only if they match FBURst The Ness field contents of the first PPDU is detected and subse quent PPDUs are analyzed only if they have the same Ness field contents corresponds to Auto same type as first PPDU ALL All recognized PPDUs are analyzed according to the
311. t PPDU D for each property to analyze PPDU Format to measure Auto same type as first PPDU gt Channel Bandwidth to measure Auto same type as first PPDU up to CBW160 MHz MCS Index to use Auto same type as first PPDU MCS Index Nsts to use Auto same type as first PPDU Nsts STBC Field Auto same type as first PPDU Data Rate Mb s 800ns GI 400ns GI QPSK 58 5 65 Modulation Guard Interval Length Fig 5 4 Demodulation settings for IEEE 802 11n standard EE User Manual 1173 9357 02 06 103 R amp S FSW K91 Configuration a 8 WLAN IQ Measurement Modulation Accuracy Flatness Tolerance PPDU Analysis E 104 PPDU Format to THEISEN 104 Channel Bandwidth to measure CBW cincti ecce nee tae e ek e nua sa uL v d nh aaa 105 MOS Index to USO I o te rite rt er a rne iue nha deter agudo 105 jer Em 106 STB PICMG c 106 Extension Spatial Streams sounding ener tnn tinh in ndis 107 Table info EE 107 Guard Interval eri EEN 107 PPDU Analysis Mode Defines whether all or only specific PPDUS are to be analyzed Auto same type as first PPDU The signal symbol field i e the PLCP header field of the first recog nized PPDU is analyzed to determine the details of the PPDU All PPDUS identical to the first recognized PPDU are analyzed All subsequent settings are set to Auto mode Auto individually for each PPDU All PPDUs are analyzed
312. t adaptation due to small changes in the input signal you can define a hysteresis This setting defines a lower threshold the signal must fall below compared to the last measurement before the reference level is adapted auto matically Parameters Threshold Range O dB to 200 dB RST 1dB Default unit dB Example SENS ADJ CONF HYST LOW 2 For an input signal level of currently 20 dBm the reference level will only be adjusted when the signal level falls below 18 dBm E A User Manual 1173 9357 02 06 182 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 5 11 Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Manual operation See Lower Level Hysteresis on page 112 SENSe JADJust CONFigure HYSTeresis UPPer Threshold When the reference level is adjusted automatically using the SENSe ADJust LEVel on page 183 command the internal attenuators and the preamplifier are also adjusted In order to avoid frequent adaptation due to small changes in the input signal you can define a hysteresis This setting defines an upper threshold the signal must exceed compared to the last measurement before the reference level is adapted auto matically Parameters lt Threshold gt Range 0 dB to 200 dB RST 1dB Default unit dB Example SENS ADJ CONF HYST UPP 2 Example For an input signal level of currently 20 dBm the reference level will only be adjusted w
313. t indi vidual sweeps RUN SINGLE starts the Sequencer in single mode If the Sequencer is off only the evaluation for the currently displayed measurement channel is updated Remote command INITiate IMMediate on page 194 Continue Single Sweep While the measurement is running the Continue Single Sweep softkey and the RUN SINGLE key are highlighted The running measurement can be aborted by selecting the highlighted softkey or key again DERE RU N User Manual 1173 9357 02 06 113 R amp S FSW K91 5 3 13 E 0 5 4 Configuration Frequency Sweep Measurements Import Export Functions The following import and export functions are available via softkeys in the Save Recall menu which is displayed when you select the Save or Open icon in the toolbar For a description of the other functions in the Save Recall menu see the R amp S FSW User Manual EKDOM E 114 ENER eeneg 114 lues C 114 lui 114 Export Opens a submenu to configure data export IQ Export Export Opens a file selection dialog box to select an export file to which the IQ data will be stored This function is only available in single sweep mode and only in applications that process UO data such as the UO Analyzer or optional applications For details see chapter 5 3 13 Import Export Functions on page 114 Remote command MMEMory STOR
314. t port gt LEVel on page 158 Pulse Length Output Type Trigger 2 3 Defines the length of the pulse sent as a trigger to the output connector Remote command OUTPut TRIGger lt port gt PULSe LENGth on page 160 Send Trigger Output Type Trigger 2 3 Sends a user defined trigger to the output connector immediately Note that the trigger pulse level is always opposite to the constant signal level defined by the output Level setting e g for Level High a constant high signal is output to the connector until the Send Trigger button is selected Then a low pulse is sent Which pulse level will be sent is indicated by a graphic on the button Remote command OUTPut TRIGger lt port gt PULSe IMMediate on page 159 Synchronization and OFDM Demodulation Synchronization settings have an effect on which parts of the input signal are processed during the WLAN measurement T User Manual 1173 9357 02 06 90 R amp S FSW K91 Configuration WLAN IQ Measurement Modulation Accuracy Flatness Tolerance Synchronization Power Interval Search OFDM Demodulation Power Interval Seabbli teo sce tec i code Cer teen ed eve eoo testes ue ein ede Ese ndede ced 91 FEET SUPE EE 91 Power Interval Search If enabled the R amp S FSW WLAN application initially performs a coarse burst search on the input signal in which increases in the power vs time trace are detected Further time consuming processin
315. t status bar with error messages progress bar and date time display Channel bar information In the WLAN application the R amp S FSW shows the following settings FE User Manual 1173 9357 02 06 10 R amp S FSW K91 Welcome to the WLAN Application aS eS a ee ee ee ee Understanding the Display Information Table 2 1 Information displayed in the channel bar in the WLAN application Label Description Sample Rate Fs Input sample rate PPDU MCS Index GI WLAN 802 1 1a ac n The PPDU type MCS Index and Guard Interval used for the analysis of the signal Depending on the demodulation settings these values are either detected automatically from the signal or the user settings are applied PPDU Data Rate WLAN 802 1 1b The PPDU type and data rate used for the analysis of the signal Depending on the demodulation settings these values are either detected automatically from the signal or the user settings are applied Standard Selected WLAN measurement standard Meas Setup Number of Transmitter Tx and Receiver Rx channels used in the mea surement currently always 1 Tx 1 Rx Capt time No of Samples Duration of signal capture and number of samples captured No of Data Symbols The minimum and maximum number of data symbols that a PPDU may have if it is to be considered in results analysis Analyzed PPDUs x of y z For statistical evaluation over PPDUs see PPDU Statistic Count No of PPDU
316. t works as an output RST INPut Manual operation See Trigger 2 3 on page 76 OUTPut TRIGger lt port gt LEVel Level This command defines the level of the signal generated at the trigger output This command works only if you have selected a user defined output with OUTPut TERIGgereport OTYPe T User Manual 1173 9357 02 06 158 R amp S9FSW K91 Remote Commands for WLAN Measurements EMEN F m I H Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance Suffix port Parameters Level Manual operation 2 3 Selects the trigger port to which the output is sent 2 trigger port 2 front 3 trigger port 3 rear HIGH TTL signal LOW OV RST LOW See Trigger 2 3 on page 76 See Output Type on page 76 See Level on page 76 OUTPut TRIGger lt port gt OTYPe lt OutputType gt This command selects the type of signal generated at the trigger output Suffix lt port gt Parameters lt OutputType gt Manual operation 2 3 Selects the trigger port to which the output is sent 2 trigger port 2 front 3 trigger port 3 rear DEVice Sends a trigger signal when the R amp S FSW has triggered internally TARMed Sends a trigger signal when the trigger is armed and ready for an external trigger event UDEFined Sends a user defined trigger signal For more information
317. tep get 120 Parameters s is oie eade oa phe pa erede nerd 13 Remote control 126 RESUS m Q 13 Y YIG preselector Activating Deactivating sss 74 Activating Deactivating remote 143 IBI IU eege E E SAS AN 69 Z Zooming Activating remote ss sss Area Multiple mode remote Se Area emote cei cerent dente te Seed gert tee Multiple mode remote suusss Remote Single mode remote sees
318. ters 9 11 1 e The STATus QUEStionable SYNC Registel 2 ccceeceeecceeteeeeeeneeeeeeeneeeees 224 e Querying the Status Registers 2 2 ccccecceeeccsececceeeesnntedeceeeeedaatedeceeesananenceeeees 225 The STATus QUEStionable SYNC Register The STATus QUEStionable SYNC register contains application specific information about synchronization errors or errors during pilot symbol detection If any errors occur in this register the status bit 11 in the STATus QUEStionable register is set to 1 ERREUR E MN User Manual 1173 9357 02 06 224 R amp S9FSW K91 Remote Commands for WLAN Measurements Status Registers Each active channel uses a separate STATus QUEStionable SYNC register Thus if the status bit 11 in the STATus QUEStionable register indicates an error the error may have occurred in any of the channel specific STATus QUEStionable SYNC reg isters In this case you must check the register of each channel to determine which channel caused the error By default querying the status of a register always returns the result for the currently selected channel However you can specify any other channel name as a query parameter Table 9 15 Meaning of the bits used in the STATus QUEStionable SYNC register Bit No Meaning 0 PPDU not found This bit is set if an IQ measurement is performed and no PPDUS are detected 1 This bit is not used 2
319. titions of the PPDU These corrections can be switched off individually in the demodula tion settings of the application T User Manual 1173 9357 02 06 53 Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS uoneums3 joquikg uoneulns3 uoneuins3 uonewnsy ules Spur baly Bui peuornnied peuonnied peuonnieg uonejjejsuo jeubisg sjueuuredui OI WAS sua OWEJeg le Jo uoneuns 3 uoneuins3 Jet Jejusuei uajdwesey uo 9e0D Buri Bueyi4 uonoeuo u0I 284102 1 fiequ pueqeseg ules eseyd bai4 uoneuins3 J8j I4 J841928M uoneuins 3 uogeuins3 eseug bai But y AO i T I 19 duiesey uonoe4102 uonoeu0 eseug baly mid ZHWrr S Ps AO f Jeyngejduies sisunguouees aqe ou uf Jeynq eunjdeo Oj 1940 SiSAjeuy aJd Fig 4 2 Signal processing for IEEE 802 11b or g DSSS signals R amp SS9FSW K91 Measurement Basics Signal Processing for Single Carrier Measurements IEEE 802 11b g DSSS Once the the normalized and undisturbed reference signal is available the transmitter baseband filter Tx filter is estimated by minimizing the cost function of a maximum likelinood based estimator N 1 uu PE M 2 pc gt r v x e P xe _ yh i x S v i 0 jog v 0 i L Transmitter baseband filter Tx filter estimation 4 9 where r v the oversampled measurement signal S v the normalized oversampled power of the undisturbed reference signal N
320. trum gt IQ Histogram width 64 height 64 gt 0123456789 0 lt Histogram gt IQ lt Channel gt lt ArrayOfChannel gt lt PreviewData gt A 2 2 Q Data Binary File The UO data is saved in binary format according to the format and data type specified in the XML file see Format element and DataType element To allow reading and writing of streamed I Q data all data is interleaved i e complex values are interleaved pairs of and Q values and multi channel signals contain interleaved complex samples for R amp SS9FSW K91 Annex Reference EE UO Data File Format iq tar channel 0 channel 1 channel 2 etc If the NumberOfChannels element is not defined one channel is presumed Example Element order for real data 1 channel I 0 Real sample 0 I 1 Real sample 1 R 2 Real sample 2 Example Element order for complex cartesian data 1 channel I 0 Q 0 Real and imaginary part of complex sample 0 I 1 Q 1 Real and imaginary part of complex sample 1 I 2 QI21 Real and imaginary part of complex sample 2 Example Element order for complex polar data 1 channel Mag 0 Phi 0 Magnitude and phase part of complex sample 0 Mag 1 Phi ll Magnitude and phase part of complex sample 1 Mag 2 Phi 2 Magnitude and phase part of complex sample 2 Example Element order for complex cartesian data 3 channels Complex data I channel no time index Q channel no time
321. ubcarrier Nyseq 1 2 1 Minimum EVM nusea EVM2 nused pres EVMstatistic Length Nused H Minimum EVM value for subcarrier Nuseq 1 2 FFT Spectrum Returns the power vs frequency values obtained from the FFT This is an exhaustive call due to the fact that there are nearly always more FFT points than UO samples The num ber of FFT points is a power of 2 that is higher than the total number of UO samples Le number of FFT points round number of I Q samples to next power of 2 E g if there were 20000 samples then 32768 FFT points are returned Data is returned in floating point format in dBm Group Delay Currently the following trace types are provided with this measurement e TRACEL A repeating list of group delay values for each subcarrier The number of repeating lists corresponds to the number of fully analyzed PPDUs as displayed in the current Magnitude Capture Each group delay value is returned as a floating point number expressed in units of seconds e TRACE All group delay values per subcarrier for each analyzed PPDU of the capture period LEES User Manual 1173 9357 02 06 218 R amp S9FSW K91 Remote Commands for WLAN Measurements ELEME H H A Pw Retrieving Results Example For GDmn the group delay of the m th analyzed PPDU for the subcarrier corresponding to n 1 2 Nusea Y TRACE DATA TRACE2 Analyzed
322. ult Display Note that the suffix n always refers to the window in the currently selected measure ment channel see INSTrument SELect on page 135 IR FORM mec 185 DISPlaypWIMDowsrns E 185 DISPlay FORMat Format This command determines which tab is displayed Parameters Format SPLit Displays the MultiView tab with an overview of all active channels SINGIe Displays the measurement channel that was previously focused RST SPL Example DISP FORM SING DISPlay WINDow lt n gt SIZE Size This command maximizes the size of the selected result display window temporarily To change the size of several windows on the screen permanently use the LAY SPL com mand see LAYout SPLitter on page 189 Parameters Size LARGe Maximizes the selected window to full screen Other windows are still active in the background SMALI Reduces the size of the selected window to its original size If more than one measurement window was displayed originally these are visible again RST SMALI Example DISP WIND2 LARG 9 7 2 Working with Windows in the Display The following commands are required to change the evaluation type and rearrange the screen layout for a measurement channel as you do using the SmartGrid in manual operation Since the available evaluation types depend on the selected application some parameters for the following commands also depend on the selected measurement channel Note that the suff
323. ummary CDMA 2000 Channel Bandwidth Offset Power R 229 MHz 0 86 dBm 0 86 dBm 79 59 dB 80 34 dp 85 04 dB 83 85 dB Upper For details see chapter 5 4 1 Channel Power ACLR Measurements on page 115 Remote command CONFigure BURSt SPECtrum ACPR IMMediate on page 140 Querying results CALC MARK FUNC POW RES ACP see CALCulate MARKer FUNCtion POWer RESult on page 207 Spectrum Emission Mask The Spectrum Emission Mask SEM measurement determines the power of the WLAN signal in defined offsets from the carrier and compares the power values with a spectral mask specified by the WLAN 802 11 specifications The limits depend on the selected bandclass Thus the performance of the DUT can be tested and the emissions and their distance to the limit be identified Note The WLAN 802 11 standard does not distinguish between spurious and spectral emissions For details see chapter 5 4 2 Spectrum Emission Mask on page 116 ERREUR RA T i e 1 1 L ALLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLX User Manual 1173 9357 02 06 40 R amp S FSW K91 Measurements and Result Displays Ref Level 41 00 dBm Offset 40 00 dB Mode Auto Sweep Limit Check 31 lt P lt 39 Span 25 5 MHz 2 Result Summary W CDMA 3GPP DL Tx Power 33 74 dBm Tx Bandwidth 3 840 MHz RBW 1 000 MHz Range Low Range Up Frequency Power Abs Power Rel ALimit 12 750 MHz 8 000 MHz 00 MHz 2 09153 GHz 39 37 dBm 73 11 dB 18 61 dB 8 000 MHz M
324. ured for Input in the Outputs con figuration see Trigger 2 3 on page 76 External Trigger 3 Trigger signal from the TRIGGER 3 INPUT OUTPUT connector on the rear panel Note Connector must be configured for Input in the Outputs con figuration see Trigger 2 3 on page 76 Remote command TRIG SOUR EXT TRIG SOUR EXT2 TRIG SOUR EXT3 See TRIGger SEQuence SOURce on page 156 IF Power Trigger Source Trigger Source Settings The R amp S FSW starts capturing data as soon as the trigger level is exceeded around the third intermediate frequency This trigger source is only available for RF input For frequency sweeps the third IF represents the start frequency The trigger bandwidth at the third IF depends on the RBW and sweep type For measurements on a fixed frequency e g zero span or UO measurements the third IF represents the center frequency T User Manual 1173 9357 02 06 86 R amp S FSW K91 Configuration 8 uie WLAN IQ Measurement Modulation Accuracy Flatness Tolerance The available trigger levels depend on the RF attenuation and preamplification A refer ence level offset if defined is also considered For details on available trigger levels and trigger bandwidths see the data sheet Remote command TRIG SOUR IFP see TRIGger SEQuence SOURce on page 156 UO Power Trigger Source Trigger Source Settings This trigger source is not available if the
325. ut GAIN STATe on page 150 The command requires option R amp S FSW B24 Parameters Gain Example Usage Manual operation 15 dB 30 dB The availability of preamplification levels depends on the R amp S FSW model R amp S FSWS8 15dB and 30 dB R amp S FSW13 15dB and 30 dB R amp S FSW26 30 dB All other values are rounded to the nearest of these two RST OFF INP GAIN VAL 30 Switches on 30 dB preamplification SCPI confirmed See Input Settings on page 82 See Preamplifier option B24 on page 82 INPut GAIN STATe State This command turns the preamplifier on and off The command requires option R amp S FSW B24 Parameters State Example Usage Manual operation ON OFF RST OFF INP GAIN STAT ON Switches on 30 dB preamplification SCPI confirmed See Input Settings on page 82 See Preamplifier option B24 on page 82 User Manual 1173 9357 02 06 150 R amp SS9FSW K91 Remote Commands for WLAN Measurements REAEMEECAECIMCCOI CCI S i Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance 9 5 4 Signal Capturing The following commands are required to configure how much and how data is captured from the input signal e General Capture Settings 0 6 ccccceccccecsceccdecsneedecesegaedeceeeaanadeeeeduautecesaaaeceess 151 e Configuring Triggered Measureme
326. v Sjuejsuoo pejejaua Buruui 9 0z age Gel ZLOZ LL 208 PIS dal H ZS 0 L ER atz 22 123 D zg v9 0c ULL SJojeureJed pojej aJ Buru G 9 age qe ZLOZ LI 209 PIS dal LL Co 0 L eg c Le v 9r v9 oz SJojeureJed pojejaJ Buru G 9 age Gel ZLOZ L1 208 PIS dal LL Co 0 L eg c Le v 9r v9 0L SJojeureJed pojej aJ Buru G 9 age qe ZLOZ LL 209 PIS dal LL CO 0 L eS c Le D 9r v9 fe ELL dENA INN Ais N os JINN 0301 ISN 9S Jon a os 9s JojId os ejep pesny 14 P SN Jo ON Jeoqgns JO ON Jo ON 40 ON Jo ON ZHIN DIER jueuluio JN P N PasnN INN 9G INN SN 9s a esqns zolid ZEN HEN HIN M99 uejs ujeuiop Aouanbay ay ui eunjonags joquiAs WHO NV 1M ZL 6 2 9eL User Manual 1173 9357 02 06 Remote Commands for WLAN Measurements R amp S9FSW K91 Retrieving Results 96 zc uonenbe ZLOZ ue L Za 22 rzogd 3331 9 S6 zc uonenbe Z OZ YJE L za oer rzogd 3331 s 6 ZZ uonenbe Z OZ YEW L za oer Lzogd 3331 p 6S 0Z uonenbe zL0z L1 z08 PIS 3331 sJeuueoqns jolld 0L0L zz uonoes ZLOZ YEW L za oer l zogd 3331 Z sJeuueoqns jolld 0L LL 0z uonoes ZLOZ L L208 PIS 3331 4 671 BZ ZZL g L g ETE Sjuejs EI i lez L 291 bel Gi u09 peje jeJ Buiuil G zz 9Iqe oct 68 CG Sc GZ 9 68 LIL ZLOZ YOUEW L ZQ eL L zogd 3331 LL LOS 6ZL ZL 8p 6 L L9L 0c LEZ 94 99r ZLS 094 Sjuejs u09 pe1ejaJ Buiuui G z
327. vM olerrort AVERaoel RE Gu 205 CALCulate LIMiEESK FAIL rrt che reet rene tne pfe dade don he e ree Ren 207 CAL CulateMAbkerEUNGCon POWer RE Gut 207 CAL Culate STA Tis cs RESUS V sei erra eren redeo pu ter rana etaa eiai eren ra bes 209 jer E Culate lt n gt MARKGRSM gt qu AEAEE DARN 209 CAL Culatesn MARKoersm Y9 iui corna coe ertt e ti ach ed ta ed ebur re dote expe khe dea ke dea dede Pee Ee DER dees 221 CALCulate lt n gt MARKer lt m gt STATe CAL Culate cnz UNITT POWer estne nenne then nnn nnns ein nrts sein tesieiitini ssi tine sisi tens siet nts n nnns ennan CONFigure BURSt CONSt CCARrier MMediate esee 137 CONFigure BURSt CONSt CSYMbol IMMediate esee enne 137 CONFigure BURSt EVM ECARrier IMMediate eese nennen 137 CONFioure BURGCEVM ECHmotlMMedtatel nennen neret 137 CONFioure BURGCEVMEGvMboll IMMediatel ennemis 137 CONFigure BURSt EVM ESYMbol IMMediate IEEE 802 11b and g Den 137 CONFigure BURSEPV T AVERG e rro etie treten orienter ke cr od p sates aces Te i rra ek en enses Yo dna Rao 173 WEE Tt UE Ee AA E 173 CONFigure BURSEtPVT IMM ediate eene enne nnn then rnnt knee eaten rai snae en as 138 Ee User Manual 1173 9357 02 06 241 R amp S FSW K91 List of Remote Commands WLAN CONFigure BURSt SPECtrum ACPR IMMediate esee eene 140 CONFigure
328. valuation method you want to add See the table below for available parameter values Return values lt NewWindowName gt When adding a new window the command returns its name by default the same as its number as a result Example LAY ADD 1 LEFT MTAB Result 2 Adds a new window named 2 with a marker table to the left of window 1 Usage Query only T User Manual 1173 9357 02 06 186 R amp S FSW K91 Remote Commands for WLAN Measurements Manual operation Configuring the Result Display See Bitstream on page 22 See Constellation on page 24 See Constellation vs Carrier on page 25 See EVM vs Carrier on page 26 See EVM vs Chip on page 27 See EVM vs Symbol on page 27 See FFT Spectrum on page 28 See Group Delay on page 29 See Magnitude Capture on page 29 See PLCP Header IEEE 802 11b g GSSS on page 30 See PvT Full PPDU on page 31 See Result Summary Detailed on page 32 See Result Summary Global on page 33 See Signal Field on page 35 See Spectrum Flatness on page 38 See Diagram on page 43 See Result Summary on page 43 See Marker Table on page 43 See Marker Peak List on page 44 Table 9 6 lt WindowType gt parameter values for WLAN application Parameter value Window type Window types for I Q data BITStream CMEMory Bitstream Magnitude Capture CONStellation Constellation CVCarrier Constellation vs Carrier
329. w 1 at the top of the screen and the selected result type in window 2 below that MMEMory LOAD E REN VE 228 ISENGe IDEMod FORMatBANalvzeBivbe nnne nnns 229 Tislogen SEQuense BE 229 MMEMory LOAD SEM STATe 1 Filename This command loads a spectrum emission mask setup from an xml file Note that this command is maintained for compatibility reasons only Use the SENS ESP PRES command for new remote control programs EEUU EA T User Manual 1173 9357 02 06 228 R amp SS9FSW K91 Remote Commands for WLAN Measurements Commands for Compatibility See the R amp S FSW User Manual Remote commands for SEM measurements chapter Parameters 1 Filename string Path and name of the xm1 file that contains the SEM setup infor mation Example MMEM LOAD SEM STAT 1 sem_std WLAN 802 11aN802 11a 10MHz 5GHz band XML SENSe DEMod FORMat BANalyze BTYPe lt PPDUType gt This remote control command specifies the type of PPDU to be analyzed Only PPDUs of the specified type take part in measurement analysis Note that this command is maintained for compatibility reasons only Use the specified commands for new remote control programs see SENSe DEMod FORMat BANalyze BTYPe AUTO TYPE on page 169 and SENSe BANDwidth CHANnel AUTO TYPE on page 166 Parameters lt PPDUType gt MM20 IEEE 802 11n Mixed Mode 20 MHz sampling rate For new programs use SENSe DE
330. width of the PPDUs taking part in the analysis Depending on which standards the communicating devices are using different PPDU formats and channel bandwidths are supported For details on supported PPDU formats and channel bandwidths depending on the standard see table 4 1 Note The terms in brackets in the following description indicate how the setting is refer red to in the Signal Field result display CBW column see Signal Field on page 35 Auto same The channel bandwidth of the first valid PPDU is detected and subse type as first quent PPDUs are analyzed only if they have the same channel band PPDU Aist width Auto individu All PPDUs are analyzed regardless of their channel bandwidth ally for each PPDU AI Meas only Only PPDUs with the specified channel bandwidth are analyzed signal M Demod all All PPDUs are assumed to have the specified channel bandwidth as sig nal D Remote command SENSe BANDwidth CHANnel AUTO TYPE on page 166 PSDU Modulation to use Specifies which PSDUs are to be analyzed depending on their modulation Only PSDUs using the selected modulation are considered in measurement analysis For details on supported modulation depending on the standard see table 4 1 Auto same All PSDUS using the same modulation as the first recognized PPDU are type as first analyzed PPDU A1st N User Manual 1173 9357 02 06 95 R amp S FSW K91 Configurati
331. y error includes the frequency error of the R amp S FSW and that of the DUT If possible the transmitterR amp S FSW and the DUT should be synchronized using an external reference See R amp S FSW User Manual gt Instrument setup gt External reference Chip clock error ppm Clock error between the signal and the chip clock of the R amp S FSW in parts per million ppm i e the chip timing error the corresponding limits specified in the standard are also indicated If possible the transmitterR amp S FSW and the DUT should be synchronized using an external reference See R amp S FSW User Manual gt Instrument setup gt External reference Rise time Time the signal needs to increase its power level from 1096 to 9096 of the max imum or the average power depending on the reference power setting The corresponding limits specified in the standard are also indicated Fall time Time the signal needs to decrease its power level from 9096 to 1096 of the max imum or the average power depending on the reference power setting The corresponding limits specified in the standard are also indicated Mean power dBm Mean PPDU power Peak power dBm Peak PPDU power Crest factor dB The ratio of the peak power to the mean power of the PPDU also called Peak to Average Power Ratio PAPR The R amp S FSW WLAN application also performs statistical evaluation over several PPDUs and displays
332. z jqeL AEOL SZ ZLOZ YOUEW L Za oeL L zogd 3331 LL GYZ si 013 E zz 6 LL LL 6e GZ 01 3 8 vec EE 08 dSN D NG TIAN E N os JINN IEIOL 1SN 9S Jeu ia os s jojId os ejep Fenn 1d pesn jo ON seoqns Jo ON Jo oN Jo ON Jo ON piep yu wwog JN Fy PP N INN 2G Ny ASN s 1e111e2qns zolid ZEN HEN HN M99 uejs 215 User Manual 1173 9357 02 06 R amp S9FSW K91 Remote Commands for WLAN Measurements 9 9 4 1 9 9 4 2 9 9 4 3 Retrieving Results GESEIS ege eege ege EE EENEG 216 e CCDF Complementary Cumulative Distribution Function 216 e CGS e EE 216 e Constellation VS CANTON treten es iva eet rre Fea eed Legen EE 217 e EVM Vs Gamer coste a cases et MI ete 218 LEE dE Cu DEE 218 e Group RTE Amt 218 e Power vs Time Full Burst ssseeseeeeeeene nennen nnne nennen nnns nnne a a 219 EE udo 219 e peotrum EE cde ete ee ete Yee t lan cial usb x aude a Ene rR Ne Gees ege 219 Bitstream Data is returned depending on the selected standard for which the measurement was executed see CONFigure STANdard on page 141 e Forthe IEEE 802 11a and n standard data is returned in repeating groups of 52 data channels or 56 channels within the n standard where each symbol value is repre sented by an integer value within one byte Channel 0 is unused and theref
333. ze DURation EQUal command is set to true then this command specifies the exact duration required for a PPDU to take part in measurement analysis If the SENSe DEMod FORMat BANalyze DURation EQUal command is set to false this command specifies the minimum duration required for a PPDU to take part in measurement analysis Parameters Duration RST 1 Default unit us Manual operation See Min Max Payload Length IEEE 802 11b g DSSS on page 110 ERREUR RA MN User Manual 1173 9357 02 06 176 R amp SS9FSW K91 Remote Commands for WLAN Measurements EEG ag u n Configuring the WLAN IQ Measurement Modulation Accuracy Flatness and Tolerance SENSe DEMod FORMat BANalyze SYMBols EQUal State For IEEE 802 11a g OFDM ac n signals only If enabled only PPDUs with a specific number of symbols are considered for measure ment analysis If disabled only PPDUs whose length is within a specified range are considered The number of symbols is specified by the SENSe DEMod FORMat BANalyze SYMBols MIN command A range of data symbols is defined as a minimum and maximum number of symbols the payload may contain see SENSe DEMod FORMat BANalyze SYMBols MAX on page 177 and SENSe DEMod FORMat BANalyze SYMBols MIN on page 177 Parameters State ON OFF RST OFF Manual operation See Equal

R&S FSW WLAN Application User Manual

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R&amp;S FSW WLAN Application User Manual

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R&S FSW WLAN Application User Manual