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K248 IEEE 802.11 (a/b/g)

1. FCS checksum FIET iic endo CC tetuer e roin es HL aer Filter Parameter ite enu Filter Type Filter GlippIFlg WEE Fix marker delay to current range 47 T3 Fixed Marker Delay Maximum Frame VE Frame Control srne tev errori vamus 35 84 G Generate WaverormiFlle eus corio coxa re tipo erae 23 Global Trigger Clock Settings eesseessse 49 l lden TOT eege 25 Increment CVE RY ac coercendi ETEY 37 85 86 Interleaver Active OFDM cccccccssseeceeeeessesteeeeeeees 33 53 L Load IEEE 802 11a g WLAN settings 23 58 M Man al Reie ET 67 Marker Delay AT 78 Marker Mode torio ren t cur iste ae 46 Measured external clock reete 49 KOENEN Ae 48 77 N Number of Data Symbols soidessa 31 87 Nolet filler eiie petra wea Ee 63 O AER cocti nre ito t ras ert e bes 24 53 54 ON OFF Ratio Marker niri trenes 46 75 P Paltl rti 2 irn rere evocare AEN 31 82 PBC O mode rnit ert terris 24 53 54 Physical Layer Mode 24 53 54 PLCP P H Format CCK PBCC uses 29 55 PPDU Configuration 2 eorr rr nnn 26 PRBS TY PGs inen retenti re ex P n i nh 31 Predefined Frames nns dEedeedeEde NEE 25 53 PSDU Bit Rate COK c M MHR PY 80 OFDM 2 90 OFDMPBCC es aa 80 PSDU Bit Rate CCK
2. Chip Rate Variation Enters the chip rate For each physical layer mode an own parameter is defined Which parameter is affected depends on the currently selected mode The chip rate entry changes the output clock and the modulation bandwidth as well as the synchronization signals that are output It does not affect the calculated chip sequence Remote command SOURce lt hw gt BB WLAN CRATe VARiation on page 66 Clipping Settings The settings for clipping are collected in the Clipping section Clipping State Switches baseband clipping on and off Baseband clipping is a very simple and effective way of reducing the crest factor of the WLAN signal WLAN signals may have high crest factors particularly in the 802 11a g OFDM mode High crest factors entail two basic problems The nonlinearity of the power amplifier compression causes intermodulation which expands the spectrum spectral regrowth Since the level in the D A converter is relative to the maximum value the average value is converted with a relatively low resolution This results in a high quantiza tion noise Both effects increase the adjacent channel power Trigger Marker Clock Settings With baseband clipping all the levels are limited to a settable value Clipping Level This level is specified as a percentage of the highest peak value Since clipping is done prior to filtering the procedure does not influence the spectrum Th
3. essent SOURce hw BB WLAN TRIGger OBASeband INHibit essent SOURce lt hw gt BB WLAN TRIGger OUTPut DELay FlXed TSOUlbce chws BB WAN TRlGoer OUT Putzchz DEL aw SOURce hw BB WLAN TRIGger OUTPut ch DELay MAXimum esses 73 SOURce hw BB WLAN TRIGger OUTPut ch DELay MlNimum eese 74 SOURce hw BB WLAN TRIGger OUTPut ch MODE eesssseeeeeeeeeeenee ener TEE AUNES 74 SOURce hw BB WLAN TRIGger OUTPut ch OFFTime essere 75 SOURce hw BB WLAN TRIGger OUTPut ch ONTime essere SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt PATTern SOURce hw BB WLAN TRIGger OUTPut ch PULSe DlVider senes 76 SOURce hw BB WLAN TRIGger OUTPut ch PULSe FREQuency esee 76 SOURce hw BB WLAN TRIGger RMODe eese nnne KERE PNEUEN EKET EANET 69 SOURcCeshw ErBB WEAN TRIGger SLENglh ccrta teet pet e op ee eee cep SOURC sliw BB WEAN TRIGGefE SEUNItL roit irr wuts EE EE SOURceshw gt BB WLAN TRIG GER SOURCGO coton tnt ra eene eer tt eR e Pere epe erp peek erneut SOURce lt hw gt BB WLAN TRIGger EXTernal lt ch gt DELay SOURce lt hw gt BB WLAN TRIGger EXTernal lt ch gt INHibit ESOURceshw gt EEN FR CT HME sccevesseresevsnnce 61 SOURce shw BB WLAN WAVeform CREale pe reten
4. BB WLAN PLCP FORMat on page 55 PPDU Sequence Configuration PSDU Bit Rate Selects the bit rate of the PSDU e OFDM All data rates defined by the standard are supported The selection of the PSDU bit rate automatically determines the code rate of the convolutional coder and the sub carrier modulation of the OFDM Data rate Possible modulation mode 6 and 9 Mbps BPSK 12 and 18 Mbps QPSK 24 and 36 Mbps 16 QAM 48 and 54 Mbps 64 QAM e CCK PBCC The data rates available are 1 Mbps 2 Mbps 5 5 Mbps 11 Mbps and 22 Mbps The 1 Mbps data rate is only available if the long PLCP format has been selected framed mode only The selection of the data rate also determines the possible modulation modes The following table shows the correlation between data rate and modulation Data rate Possible modulation mode 1 Mbps Barker Sequence DBPSK the information data sequence is spread with an 11 chip Barker sequence chip rate is 11 Mcps 2 Mbps Barker Sequence DQPSK the information data sequence is spread with an 11 chip Barker sequence chip rate is 11 Mcps 5 5 Mbps CCK DQPSK or PBCC BPSK 11 Mbps CCK DQPSK or PBCC QPSK 22 Mbps PBCC 8PSK Remote command SOURce lt hw gt BB MILAN PSDU BRATe on page 80 PSDU Modulation Indicates the modulation type PSDU Modu OFDM Indicates the modulation type used on the OFDM subcarri lation OFDM ers The m
5. The complete settings in the IEEE 802 11a g WLAN menu are saved and recalled Recall IEEE Opens the File Select window for loading a saved IEEE 802 11a g 802 11a g WLAN configuration WLAN setting The configuration of the selected highlighted file is loaded by press ing the Select button Save IEEE Opens the File Select window for saving the current IEEE 802 11a g 802 11a g WLAN signal configuration WLAN setting The name of the file is specified in the File name entry field the directory selected in the save into field The file is saved by pressing the Save button File Manager Calls the File Manager The File Manager is used to copy delete and rename files and to create new directories Remote command SOURce lt hw gt BB SOURce hw BB SOURce hw BB SOURce hw BB AN SETTing CATalog on page 57 AN SETTing LOAD on page 58 AN SETTing STORe on page 58 AN SETTing DELete on page 58 D UJ UJ UJ a zx zx S Generate Waveform File Calls the Generate Waveform menu This menu is used to store the current WLAN signal as ARB signal in a waveform file This file can be loaded in the ARB menu and processed as multicarrier or multiseg ment signal The file name is entered in the submenu The file is stored with the predefined file extension wv The file name and the directory it is stored in are user definable Remote command S
6. The data lists must be selected as a data source from the submenus under the individ ual function e g in the channel table of the cells Note All data lists are generated and edited by means of the SOURce BB DM subsys tem commands Files containing data lists usually end with dm iqd The data lists are selected as a data source for a specific function in the individual subsystems of the digital standard Remote command SOURce lt hw gt BB WLAN PSDU DATA on page 81 Scrambler OFDM Activates deactivates the scrambler and selects the mode of determining the initializa tion value OFF The scrambler is deactivated Random The scrambler is activated The initialization value of the scrambler is selected at random Each frame has a different random initialization value This value is also dif ferent in case of successive recalculations with the same setting parameters so that different signals are generated for each calcula tion User The scrambler is activated The initialization value of the scrambler is set to a fixed value that is entered at Scrambler Init hex This value is then identical in each generated frame Remote command SOURce hw BB WLAN SCRambler MODE on page 56 Scrambler CCK PBCC Activates or deactivates the scrambler Some tests require a test signal without scram bling e g for the RF carrier suppression measurement OFF The scrambler is deactivated ON Th
7. BB WLAN FILTer PARameter COSine lt Cosine gt The command sets the roll off factor for the Cosine filter type Parameters lt Cosine gt float Range 0 05 to 1 0 Increment 0 01 RST 0 1 Example BB WLAN PAR COS 0 35 sets the roll off factor to 0 35 for filter type Cosine Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt BB WLAN FILTer PARameter GAUSs lt Gauss gt The command sets the roll off factor for the Gauss filter type Parameters lt Gauss gt float Range 0 15 to 2 5 Increment 0 01 RST 0 5 Example BB WLAN PAR COS 0 5 sets B x T to 0 5 for the Gauss filter type Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt BB WLAN FILTer PARameter LPASs lt LPass gt The command sets the cut off frequency factor for the Lowpass filter ACP optimiza tion type Parameters lt LPass gt float Range 0 05 to 2 RST 0 5 Example BB WLAN FILT PAR LPAS 0 5 the cut of frequency factor is set to 0 5 Manual operation See Cut Off Frequency Factor on page 39 Filter Clipping Settings SOURce lt hw gt BB WLAN FILTer PARameter LPASSEVM lt LPassevm gt The command sets the cut off frequency factor for the Lowpass filter EVM optimiza tion type Parameters lt LPassevm gt float Range 0 05 to 2 0 RST 0 5 Example BB WLAN FILT PAR LPASSEVM 0 5 the cut of frequency factor is set to 0 5 Manual operation See Cut Off
8. In the last step the baseband signal is modulated onto the selected RF carrier and the complete signal is sent to the receiver via the air interface Operating Manual 1171 5283 12 15 13 2 2 2 2 1 2 2 2 Physical Layer CCK PBCC Physical Layer CCK PBCC A distinction is made between the packet type or PPDU format with long or short PLCP physical layer convergence protocol Long PLCP PPDU Format In 802 11 the data packet on the physical layer is referred to as PPDU PLCP protocol data units A PPDU consists of three components the PLCP preamble the PLCP header and the PSDU PLCP service data unit which contains the actual information data coming from higher layers The PLCP preamble and header are used for synchronization and signalling purposes and are themselves divided into fields The PLCP preamble consists of a synchronization field and a start frame delimiter field The standard specifies a fixed data content for both fields The PLCP header consists of the signal service length and CRC fields The signal field determines the data rate used in the PSDU field The rates 1 Mbps 2 Mbps 5 5 Mbps and 11 Mbps can be selected rates 22 MBps and 33 Mbps can be used in the optional PBCC modes The service field also helps to differentiate the modulation modes CCK or PBCC used for the higher data rates of 5 5 Mbps and 11 Mbps The length of the PSDU field is entered in us in the Length field The CRC f
9. NR gt e 5 1 1 Documentation OvervliGw ccce iiec niuis nna itur nna ONNAN NERKA N ANANE GONNE AYENA daran ea Ras 5 1 2 Conventions Used in the Documentation eene enn 6 CNN ee ele le Re e UE 6 1 22 Notes op Screenshots ti i one ter dee ui D a co X Rod e Ea Ld e ga 7 1 2 3 Naming of Software Optons nennen nentes nens 7 ST NIN eR a iaaea Eae ia 9 2 1 Physical Layer OFDM eerte mer cvaucaeeetesceceacerss sadeceeesquceesesvescte 10 2 0 NN PLOP FOMA cocotte tee e ette ten e eder be ied vns 11 2 1 2 le Gi ele 11 214 3 Signal Field DEE 12 E Usar E E M 12 2 2 Physical Layer CCK PBCC cccccsccseseeeeeeeeeeeseeeeneeeeesseeseesneeeeeseeseseeeeeeeeeeaneeseneeeeess 14 2 2 1 bong Pb CP PPDU Eottmal credere ta rn ree etu e tas verbs 14 2 22 Short PLCP PPDU Formal ttt re n e n Re d vie a Rn ERR RR 14 2 3 Data Spreading and Modulation CCK PBCC eese 15 2 3 1 1 Mbps Data Rate with DBPSK Modulation sse 16 2 3 2 2 Mbps Data Rate with DOPSK Modulatton eena 16 2 3 8 5 5 Mbps Data Rate with CCK Modulation aa 17 2 3 4 11 Mbps Data Rate with CCK Modulaton a 18 2 3 5 5 5 Mbps and 11 Mbps Data Rates with PBCC Modulaton 19 2 3 6 22 Mbps and 33 Mbps Data Rates with PBCC Modulaton n 19 3 WLAN User Interfaco eec ere tht n tnra nn naneknnncUe 21 3 1 General Settings for WL
10. Running Stopped For enabled modulation displays the status of signal generation for all trigger modes e Running The signal is generated a trigger was internally or externally initiated in triggered mode e Stopped The signal is not generated and the instrument waits for a trigger event Remote command SOURce lt hw gt BB WLAN TRIGger RMODe on page 69 Trigger Marker Clock Settings Arm For trigger modes Armed Auto and Armed Retrigger stops the signal generation until subsequent trigger event occurs Remote command SOURce hw BB WLAN TRIGger ARM EXECute on page 66 Execute Trigger This feature is available for Trigger Source Internal only Executes trigger manually A manual trigger can be executed only when an internal trigger source and a trigger mode other than Auto have been selected Remote command SOURce lt hw gt BB WLAN TRIGger EXECute on page 67 Trigger Source Selects trigger source This setting is effective when a trigger mode other than Auto has been selected e Internal The trigger event is executed by Execute Trigger Internal Baseband A B two path instruments The trigger event is the trigger signal from the second path e External Trigger 1 2 The trigger event is the active edge of an external trigger signal supplied at the TRIGGER 1 2 connector Use the Global Trigger Clock Settings dialog to define the polarity the trigger threshold and
11. which in the ideal case does not cause any intercarrier interference ICI CCK The CCK complementary code keying physical layer mode is used for the 5 5 Mbps and 11 Mbps data rates PBCC The PBCC packet binary convolutional coding physical layer can optionally be used instead of CCK modulation RST CCK BB WLAN MODE OFDM selects physical layer mode OFDM See Physical Layer Mode on page 24 SOURce lt hw gt BB WLAN PLCP FORMat Format The command selects the packet type PPDU format with long or short PLCP physi cal layer convergence protocol framed mode only Depending on the format selected the structure modulation and data rate of the PLCP preamble and header are modified The command is only available in framed mode SOURce BB WLAN SMODe FRAMed and for physical layer mode CCK and PBCC SOURce BB WLAN MODE CCK PBCC Parameters Format Example Manual operation LONG SHORt RST LONG BB WLAN PLCP FORM LONG selects the packet type PPDU format with long PLCP See PLCP P H Format CCK PBCC on page 29 SOURce lt hw gt BB WLAN PLCP LCBit STATe State The command sets the Locked Clock Bit in Service Field of the PLCP Header The command is only available in framed mode SOURce BB WLAN SMOD FRAMed and for physical layer mode CCK and PBCC SOURce BB WLAN MODE CCK PBCC General Commands Parameters State 0 1 OFF ON RST ON Example BB WLAN PLCP
12. 6 MHz Channel spacing 20 MHz The table shows the main parameters of OFDM 64 point IFFT is used to generate the 52 subcarriers 12 of the 64 possible carriers are not used One is the carrier in the middle of the band which would otherwise be impaired by the carrier leakage of the UO modulator the others are the remaining carriers at the upper and lower end of the spectrum The required subcarrier offset of 312 5 kHz is implicitly observed when the time signal generated by the IFFT with a sampling rate of 20 MHz is output These 20 MHz are also called kernel sample rate An OFDM symbol generated in this way would have a period of 3 2 us To compensate for multipath propagation a so called guard interval with a duration of 0 8 us is attached to each symbol so that a total sym bol interval of 4 us is obtained Either BPSK QPSK 16QAM or 64QAM modulation can be used on the subcarriers Prior to the modulation the raw data are convolutionally coded with code rates of 1 2 to being possible The frame structure can be seen in the figure below also indicated in the PPDU Con figuration dialog Coded OFDM Coded OFDM BPSK r 1 2 Rate is indicated in Signal PLCP Format The physical layer convergence protocol PLCP is a protocol layer between medium access control and the actual physical transmission layer PHY It is mainly used to adapt the different transmission formats of the 802 11 standards to the MAC layer w
13. BB WLAN TRIG OUTP2 MODE PULS enables the pulsed marker signal BB WLAN TRIG OUTP2 PULS FREQ queries the pulse frequency of the marker signal Response 33 000 the resulting pulse frequency is 33 kHz Usage Query only Manual operation See Marker Mode on page 46 4 5 Clock Settings This section lists the remote control commands necessary to configure the clock SOURce shw BB WLAN CLOCK MODE 2 essessseeseieiee nns en nnne sh nh nennen hene nnns TT SOURCe hw EBBIVLAN CEOCIMUL TiIpliei ata aie co rte Renten tte 77 SOURCce lt hw BBAWLAN CLOCK SOURGCG 2 2 sscececssedeiccecstessveccrectsnecateceteeaevenesaseeevents 78 LSOUbRcechwzslBBWL AN CLOCk SvNcChrontzaton ENtECute 78 SOURce lt hw gt BB WLAN CLOCk SYNChronization MODE eene 79 SOURce lt hw gt BB WLAN CLOCk MODE Mode The command enters the type of externally supplied clock BB WLAN CLOCk SOURce EXTernal When MCHip is used a multiple of the chip clock is supplied via the CLOCK connector and the chip clock is derived internally from this The multiplier is entered with the com mand SOURce hw BB WLAN CLOCk MULTiplier For two path instruments the only numerical suffix allowed for SOURce is 1 since the external clock source is permanently allocated to path A Parameters Mode CHIP MCHip RST CHIP Example BB WLAN CLOC MODE CHIP sele
14. FILTer PARameter APCOD25 essent nnne 63 SOURce hw BB WLAN FILTer PARameter COSine essen enne 64 SOURce hw BB WLAN FILTer PARameter GAUSS esses enne ee neret rennen 64 SOURceshw BB WLAN FIETer PARameter LPASS netta ttt trn bn nennen knit ene 64 SOURce hw BB WLAN FILTer PARameter LPASSEVM sess 65 SOURce hw BB WLAN FILTer PARameter PGAuss essent 65 SOURce lt hw gt BB WLAN FILTer PARameter RCOSine 549 TSOUlbce chwz BB WAN FI Terb bameter Gase 65 SOURceshw EBB WLAN FIET6r TYPE ce erret rh Ferr tre entrer rear rh nere trenes 63 SOURceshw T BB WEAN ILEawver STAT a thuris oto etes cech EO t beri eh exte ee Rer OIL BE ER ER Re cias 53 SOURceshw BB WLAN ITIM nio chen rnnt rete retenti te tr t thin inni er rhet reca 53 SOURceshw BB WLAN MODDB etn trc ener eter ere tec ett a PX EE een dha ue a ga 54 SOURceshw BB WEAN PEGP PORMAL ier n ari a eie tbe PX Y mr Rene dE DS 55 SOURce lt hw gt BB WLAN PLCP LCBit STATe sa DO Eeler ENEE ER terrere erro Hei reor e aA e na 56 ele e ER IR ER EEN 80 ISOUlbce chwz BB WAN PGDU BGbbeadmg GTATe nnne 80 SOURceshw BB WLAN PSDU DVATA neon tu roue tet ih rene ka rete ok ta t ner SEC en 81 SOURceshw BB WLAN PSDU DATA DSEL6ot 5 rnt tao ciento khen coh ke cr nha e kh Eaa 81 SOURce hw BB WLAN PSDU DATA PATTern esses neret nnneee neret e
15. Frequency Factor on page 39 SOURce lt hw gt BB WLAN FILTer PARameter PGAuss lt PGauss gt The command sets the roll off factor for filter type Pure Gauss Parameters lt PGauss gt float Range 0 15 to 2 5 RST 0 5 Example BB WLAN PAR PG 0 2 sets the roll off factor Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt BB WLAN FILTer PARameter RCOSine lt RCosine gt The command sets the roll off factor for the Root Cosine filter type Parameters lt RCosine gt float Range 0 to 1 0 Increment 0 01 RST 0 22 Example BB WLAN PAR RCOS 0 22 sets the roll off factor to 0 22 for filter type Root Cosine Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt BB WLAN FILTer PARameter SPHase lt SPhase gt The command sets B x T for the Split Phase filter type Parameters lt SPhase gt float Range 0 15 to 2 5 Increment 0 01 RST 2 4 3 Trigger Settings Example BB WLAN PAR SPH 0 5 sets B x T to 0 5 for the Split Phase filter type Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt BB WLAN CRATe VARiation Variation The command enters the output chip rate Parameters Variation float Range 1 kcps to 40 Mcps Increment 1 Hz RST 802 11a 20 Mcps 802 11b 11 Mcps 802 119 11 Mcps Example BB WLAN CRAT VAR 4086001 sets the output chip rate to 4 08 Mcps Manual operation See Chip Rate Va
16. PBCC getto etre 30 PSD BitRate OFDM ct neret treten 30 PSDU Data SOURCE ennt rtt ee 31 81 PSDU Modulation rrr rns 30 87 Pulse Divider Marker rotes 46 76 Pulse Frequency Marker tns 46 76 R Recall IEEE 802 11a g WLAN settings 23 58 Retrigger ROM OTE M ROW Oi Te E RUNNING eerie Running Trigger S Sampling Rate Variation 1 rere nnne 66 Save IEEE 802 11a g WLAN settings 23 58 Save Recall iiien pice Ste petes 23 SCHAMDIGH ssenariy oira Ma srr aenar aes 32 Scrambler Init hex OFDM 239 57 Scrambler OFDM 3 net rtc terreat nga 32 Scrambling OFDM nr eet rr tes 56 Sequence Configuration sessssessssss 26 Sequence Control 2 a eee Sequence E ET Sequence Length Trigger Service Field hex OFDM Service Field Clock Bits CCK PBCC 33 55 Set Synchronization Settings 48 78 Set to default 22 56 Signal Dutatiotr 2 rrt rrr renes 42 Signal Duration Unit Trigger eese 70 Simulation Mode 24 59 Single Duration Unit Trigger eese 69 iir infe le eere 23 60 Standard settings sssri 1 epe Le eoe 22 56 Start Number 97 85 86 State 22 State Clippin
17. PLCP pream 1 Mbps 11 Mcps 11 chip Barker DBPSK ble sequence Short PLCP header 2 Mbps 11 Mcps 11 chip Barker DQPSK sequence Long PLCP header 1 Mbps 11 Mcps 11 chip Barker DBPSK sequence PSDU 1 Mbps long 11 Mcps 11 chip Barker DBPSK PPDU sequence PSDU 2 Mbps 11 Mcps 11 chip Barker DQPSK sequence PSDU 5 5 Mbps 11 Mcps CCK DQPSK PSDU 11 Mbps 11 Mcps CCK DQPSK PSDU 5 5 Mbps 11 Mcps PBCC BPSK PSDU 11 Mbps 11 Mcps PBCC QPSK PSDU 22 Mbps 11 Mcps PBCC 8PSK PSDU 33 Mbps 16 5 Mcps PBCC 8PSK The individual combinations of spreading coding and modulation are described below 1 Mbps Data Rate with DBPSK Modulation At a data rate of 1 Mbps the already scrambled data stream is DBPSK modulated according to the table below The resulting symbol sequence is then spread using the 11 chip Barker sequence Bit input Phase change 0 0 2 Mbps Data Rate with DQPSK Modulation At a data rate of 2 Mbps the already scrambled data stream is DQPSK modulated according to the table below The resulting symbol sequence is then spread using the 11 chip Barker sequence Data Spreading and Modulation CCK PBCC Dibit pattern d0 d1 d0 is first in time Phase change 00 0 01 pi 2 11 pi 10 3pi 2 pi 2 2 3 3 5 5 Mbps Data Rate with CCK Modulation The standard specifies CCK modulation complementary code keying for a data rate of 5 5 Mbps To this end in each modulation step
18. control field The Frame control field has a length of 2 bytes 16 bits and is used to define the protocol version the frame type and its function etc As an alternative the individual bits can be set with the following commands The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt FControl gt integer Range H0000 16 to HFFFF 16 RST H0000 16 Example BB WLAN PSDU MAC FCON H100A 16 sets the value of the frame control field Manual operation See Frame Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC FCONtrol FDS lt Fds gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol MDATa lt Mdata gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol MFRagments lt Mfragments gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol ORDer lt Order gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol PMANagement lt Pmanagement gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol PVERsion lt PVersion gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol RETRy lt Retry gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol SUBType lt Subtype gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol TDS lt Tds gt SOURce lt hw gt BB WLAN PSDU MAC FCONtrol TYPE Type SOURce lt hw gt BB WLAN PSDU MAC FCONtrol WEP lt Wep gt The command enters the value of the individual bits of the frame control field The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Par
19. four successive bits d to d3 are taken from the data stream which is already scrambled The phases 1 2 3 Q4 are determined by these four bits Q4 is determined by the data bits dy and d according to the following table which specifies different phases for even and odd modulation steps Dibit pattern d0 d1 d0 is first Even symbols phase change Odd symbols phase change in time 00 0 pi 01 pi 2 3pi 2 pi 2 11 pi 0 10 3pi 2 pi 2 pi 2 The phase must be interpreted relative to the phase of the previous symbol The other three phases are determined as follows 2 d pi pi 2 957 0 47 d pi By means of these four phases the CCK code word can now be determined it is c e0 9 0 AP eiO 9 699 eJ X 20 JO Q eJ 9 20 oJ 9 oly Data Spreading and Modulation CCK PBCC Example do to d3 0110 the phase of the last symbol is 0 the current modulation step is even 947 pi 2 1 pi pi 2 3pi 2 957 0 Q47 O pi 0 The CCK code word is consequently C el Pi 2 3pi 2 0 0 gi pil2 3pi 2 0 gj pi 2 3pi 2 0 amp j pi 2 0 gi pi 2 3x 2 0 gj pi 2 0 gj pi 2 3pi 2 gipi 2V c e e ei e ei e ei 1 1 1 j 1 j 1 j The four data bits dg to d3 thus become the eight complex output chips co to c 2 3 4 11 Mbps Data Rate with CCK Modulation The standard also specifies CCK modulation complementary code keying for a dat
20. on page 57 Time Domain Windowing Active Activates deactivates the time domain windowing Time domain windowing is a method to influence the spectral characteristics of the sig nal which is not stipulated by the standard However it does not replace oversampling and subsequent signal filtering Remote command SOURce lt hw gt BB WLAN TDWindowing STATe on page 60 Transition Time Sets the transition time when time domain windowing is active MAC Header and FCS Configuration The transition time defines the overlap range of two OFDM symbols At a setting of 100 ns one sample overlaps Remote command SOURce lt hw gt BB WLAN TTIMe on page 61 Configure MAC Header and FCS Calls the menu for configuration of the MAC Header and FSC The menu is described in chapter 3 3 MAC Header and FCS Configuration on page 34 Remote command n a 3 3 MAC Header and FCS Configuration In the real IEEE 802 11 system a MAC medium access control header is transmitted in the PSDU prior to the actual data section This header comprises control information of the MAC layer It is also possible to protect the PSDU by a frame checksum These two functions can be controlled in the menu SS IEEE B02 11g WLAN A MAC Header and FCS Configuration MAC Header Off Address 2 hex Address 3 hex Enable Enable foooo 0000 0000 FCS checksum Activates deactivates the calculation of the FCS frame check sequ
21. the idle time refers to the chip rate as defined in the standard 11 Mcps for 802 11b g CCK PBCC and 20 Mops for 802 11a g OFDM Only at this chip rate does the idle period correspond exactly to the time set If the chip rate is doubled for instance the real idle time is halved Remote command SOURce lt hw gt BB WLAN ITIMe on page 53 PPDU Configuration This feature is available for Framed Mode only Calls the menu for configuration of the PPDU The menu differs for the physical layer modes The menu is described in chapter 3 2 PPDU Sequence Configuration on page 27 Remote command n a Sequence Configuration This feature is available for Unframed Mode only Calls the menu for configuration of the signal in unframed mode modes The menu is described in chapter 3 2 PPDU Sequence Configuration on page 27 Remote command n a Filter Clipping Calls the menu for setting the filter parameters and the clipping The current setting is displayed next to the button The menu is described in section chapter 3 5 Filter Clipping Settings on page 38 Remote command n a Trigger Marker Calls the menu for selecting the trigger source for configuring the marker signals and for setting the time delay of an external trigger signal see chapter 3 6 Trigger Marker Clock Settings on page 40 The currently selected trigger source is displayed to the right of the button Remote command n a
22. the current IEE 802 11a g WLAN settings into the selected file The directory is set using command MMEM CDIRectory A path can also be specified in which case the files in the specified directory are read Only the file name has to be entered IEE 802 11a g WLAN settings are stored as files with the specific file exten sions wlan Setting parameters Filename string Example BB WLAN SETT STOR wlan g stores the current settings into file wlan o Usage Setting only Manual operation See Save Recall on page 23 General Commands SOURce lt hw gt BB WLAN SETTing STORe FAST Fast Determines whether the instrument performs an absolute or a differential storing of the settings Enable this function to accelerate the saving process by saving only the settings with values different to the default ones Note This function is not affected by the Preset function Parameters Fast 0 1 OFF ON RST 1 SOURce hw BB WLAN SLENgth lt Slength gt The command selects the number of frames The command is only valid in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Slength gt float Range 1 to depends on other settings RST 1 Example BB WLAN SLEN 4 selects the generation of 4 frames Manual operation See Sequence Length on page 25 SOURce lt hw gt BB WLAN SMODe lt Smode gt The command selects the simulation mode Parameters lt Smode gt FRAMed U
23. the data of the preamble is scrambled RST OFDM RANDom CCK PBCC ON Example BB WLAN SCR OFF the scrambler is deactivated General Commands Manual operation See Scrambler on page 32 SOURce lt hw gt BB WLAN SCRambler PATTern Pattern The command enters the initialization value for scrambling mode User This value is then identical in each generated frame The command is only available for physical layer mode OFDM SOURce BB WLAN MODE OFDM Parameters Pattern integer Range H0 0 to HFF 8 RST HO 0 Example BB WLAN SCR USER the scrambler is activated BB WLAN SCR PATT H3F 8 the initialization value is set Manual operation See Scrambler Init hex OFDM on page 33 SOURce lt hw gt BB WLAN SERVice PATTern lt Pattern gt The command enters the value for service field The command is only available for physical layer mode OFDM SOURce BB WLAN MODE OFDM Parameters lt Pattern gt integer Range H0 0 to HFF 8 RST H0 0 Example BB WLAN SERV PATT H3F 8 the value for the service field is set Manual operation See Service field hex on page 33 SOURce lt hw gt BB WLAN SETTing CATalog Reads out the files with IEEE 802 11a g settings in the default directory The default directory is set using command MMEM CDIRectory Only files with the file extension wlan Will be listed Return values Catalog string Example MMEM
24. upper menu section is where the IEEE 802 11a g WLAN digital standard is enabled and the basic signal structure is configured State Activates the standard and deactivates all the other digital standards and digital modu lation modes in the same path Remote command SOURce lt hw gt BB WLAN STATe on page 60 Set to default Calls the default settings The values of the main parameters are listed in the following table Parameter Value State Not affected by Set to default Standard 802 11g Physical Layer Mode CCK Simulation Mode Framed Predefined Frames Data Sequence Length 1 frame Idle Time 0 1 ms Filter Gauss FSK 0 50 Chip Rate Variation 11 Mcps Clipping Off PPDU Configuration CCK PLCP P H Format Long PLPC PSDU Bit Rate CCK PBCC 11 Mbps Data Length 1024 bytes PSDU Data Source PRBS 9 Scrambling On Service Field Clock Bits Locked MAC Header Off FCS checksum Off Remote command SOURce lt hw gt BB WLAN PRESet on page 56 General Settings for WLAN Signals Save Recall Calls the Save Recall menu From the Save Recall menu the File Select windows for saving and recalling IEEE 802 11a g WLAN configurations and the File Manager can be called IEEE 802 11a g WLAN configurations are stored as files with the predefined file exten sion wlan The file name and the directory they are stored in are user definable
25. 2 11b Manual operation See Standard on page 23 SOURce lt hw gt BB WLAN STATe State Activates the standard and deactivates all the other digital standards and digital modu lation modes in the same path Parameters State 0 1 OFF ON RST 0 Example SOURCel BB WLAN STATe ON Manual operation See State on page 22 SOURce lt hw gt BB WLAN TDWindowing STATe State The command activates deactivates the time domain windowing Time domain win dowing is a method to influence the spectral characteristics of the signal which is not stipulated by the standard However it does not replace oversampling and subsequent signal filtering The command is only available for physical layer mode OFDM SOURce BB WLAN MODE OFDM 4 2 Filter Clipping Settings Parameters State 0 1 OFF ON RST OFF Example BB WLAN TDW STAT OFF deactivates the time domain windowing Manual operation See Time Domain Windowing Active on page 33 SOURce lt hw gt BB WLAN TTIMe lt Ttime gt The command sets the transition time The transition time defines the overlap range of two OFDM symbols when time domain windowing is active At a setting of 100 ns one sample overlaps This command is only available in physical layer mode OFDM SOURce BB WLAN MODE OFDM and with active time domain windowing SOURce BB WLAN TDWindowing STATe ON Parameters lt Ttime gt float Range 0 to 1000 ns Increme
26. 990 IEEE founded the work group 802 11 which issued a first version of the 802 11 standard in June 1997 This standard defines two transmission methods an infrared interface and radio transmission in the ISM band around 2 4 GHz Radio transmission can alternatively be carried out via frequency hopping spread spec trum FHSS or direct sequence spread spectrum DSSS Originally two data transmission modes were defined for the DSSS method e 1 Mbps data rate with DBPSK modulation e 2Mbps data rate with DOPSK modulation Both modes spread the information data sequence with an 11 chip Barker sequence and operate with a chip rate of 11 Mcps In spring 1999 the standard was extended by an OFDM mode 802 11a in the 5 GHz band Soon afterwards in summer 1999 the DSSS mode was extended too This expansion to include the new data rates of 5 5 Mbps and 11 Mbps is defined in the 802 11b standard A new modulation mode complementary code keying CCK was introduced see following sections Standard 802 11g issued in 2003 extends standard 802 11b with higher transmission rates It includes the previous 802 11b standard and implements the OFDM transmis sion of standard 802 11a in the 2 4 GHz ISM band In the physical layer the packet structure and modulation format of the OFDM modes are identical in 802 11g and 802 11a only different transmission frequencies are used The 802 11 wireless LAN standard is a packet oriented method for data tran
27. AN Signals eese 22 3 2 PPDU Sequence Configuration eeseeeeeeseeeseseeeeeene ener ennt nnns 27 3 2 1 Standard 802 11a OFDM etie tete iden et SER E Ea 27 3 2 2 Standard 802 11b g CCK DR 28 SA QUIN OS EEUU 29 3 3 MAC Header and FCS Configuration c cccccscccesseeeeeseeeeeneeeeeeneeeseeeeeseneeesseeeeeeeness 34 SA dcpsmeeem 37 3 5 Filter Clipping Settings cccccccsseeeescceesseeeeeeeeeeeneeeeeeneeeseaeeeeneeeseeaeseseeeeessaeeesneeeeeeas 38 3 5 Filter e E 38 3 5 2 Clipping Settings on Fri rere ete ED d eiie lax Forge eL ade era da ea e dA E 39 3 6 Trigger Marker Clock Settings sseeeeeeesssseeeeeeeeeeeeneen nnne nnns 40 S01 EGO EE 41 36 2 Marker MO r 46 3 0 2 Marker Delay reete tectae tite d entrare ONENA EEE 47 Kee e E 47 3 6 5 Global Settings uei er def nee era Ced kde Mas HR ER VE e S RO Rad 49 4 Remote Control Commands cessere 51 DN Ce lu E DE 52 4 Filter Clipping E d CN 61 4 3 Trigger Settings nre irren tioni xnc exin nra Enn x RR AREE Rana 66 44 Eed E 72 4 5 Clock Setting E 77 BR EI E 79 E e E fet c 89 i T P 91 1 1 Documentation Overview Preface Documentation Overview The user documentation for the R amp S Signal Generator consists of the following parts e Online
28. CDIR root wlan sets the default directory BB WLAN SETT CAT reads out all the files with IEEE 802 11a g settings in the default directory Response wlana wlang the files w1ana and wlang are available General Commands Usage Query only Manual operation See Save Recall on page 23 SOURce lt hw gt BB WLAN SETTing DELete Filename This command deletes the selected file with IEEE 802 11a g WLAN settings The directory is set using command MMEM CDIRectory A path can also be specified in which case the files in the specified directory are read The file extension may be omit ted Only files with the file extension w1an will be deleted Parameters Filename string Example BB WLAN SETT DEL wlana deletes file wlana Manual operation See Save Recall on page 23 SOURce lt hw gt BB WLAN SETTing LOAD Filename This command loads the selected file with IEEE 802 11a g WLAN settings The direc tory is set using command MMEM CDIRectory A path can also be specified in which case the files in the specified directory are read The file extension may be omitted Only files with the file extension w1an will be loaded Setting parameters Filename string Example BB WLAN SETT LOAD wlana loads file wlana Usage Setting only Manual operation See Save Recall on page 23 SOURce lt hw gt BB WLAN SETTing STORe Filename This command stores
29. Clock Settings The Marker Mode section is where the marker signals at the MARKER output con nectors are configured Marker Marker 1 Pattern Marker 2 On Off Ratio Y Marker 3 Pattern Marker 4 Pattern The Marker Delay section is where a marker signal delay can be defined either with out restriction or restricted to the dynamic section i e the section in which it is possi ble to make settings without restarting signal and marker generation Marker Delay Current Range Without Recalculation 2000 Samples 0 2000 Samples 2000 Samples S CECEl ELELKLLECEEeIL ODAAiQ 0 000 Samples m debe Dee dg Oo Don TB gap o TE De m 0 2000 Samples Fix Marker Delay To Current Range I The Clock Settings section is where the clock source is selected and in the case of an external source the clock type Settings Clock Source Internat The buttons in the last section lead to submenu for general trigger clock and mapping settings Global TriggeriClock Settings User Marker AUX I O Settings 3 6 1 Trigger In The Trigger In section is where the trigger for the signal is set Various parameters will be provided for the settings depending on which trigger source internal or exter nal is selected The current status of signal generation Running or Stopped is indicated for all trigger modes Trigger Marker Clock Settings Trigger Mode Selects trigger mode i e determines
30. E PATTern 0 is marker off 1 is marker on Parameters lt Pattern gt 32 bit pattern RST B 1 Example BB WLAN TRIG OUTP2 PATT B000000011111111 15 sets a bit pattern BB WLAN TRIG OUTP2 MODE PATT activates the marker signal according to a bit pattern on output MARKER 2 Manual operation See Marker Mode on page 46 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt PULSe DIVider lt Divider gt The command sets the divider for Pulse marker mode SOUR BB WLAN TRIG OUTP MODE PULSe The resulting pulse frequency is derived by dividing the symbol rate by the divider Parameters lt Divider gt float Range 2 to 1024 Increment 1 RST 2 Example BB WLAN TRIG OUTP2 PULS DIV 2 sets the divider to 2 for the marker signal on output MARKER 2 BB WLAN TRIG OUTP2 FREQ queries the resulting pulse frequency of the marker signal Response 66 000 the resulting pulse frequency is 66 kHz Manual operation See Marker Mode on page 46 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt PULSe FREQuency The command queries the pulse frequency of the pulsed marker signal in the setting SOURce BB WLAN TRIGger OUTPut MODE PULSe The pulse frequency is derived by dividing the symbol rate by the divider Return values lt Frequency gt float Clock Settings Example BB WLAN TRIG OUTP2 PULS DIV 2 sets the divider marker signal on output MARKER 2 to the value 2
31. EESEN 56 TSOUbRcechwzslBBWL AN SGChamblerMODE eene nennen enne nnns 56 SOURce hw BB WLAN SCRambler PATTern sss nennen enn 57 SOURce hw BB WLAN SERVice PATTern eniieeeeeeee siena nnn tnn nn ntis nnn 57 SOURce lt hw gt BB WLAN SET Ting CATalog ui liii coire ec tede k cese u s Eb arcos naa Rice 57 ESOURce shw T BB WLEAN SET Ting DELete 2 tonto tut hehe tenuit nonet ne catania 58 ESOURcCeshw I BBWEANISETTIngEORND iicet euet cepa tert eth rete 58 ESOURcexhw EBB WLEAN SETTing S TORe 2 riesce cce tL oec eth ERKENNEN 58 SOURceshiw E BB WLAN SET Ting S TORG EAST entren perra nn n x nante a aaa EE 59 SOURce hw BB WLAN SLENgfh eeeceeeetn ttt tette tenente ettet ttt 59 SOURGe hw rBBAVEANISMOPDSA EE 59 ESOURceshw EBBIWEAN STAN datd 2 titia idees creciente nen tae vk av edu 60 Be e EE BB WLAN RN KEN 60 ESOURGe hw EBB WEAN TDWindowirig S TA Te eege dna tna eene tad 60 SOURceshw EBBANWEANETTIMa 2 oret corona et epar ER tu o nne rh ee cedente ne aS ERR cR 61 SOURce hw BB WLAN WAVeform CREate sisse nennen 61 General Commands SOURce lt hw gt BB WLAN FFORmat lt Fformat gt The command selects the frame type The selection defines parameters of the MAC layer e g the values of the MAC Header bit fields The command is only valid in framed mode SOURce BB WLAN SMODe FRAMed The selection defines parameters of the
32. Execute Trigger This feature is available for Trigger Source Internal only Executes trigger manually A manual trigger can be executed only when an internal trigger source and a trigger mode other than Auto have been selected Remote command SOURce lt hw gt BB WLAN TRIGger EXECute on page 67 PPDU Sequence Configuration Clock Calls the menu for selecting the clock source see chapter 3 6 Trigger Marker Clock Settings on page 40 Remote command n a 3 2 PPDU Sequence Configuration In framed mode a frame consists of a PPDU PLCP protocol data unit and the idle time The data packet on the physical layer is referred to as PPDU A PPDU consists of three components the PLCP preamble the PLCP header and the PSDU PLCP ser vice data unit which contains the actual information data coming from higher layers The PLCP preamble and header are used for synchronization and signaling purposes and are themselves divided into fields The details of the PPDU structure depend on the selected standard or more precisely on the physical layer mode see below In unframed mode the signal can be configured via the PSDU bit rate and PSDU modulation parameters just as in the Framed mode However a preamble or header is not generated only a continuous PSDU block is generated the length of which can be varied by using the Sequence Length parameter There is no restriction of the maximum PSDU block length to 4095 b
33. FlXed Fixed for R amp S SMx AMU instrumenets only The command restricts the marker delay setting range to the dynamic range In this range the delay can be set without restarting the marker and signal If a delay is entered in setting ON but is outside this range the maximum possible delay is set and an error message is generated Parameters lt Fixed gt 0 1 OFF ON RST OFF Example BB WLAN TRIG OUTP DEL FIX ON restricts the marker signal delay setting range to the dynamic range Manual operation See Fix marker delay to current range on page 47 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt DELay Delay for R amp S SMx AMU instrumenets only The command defines the delay between the signal on the marker outputs and the start of the signal expressed in terms of chips Com mand BB WLAN TRIGger OUTPut DELay FIXed can be used to restrict the range of values to the dynamic range i e the range within which a delay of the marker sig nals can be set without restarting the marker and signal Parameters lt Delay gt float Range O to 2432 1 chips Increment 1 chip RST 0 Example BB WLAN TRIG OUTP2 DEL 1600 sets a delay of 1600 chips for the signal on connector MARKER 2 Manual operation See Marker x Delay on page 47 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt DELay MAXimum for R amp S SMx AMU instrumenets only Marker Settings The command querie
34. Help system on the instrument e Quick Start Guide printed manual e Documentation CD ROM with Online help system chm as a standalone help Operating Manuals for base unit and options Service Manual Data sheet and specifications Links to useful sites on the R amp S internet 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 The online help contains help on operating the R amp S Signal Generator and all available options Quick Start Guide The Quick Start Guide is delivered with the instrument in printed form and in PDF for mat on the Documentation CD ROM It provides the information needed to set up and start working with the instrument Basic operations and an example of setup are descri bed The manual includes also general information e g Safety Instructions Operating Manuals The Operating Manuals are a supplement to the Quick Start Guide Operating Manuals are provided for the base unit and each additional software option These manuals are available in PDF format in printable form on the Documentation CD ROM delivered with the instrument In the Operating Manual for the base unit all instrument functions are described in detail Furthermore it provides an introduction to remote control and a complete description of the remote control commands with pro gra
35. IEEE 802 11 a b g Digital Standard for R amp S9Signal Generators Operating Manual III 1171 5283 12 15 E 2 5 E E o D o Ee o o This document describes the following software options R amp S9SMBV K48 1415 8102 xx R amp S SMU K48 1161 0266 02 R amp S AMU K48 1402 6706 02 R amp S SMATE K48 1404 6703 02 R amp S SMJ K48 1404 1001 02 This manual version corresponds to firmware version FW 3 20 281 xx and later of the R amp S SMBV100A FW 2 20 360 142 and later of the R amp S SMU200A R amp S SMATE200A R amp S9SMJ100A and R amp S AMU200A 2015 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 Email 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 manual R amp S AMU200A is abbreviated as R amp S AMU R amp S9SMATE200A is abbreviated as R amp S SMATE R amp S9SMBV100A is abbreviated as R amp S SMBV R amp S SMJ100A is abbreviated as R amp S SMJ R amp S SMU200A is abbreviated as R amp S SMU R amp S WinIQSIM2 is abbreviated as R amp S WinlQSIMZ2 the license types 02 03 07 11 13 16 12 are abbreviated as xx Contents
36. ILTer PARameter RCOSine sse 65 TSOUbRcechuwslBBWL AN Fi TerbAameter Gase 65 SOURce hw BB WLAN CRATe VARiation esses nennen nennen nnne 66 Dm ms 3 SOURce hw BB WLAN CLIPping LEVel Level The command sets the limit for level clipping This value indicates at what point the sig nal is clipped It is specified as a percentage relative to the highest level 100 indi cates that clipping does not take place Level clipping is activated with the command SOUR BB WLAN CLIP STAT ON Parameters Level float Range 1 to 100 RST 100 Default unit PCT Example BB WLAN CLIP LEV 80PCT sets the limit for level clipping to 8096 of the maximum level BB WLAN CLIP STAT ON activates level clipping Manual operation See Clipping Level on page 40 SOURce lt hw gt BB WLAN CLIPping MODE Mode The command sets the method for level clipping Clipping Parameters lt Mode gt VECTor SCALar VECTor The reference level is the amplitude i jq SCALar The reference level is the absolute maximum of the and Q val ues RST VECTor Example Manual operation Filter Clipping Settings BB WLAN CLIP MODE SCAL selects the absolute maximum of all the and Q values as the reference level BB WLAN CLIP LEV 80PCT sets the limit for level clipping
37. LAN PSDU MAC FCONItrol MDATa eee 84 SOURce shw BB WLAN PSDU MAC FCONtrol MFRagments eere 84 SOURce hw BB WLAN PSDU MAC FCONtrol ORDer eene 84 SOURce hw BB WLAN PSDU MAC FCONtrol PMANagement eene 84 SOURce hw BB WLAN PSDU MAC FCONItrol PVERSion eene 84 SOURce hw BB WLAN PSDU MAC FCONItrol RETRY eee 84 SOURce hw BB WLAN PSDU MAC FCONtrol SUBType eee 84 SOURcCeshw5EBBAWEAN PSDUIMAC ECONIrOET DS zio uoo oit eee ee rore cueste eege 84 SOURce lt hw gt BB WLAN PSDU MAC FCONHrol TYPE sirrinin iinan 84 SOURce hw BB WLAN PSDU MAC FCONtrol WEP eese nennen 84 SOURce lt hw gt BB WLAN PSDU MAC FC ZeouenceGfAie E 85 SOURce hw BB WLAN PSDU MAC SCONtrol FRAGment INCRement 85 SOURce hw BB WLAN PSDU MAC SCONtrol FRAGment STARt eese 85 SOURce shw BB WLAN PSDU MAC SCONtrol SEQuence INCRement 86 SOURce hw BB WLAN PSDU MAC SCONtrol SEQuence STARt eese 86 SOURce shw BB WLAN PSDU MAC SCONItrol STATe esee een 86 TGOUlbcechbwslBB WLANPGDUIMACSTATe nennen nennt 87 ESOURGe hw ErBBAVEANIPSDUMODUlatlOnI 222 cote eoo rta ote ttti 87 ESOURce hw EBBWEAN PSDUESQCOXUhtL 22 2 22 or accion deese cot eite ed oaa dee 87 SOURce lt hw gt BB
38. LCB STAT OFF disables the Locked Clock Bit Manual operation See Service Field Clock Bit CCK PBCC on page 33 SOURce hw BB WLAN PRESet The command produces a standardized default for the IEEE 802 11a g standard The settings correspond to the RST values specified for the commands Example BB WLAN PRES resets all the IEEE 802 11a g settings to default values Usage Event Manual operation See Set to default on page 22 SOURce lt hw gt BB WLAN SCRambler MODE Mode The command activates deactivates the scrambler and selects the mode of determin ing the initialization value The valid parameters depend on the selected physical layer mode SOURce BB WLAN MODE OFDM CCK PBCC Parameters Mode OFF ON PONLy RANDom USER OFF The scrambler is deactivated RANDom OFDM only The scrambler is activated The initialization value of the scrambler is selected at random Each frame has a differ ent random initialization value This value is also different in case of successive recalculations with the same setting parame ters so that different signals are generated for each calculation USER OFDM only The scrambler is activated The initialization value of the scrambler is set to a fixed value that is entered at Scram bler Init hex This value is then identical in each generated frame ON CCK PBCC only The scrambler is activated PONLy CCK PBCC only The scrambler is activated Only
39. MAC layer e g the values of the MAC Header bit fields Parameters Fformat DATA RTS CTS ACK USER DATA Predefined settings for data transmission RTS Predefined settings for Request to Send CTS Predefined settings for Clear to Send ACK Predefined settings for Acknowledgement USER User defined settings response for query only RST DATA Example BB WLAN SMODe FRAM selects framed mode BB WLAN FFOR RTS selects frame type RTS Manual operation See Predefined Frames on page 25 SOURce lt hw gt BB WLAN ILEaver STATe State The command activates deactivates the interleaver This command is only available in physical layer mode OFDM SOURce BB WLAN MODE OFDM Parameters State 0 1 OFF ON RST ON Example BB WLAN STAN STAN80211g selects standard 802 119 BB WLAN MODE OFDM selects physical layer mode OFDM BB WLAN ILE ON activates the interleaver Manual operation See Interleaver Active OFDM on page 33 SOURce lt hw gt BB WLAN ITIMe ITime The command selects the Physical Layer Mode General Commands Parameters lt ITime gt float OFDM The OFDM orthogonal frequency division multiplexing physical layer supports a frame based transmission The OFDM orthog onal frequency division multiplexing signal is divided into 52 carriers The symbol rate of the modulation on the individual car riers is 250 kHz A user data rate of up t
40. Mbps rates In contrast to the 5 5 Mbps und 11 Mbps PBCC modes a rate 2 3 convolutional coder and 8PSK modulation are used With 33 Mbps also the clock rate in the data section of the packet is increased to 16 5 Mcps Data Spreading and Modulation CCK PBCC 3 WLAN User Interface TDMA standards The menu for setting the IEEE 802 11a g WLAN digital standard is either called from GSMEDGE senge the baseband block or from the menu tree under Baseband cuc The menu is split into several sections for configuring the standard The choice of sim OFDMWLAN standards ulation mode determines which displays and parameters are made available in the IEEE 802 11 WLAN ti IEEE 802 16 WiMAX ower secuon The upper section of the menu is where the IEEE 802 11a g WLAN digital standard is enabled the default settings are called and the physical layer mode the simulation mode and the frame type are selected Additional parameters for defining the signal length and a graph outlining the signal structure are indicated A button leads to the submenu for loading and saving the IEEE 802 11a g WLAN con figuration IEEE 802 11g WLAN A D Su To eta Generate Waveform File 802 119 The buttons of the lower menu section lead to submenus for configuring the PPDU and for setting the filter clipping and marker parameters Trigger Marker Execute Trigger General Settings for WLAN Signals 3 1 General Settings for WLAN Signals The
41. NFRamed FRAMed The framed mode is the standard operating mode which is also used in the real system Data packets with the frame structure defined by the standard are generated UNFRamed The unframed mode is offered in addition In this mode a non packet oriented signal without a frame structure is generated with the modulations and data rates defined by 802 11a g RST FRAMed Example BB WLAN SMOD UNFR selects unframed mode Manual operation See Simulation Mode on page 24 General Commands SOURce lt hw gt BB WLAN STANdard Standard The command selects the standard according to which the signal is simulated Parameters Standard STAN80211A STAN80211B STAN80211G STAN80211A The standard supports OFDM orthogonal frequency division multiplexing This modulation is defined by the IEEE 802 11a specification in the 5 GHz frequency band STAN80211B The standard includes the modulation mode CCK complemen tary code keying and the data rates 5 5 Mbps and 11 Mbps PBCC packet binary convolutional coding can optionally be used instead of CCK modulation for the 5 5 Mbps and 11 Mbps data rates STAN80211G Standard 802 11g extends standard 802 11b with higher trans mission rates 802 119 contains the previous 802 11b modes and also integrates the OFDM method used in 802 11a for fre quencies in the 2 4 GHz band RST STAN80211G Example BB WLAN STAN STAN80211B selects signal generation according to 80
42. OURce lt hw gt BB WLAN WAVeform CREate on page 61 Standard Selects the 802 11 standard The standard was expanded over the years adding additional features 802 112 The standard supports OFDM orthogonal frequency division multi plexing This modulation is defined by the IEEE 802 112 specifica tion in the 5 GHz frequency band 802 11b 802 119 General Settings for WLAN Signals The standard includes the modulation mode CCK complementary code keying and the data rates 5 5 Mbps and 11 Mbps PBCC packet binary convolutional coding can optionally be used instead of CCK modulation for the 5 5 Mbps and 11 Mbps data rates Standard 802 11g extends standard 802 11b with higher transmission rates 802 11g contains the previous 802 11b modes and also inte grates the OFDM method used in 802 11a for frequencies in the 2 4 GHz band Remote command SOURce lt hw gt BR WLAN STANdard on page 60 Physical Layer Mode Selects the physical layer mode OFDM CCK PBCC The OFDM orthogonal frequency division multiplexing physical layer supports a frame based transmission The OFDM signal is divided into 52 carriers The symbol rate of the modulation on the individual carriers is 250 kHz A user data rate of up to 54 Mbps at a channel bandwidth of 20 MHz can be obtained by combining 48 useful carri ers for data transmission 4 carriers are used for pilots and using 64QAM for subcarrier modulation Wi
43. OURce lt hw gt BB WLAN PSDU MAC SCONtrol SEQuence INCRement SOURce hw BB WLAN PSDU MAC SCONItrol SEQuence STARt essen SOURce hw BB WLAN PSDU MAC SCONItrOoI STATe essent rennen nnne SOURC shw EBB WEAN PSDU MAGC S TATO rica oce bnt ra Pa ee FU e EH Ee ele RE WLAN PSDU RTE RE 87 Ree ER EIER Rer TEE SOURce lt hw gt BB WLAN SCRambler MODE si SOURceshw BB WLAN SGRambler PAT Tetris ntm ng ett te petu np eee an kh cop ta an 57 SOURce lt hw gt BB WLAN SERVicel PAT Tenn 24 tt certet ert ere t tec 57 SOURcC sliw BB WEAN SETTing CATaloQ ico error trece ae i yet re enr ER eg 57 SOURce hw BB WLAN SETTing DELete eese eee netten enne trennen Ree ER EUR aper RE SOURce lt hw gt BB WLAN SETTING S TORG EE SOURce lt hw gt BB WLAN SETTing STORe FAST E SOURcCeshws IER Gr e UE SOURCeshwS EBBIWEAN SMODBDJA ao eter Eege Bie cot t EE re Den cians Re RE UR E D SOURCeshw EBB WEAN ISTATO att cti trece io n Dette ane SOURceshw BB WEAN TDWindowing STATe 1 aa ea erect tar rece ees SOURce hw BB WLAN TRIGger ARM EXE CuUte eeeeeee neither nett ttn tata ta NAS TE ROEE NCSE Sisa 66 SOURce lt hw gt BB WLAN TRIGger EXE Ule 2 ctt tette pp rece dte d dede repo 67 SOURce hw BB WLAN TRIGger EXTernal SYNChronize OUTPut essen 67 SOURce hw BB WLAN TRIGger OBASeband DELay
44. Range H000000000000 48 to HFFFFFFFFFFFF 48 RST H000000000000 48 Example BB WLAN PSDU MAC ADDR2 H124836C7EA54 48 set the value for address field 2 Manual operation See MAC Address on page 35 SOURce lt hw gt BB WLAN PSDU MAC ADDRess lt ch gt STATe lt State gt The command activates deactivates the selected address field The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt State gt 0 1 OFF ON RST OFF Example BB WLAN PSDU MAC ADDR2 STAT ON activates generation of address field 2 SOURce lt hw gt BB WLAN PSDU MAC DID Did The command enters the value of the duration Id field Depending on the frame type the 2 byte field Duration ID is used to transmit the association identity of the station transmitting the frame or it indicates the duration assigned to the frame type Exactly 16 bit must be entered The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Did gt integer Range H0000 16 to HFFFF 16 RST HO0000 16 Example BB WLAN PSDU MAC FORM HA5A5 16 sets the value of the duration Id field Manual operation See Duration Id on page 35 IEEE 802 11 a b g Remote Control Commands pc M PP r H en SOURce lt hw gt BB WLAN PSDU MAC FCONtrol lt FControl gt The command enters the value of the frame
45. SDU MAC SCON SEQ STAR H4 4 sets the start value of the sequence bits of the sequence control Manual operation See Sequence Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol STATe State The command activates deactivates the sequence control The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt State gt 0 1 OFF ON RST OFF PSDU Settings Example BB WLAN PSDU MAC SCON STAT ON activates the sequence control field Manual operation See Sequence Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC STATe State The command activates deactivates the generation of the MAC Header The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMedQ Parameters State 0 1 OFF ON RST OFF Example BB WLAN PSDU MAC SCON STAT ON activates the generation of the MAC Header Manual operation See MAC Header on page 34 SOURce lt hw gt BB WLAN PSDU MODulation The command queries the modulation type The modulation mode depends on the selected PSDU bit rate which depends on the selected physical layer mode SOURce BB WLAN MODE Return values lt Modulation gt BPSK QPSK QAM16 QAM64 DBPSk DQPSk CCK PBCC Example BB WLAN PSDU MOD queries the modulation mode Response DQPSK Usage Query only Manual operation See PSDU Modulation on page 30 SOURc
46. The input is made in terms of chips It is possible to output deliberately just part of the frame an exact sequence of the frame or a defined number of repetitions of the frame Parameters lt SLength gt float Range 1 to 2432 1 chips Increment 1 chip RST 32 768 chips Trigger Settings Example BB WLAN SEQ SING sets trigger mode Single BB WLAN TRIG SLEN 200 sets a sequence length of 200 chips The first 200 chips of the current frame will be output after the next trigger event Manual operation See Signal Duration on page 42 SOURce lt hw gt BB WLAN TRIGger SLUNit lt Slunit gt The command defines the unit for the entry of the length of the signal sequence SOUR BB WLAN TRIG SLEN to be output in the Single trigger mode SOUR BB WLAN SEQ SING Parameters lt Slunit gt FRAMe CHIP SEQuence FRAMe Unit Frame A single frame is generated after a trigger event CHIP Unit Chip A single chip is generated after a trigger event SEQuence Unit Sequence Length A single sequence is generated after a trigger event RST SEQuence Example BB WLAN SEQ SING sets trigger mode Single BB WLAN TRIG SLUN FRAM sets unit Frame for the entry of sequence length BB WLAN TRIG SLEN 2 sets a sequence length of 2 frame Two frames will be output after the next trigger event Manual operation See Signal Duration on page 42 SOURce l
47. WLAN PSDU BRATe lt Brate gt The command selects the bit rate of the PSDU The available values depend on the selected physical layer mode Value 1MBPS is available only for selection of long PLCP format in physical layer modes CCK and PBCC Parameters lt Brate gt 6MBPS 9MBPS 12MBPS 18MBPS 24MBPS 36MBPS 48MBPS 54MBPS RST OFDM 54MBPS CCK PBCC 11MBPS Example BB WLAN MODE selects physical layer mode OFDM BB WLAN PSDU BRAT 12MBPS sets a bit rate of 12MBPS Manual operation See PSDU Bit Rate on page 30 SOURce lt hw gt BB WLAN PSDU BSPReading STATe State The command activates deactivates barker spreading The command is only available only for selection of bit rates 1MBPS or 2 MBPS in physical layer modes CCK and PBCC PSDU Settings Parameters State 0 1 OFF ON RST ON Example BB WLAN MODE CCK selects physical layer mode CCK BB WLAN PSDU PLCP FORM LONG selects long PLCP format BB WLAN PSDU BRAT 1MBPS sets a bit rate of 1MBPS BB WLAN PSDU BSPR OFF deactivates barker spreading SOURce lt hw gt BB WLAN PSDU DATA Data The command determines the data source for the data field Parameters Data PN9 PN15 PN16 PN20 PN21 PN23 DLISt ZERO ONE PATTern PNxx The pseudo random sequence generator is used as the data source Different random sequence lengths can be selected DLISt A d
48. a rate of 11 Mbps The modulation is basically the same as described for the 5 5 Mbps data rate In each modulation step eight successive bits dO to d7 are taken from the data stream which is already scrambled The phases 2 03 are determined by these eight bits Q4 is determined by the data bits d0 and d1 according to the following table which specifies different phases for even and odd modulation steps Dibit pattern do d d is first in Even symbols phase change Odd symbols phase change time 00 0 pi 01 pi 2 3pi 2 pi 2 11 pi 0 10 3pi 2 pi 2 pi 2 The phase must be interpreted relative to the phase of the previous symbol Q is determined by the data bits d d3 4 from d4 ds and qs from de d according to the following table Dibit pattern d d do is first in time Phase change 00 0 01 pi 2 11 pi 10 3pi 2 pi 2 Data Spreading and Modulation CCK PBCC 2 3 5 5 5 Mbps and 11 Mbps Data Rates with PBCC Modulation Packet binary convolutional coding PBCC can optionally be used instead of CCK modulation for the 5 5 Mbps and 11 Mbps data rates The following illustration provides a schematic overview of this method For details refer to the standard Fig 2 2 Principle of PBCC modulation 2 3 6 22 Mbps and 33 Mbps Data Rates with PBCC Modulation 802 11g also defines the optional PBCC ER PBCC modes using the extended 22 Mbps and 33
49. a user defined value OFDM Clipping for reducing the crest factor To playback a signal from a waveform file created by the simulation software R amp S WinlQSIM2 the corresponding R amp S WinlQSIM2 digital standard option must be installed 2 1 Physical Layer OFDM The standard defines OFDM orthogonal frequency division multiplex with 52 carriers as transmission method The symbol rate of the modulation on the individual carriers is 250 kHz A user data rate of up to 54 Mbps at a channel bandwidth of 20 MHz can be obtained by combining 48 useful carriers for data transmission 4 carriers are used for pilots and using 64QAM for subcarrier modulation With OFDM the individual carriers are superimposed mutually orthogonal which in the ideal case does not cause any intercarrier interference ICI Table 2 1 Parameters of 802 11a g OFDM modulation Parameters Value Number of data subcarriers 48 Number of pilot subcarriers 4 Total of subcarriers used 52 Subcarrier frequency spacing 0 3125 MHz 20 MHz 64 IFFT FFT period 3 2 us Guard interval duration 0 8 us TFFT 4 Symbol interval 4 us TGI TFFT PLCP preamble duration 16 us Subcarrier modulation BPSK OFDM QPSK OFDM 16QAM OFDM 64QAM OFDM Error correction code K 7 64 states convolutional code Code rates 1 2 2 3 3 4 2 1 1 Physical Layer OFDM Parameters Value Occupied bandwidth 16
50. age 84 AN PSDU MAC FCONtro1 FDS on page 84 PSDU MAC FCONtrol1 MFRagments on page 84 N PSDU MAC FCONtrol RETRy on page 84 N PSDU MAC FCONtrol PMANagement on page 84 PSDU MAC FCONtrol MDATa on page 84 N PSDU MAC FCONtrol WEP on page 84 N PSDU MAC FCONtrol ORDer on page 84 1 D m d C db B SOURce lt hw gt SOURce lt hw gt SOURce lt hw gt SOURce lt hw gt zou uw oS pe ee Se Se se 5 TA UJ P tJ tU QU UJ UJ UJ UJ Duration Id Enters the value of the duration Id field Depending on the frame type the 2 byte field Duration ID is used to transmit the asso ciation identity of the station transmitting the frame or it indicates the duration assigned to the frame type Remote command SOURce lt hw gt BB WLAN PSDU MAC DID on page 83 MAC Address Enters the value of the address fields 1 4 The MAC header may contain up to four address fields but not all of them must be available Each of the 4 address fields can be activated or deactivated The fields are used for transmitting the basic service set identifier the destination address the Source address the receiver address and the transmitter address Each address is 6 bytes 48 bit long The addresses can be entered in hexadecimal form in the entry field of each address field The least significant byte LSB is in left notation Remote command SOURce
51. ameters lt Wep gt lt Fds gt lt Mdata gt lt Mfragments gt lt Order gt lt Pmanagement gt lt Pversion gt lt Retry gt lt TDS gt Range HO 1 to H1 1 RST HO 1 lt Subtype gt integer Range H0 4 to HF 4 RST HO 1 lt Type gt integer Range HO0 2 to H3 2 RST HO 1 Example BB WLAN PSDU MAC FCON WEP H1 1 sets the value of the More Data bit Operating Manual 1171 5283 12 15 84 PSDU Settings Manual operation See Frame Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC FCSequence STATe State Activates deactivates the calculation of the FCS frame check sequence The stand ard defines a 32 bit 4 byte check sum to protect the MAC header and the user data frame body The command is only available in framed mode SOURce BB WLAN SMODe FRAMed Parameters State 0 1 OFF ON Range H0000 16 to HFFFF 16 RST OFF Example BB WLAN PSDU MAC FCS STAT ON activates the calculation of the FCS Manual operation See FCS checksum on page 34 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol FRAGment INCRement lt Increment gt Defines the number of packets required to increment the counter of the fragment bits of the sequence control The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Increment gt float Range 0 to 1024 RST 1 Example BB WLAN PSDU MAC SCON FRAG INCR 2 two packets are required to increment
52. ands are required to perform signal generation with the IEEE 802 11a g WLAN option in a remote environment We assume that the R amp S Signal Generator has already been set up for remote operation in a network as described in the R amp S Signal Generator documentation A knowledge about the remote control oper ation and the SCPI command syntax are assumed o Conventions used in SCPI command descriptions For a description of the conventions used in the remote command descriptions see section Remote Control Commands in the R amp S Signal Generator operating manual Common Suffixes The following common suffixes are used in remote commands Placeholder root Suffix Value range Description SOURce lt hw gt DI available baseband signals OUTPut ch 1 4 available markers R amp S SMBV supports two markers EXTernal lt ch gt 1 2 external trigger connectors For commands that read out or save files in the default directory the default directory is set using command MMi EM CDIRectory The examples in this description use the place holder root in the syntax of the command e D N for selecting the internal hard disk of a Windows instrument E for selecting the memory stick which is inserted at the USB interface of a Windows instrument e var user for selecting the internal flash card of a Linux instrument e usb for selecting the memory stick which is inserted at the USB interface o
53. ata list is used The data list is selected with the command SOURce lt hw gt BB WLAN PSDU DATA DSELect ZERO ONE Internal O and 1 data is used PATTern Internal data is used The bit pattern for the data is defined by the command SOURce hw BB WLAN PSDU DATA PATTern RST PN9 Example BB WLAN PSDU DATA PATT selects as the data source for the data fields of burst 0 the bit pattern defined with the following command BB WLAN PSDU DATA PATT H3F 8 defines the bit pattern Manual operation See PSDU Data Sorce on page 31 SOURce lt hw gt BB WLAN PSDU DATA DSELect lt DSelect gt The command selects the data list for the DLISt data source selection The lists are stored as files with the fixed file extensions dm_igqd in a directory of the user s choice The directory applicable to the following commands is defined with the command MMEMory CDIR To access the files in this directory you only have to give the file name without the path and the file extension PSDU Settings Parameters lt DSelect gt string Example BB WLAN PSDU DATA DLIS selects the Data Lists data source MMEM CDIR lt root gt Lists selects the directory for the data lists BB WLAN PSDU MAC DATA DLIS wlan listl selects file wlan_list1 as the data source Manual operation See PSDU Data Sorce on page 31 SOURce lt hw gt BB WLAN PSDU DATA PATTern Pattern The command determines the bit patte
54. crambled i e multiplied with a PN sequence A 127 bit code generated by the follow ing generator polynomial is stipulated S x x x44 A feedback shift register generates the scrambling sequence The start value of the register for the data section should be randomly selected A subsequent convolutional coder adds redundancies to the bits thus scrambled factor of 2 The coder has 64 possible states k 7 and is described by the polynomials Qo 133g and g4 171 To obtain the data rates of 6 to 54 Mbps defined by the stand ard different channel code rates are required Bits generated by the convolutional coder are therefore punctured i e omitted depending on the setting so that 1 2 2 3 or 3 4 code rates are attained Increasing the redundancy by channel coding is generally mandatory in case of OFDM modulations since complete subcarriers may be elimina ted by frequency selective fading so that the loss of bits on the transmission path is in many cases unavoidable To increase the performance of the convolutional coder the coded data are interleaved in the next step Two interleaver stages ensure that the adjacent bits of the convolu tional coder are first distributed to different subcarriers and then to higher or lower sig nificant bits of the constellation used for subcarrier modulation Long sequences of defective bits can thus be avoided which significantly improves the faculties of the Viterbi decoder in the receiver for a co
55. cts clock type Chip i e the supplied clock is a chip clock Manual operation See Clock Mode on page 48 SOURce lt hw gt BB WLAN CLOCk MULTiplier lt Multiplier gt The command specifies the multiplier for clock type Multiplied BB WLAN CLOCk MODE MCHip in the case of an external clock source Clock Settings For two path instruments the only numerical suffix allowed for SOURce is 1 since the external clock source is permanently allocated to path A Parameters lt Multiplier gt float Range 1 Increment 1 RST 4 Example BB WLAN CLOC SOUR EXT selects the external clock source The clock is supplied via the CLOCK connector BB WLAN CLOC MODE MCH selects clock type Multiplied i e the supplied clock has a rate which is a multiple of the chip rate BB WLAN CLOC MULT 12 the multiplier for the external clock rate is 12 to 64 Manual operation See Chip Clock Multiplier on page 48 SOURce hw BB WLAN CLOCKk SOURce Source The command selects the clock source For two path instruments selecting EXTernal is only possible for path A since the external clock source is permanently allocated to path A selecting AINTernal is only possible for path B Parameters Source INTernal EXTernal AINTernal INTernal The internal clock reference is used EXTernal The external clock reference is supplied to the CLOCK connec tor RST INTernal Exa
56. data source for the data field The following standard data sources are available e All O All 1 An internally generated sequence containing 0 data or 1 data e PNxx An internally generated pseudo random noise sequence Pattern An internally generated sequence according to a bit pattern Use the Pattern box to define the bit pattern e Data List Select DList A binary data from a data list internally or externally generated Select Select DList to access the standard Select List dialog Select the Select Data List gt navigate to the list file dm_iqd gt Select to select an existing data list Use the New and Edit functions to create internally new data list or to edit an existing one Use the standard File Manager function to transfer external data lists to the instrument See also Main Dialog gt Data List Management Remote command SOURce hw BB SOURce hw BB SOURce hw BB zi AN PSDU DATA on page 81 AN PSDU DATA PATTern on page 82 AN PSDU DATA DSELect on page 81 zi zi PPDU Sequence Configuration Data List Management Calls the Data List Management menu This menu is used to create and edit a data list EC Data List Management Edit Data List None All data lists are stored as files with the predefined file extension dm_igqd The file name and the directory they are stored in are user definable
57. e EVM however increases Since clipping the signal not only changes the peak value but also the aver age value the effect on the crest factor is unpredictable Remote command SOURce lt hw gt BB WLAN CLIPping STATe on page 63 Clipping Level Sets the limit for clipping This value indicates at what point the signal is clipped It is specified as a percentage relative to the highest level 100 indicates that clipping does not take place Remote command SOURce lt hw gt BB WLAN CLIPping LEVel on page 62 Clipping Mode Selects the clipping method A graphic illustration of the way in which these two meth ods work is given in the menu Vector i q The limit is related to the amplitude i q The and Q components are mapped together the angle is retained Scalar i The limit is related to the absolute maximum of all the and Q values qr i Iql The and Q components are mapped separately the angle changes Remote command SOURce hw BB WLAN CLIPping MODE on page 62 3 6 Trigger Marker Clock Settings To access this dialog select Main Menu gt Trigger Marker The Trigger In section is where the trigger for the signal is set Various parameters will be provided for the settings depending on which trigger source internal or exter nal is selected The current status of signal generation Running or Stopped is indicated for all trigger modes Trigger Marker
58. e R amp S Signal Generator product page at the Down loads Web Help area Application Notes Application notes application cards white papers and educational notes are further publications that provide more comprehensive descriptions and background informa tion The latest versions are available for download from the Rohde amp Schwarz website at http www rohde schwarz com appnotes 1 2 Conventions Used in the Documentation 1 2 1 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 ments dialog boxes menus options buttons and softkeys are enclosed by quotation marks KEYS Key names are written in capital letters 1 2 2 1 2 3 Conventions Used in the Documentation Convention Description File names commands File names 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 quota tion marks Notes on Screenshots When describing the functions of the product we use sample screenshots These screenshots are meant to illustrate as much as possible of the provided functions a
59. e instrument provides all connected instrument with its syn chronization including the trigger signal and reference clock signal SLAVe The instrument receives the synchronization and reference clock signal from another instrument working in a master mode RST NONE Example BB WLAN CLOC SYNC MODE MAST the instrument is configured to work as a master one Manual operation See Sync Mode on page 47 PSDU Settings The SOURce BB WLAN PSDU system contains commands for setting the characteris tics of the data packet on the physical layer PPDU SOURceshw pEBBWEAN PSDUFESBRATe 1 7 irit e dva ENEE EESRERN E suu 2a bac pone pa NeEeEn 80 SOURce hw BB WLAN PSDU BSPReading STATe sse 80 SOURce lt hw gt BB WLAN PSDU DATA 0 ccccceeeeee cece ee aandui inaina nnii anar iaai snnt 81 SOURGe hw BBIAWEANIPSDU DATA DSELel rior tete eae nt ente va 81 PSDU Settings SOURce hw BB WLAN PSDU DATA PAT Tern ie cezse editi senes nhan eaae tena aa 82 ESOURce hw EBBWEAN PSDU DEE Net 2 3 c tait ex en tu tas et nene epu ene a 82 SOURce hw BB WLAN PSDU MAC ADDRess Ch sess 83 LSOUbRcechwz DBB WL AN PSDU MAC AUDDbess chzGTATe 83 SOURCeshwsE BBSWEANIPSDUFIMAGC BID 2 5 2 60 9 312 rote E ee soto pope ep N Raa 83 TSOUbRcechwzslBBWL AN PGDU MAC FCOhol nennen enne 84 SOURce hw BB WLAN PSDU MAC FCONtrol FDS eee 84 SOURce shw BB W
60. e lt hw gt BB WLAN PSDU SCOunt lt Scount gt The command sets the number of data symbols If the number of OFDM data symbols is changed the generator calculates the data field length as a function of the set PSDU bit rate The command is only available in physical layer mode OFDM SOURce BB WLAN MODE OFDM If the number of OFDM data symbols is changed the generator calculates the data field length SOUR BB WLAN PSDU DLEN as a function of the set PSDU bit rate PSDU Settings Parameters Scount float Range 1 to 1378 RST 4 Example BB WLAN PSDU SCO 256 sets the number of data symbols to 256 Manual operation See Number of Data Symbols OFDM on page 31 List of Commands SOURceshw BB WLAN CLIPpirg EEVel rtt thee ttm tiere mr ere teneri NEEN 62 SOURcCeshw T BB WLAN GLIPping dl RTE 62 SOURceshw BB WLAN GUIPping STA Te eot rtt reet rennen 63 SOURceshw 2 BB WLAN CLOGCICMOBBE 2 itt roten eni rr err ao ehe ke reet tere rrr gene 77 ele RE CR er eer RI 77 SOURce lt hw gt BB WLAN CLOCk SOURce SOURce hw BB WLAN CLOCK SYNChronization EXECute sese 78 SOURce hw BB WLAN CLOCKk SYNChronization MODE essent 79 SOURceshw5 BB WLAN CRATe VAR iation tioni entere tn re rir SE DENEN YENi 66 SOURceshw BB WLAN EFOR tIBL 1 rernm rr ertet at nn thang re Yita endete orina eap 53 SOURce hw BB WLAN
61. e scrambler is activated PPDU Sequence Configuration Preamble The scrambler is activated Only Only the preamble is scrambled Remote command SOURce lt hw gt BB WLAN SCRambler MODE on page 56 Service Field Clock Bit CCK PBCC Sets the Locked Clock Bit in Service Field of the PLCP Header Via this flag bit the 802 11b g transmitter indicates whether transmission frequency and symbol rate have been derived from the same oscillator If this is the case locked the bit is set to 1 otherwise not locked to 0 Remote command SOURce lt hw gt BB WLAN PLCP LCBit STATe on page 55 Disable Barker Spreading CCK PBCC Activates deactivates barker spreading bit rates 1 Mbps or 2 Mbps only Remote command SOURce lt hw gt BB WLAN PLCP LCBit STATe on page 55 Scrambler Init hex OFDM Enters the initialization value for scrambling mode User This value is then identical in each generated frame Remote command SOURce lt hw gt BB WLAN SCRambler PATTern on page 57 Interleaver Active OFDM Activates deactivates the interleaver Remote command SOURce lt hw gt BB WLAN ILEaver STATe on page 53 Service field hex Enters the value of the service field The standard specifies a default value of 0 Other values can be entered in hexadecimal form for test purposes or future extensions Remote command SOURce lt hw gt BB WLAN SERVice PATTern
62. ence The stand ard defines a 32 bit 4 byte check sum to protect the MAC header and the user data frame body Remote command SOURce lt hw gt BB WLAN PSDU MAC FCSequence STATe on page 85 MAC Header Activates deactivates the generation of the MAC Header for the PSDU If the MAC header is activated all MAC header fields are enabled for operation The individual fields of the MAC header are described in the following MAC Header and FCS Configuration All values of the MAC fields except addresses are entered in hexadecimal form with LSB in right notation In the data stream the values are output standard conformal with the LSB coming first Remote command SOURce hw BB WLAN PSDU MAC STATe on page 87 Frame Control Enters the value of the frame control field The Frame control field has a length of 2 bytes 16 bits and is used to define the pro tocol version the frame type sub type and its function etc As an alternative the indi vidual bits can be set in the lower part of the graph Remote command SOURCe nhw BB SOURCe hw BB SOURce lt hw gt BB SOURce lt hw gt B SOURce lt hw gt B SOURce lt hw gt B SOURce lt hw gt B SOURce lt hw gt B B B B B LAN PSDU MAC FCONtrol on page 84 LAN PSDU MAC FCONtrol PVERsion on page 84 LAN PSDU MAC FCONtrol TYPE on page 84 AN PSDU MAC FCONtrol SUBType on page 84 AN PSDU MAC FCONt ro1 TDS on p
63. er tenen trn ede un 61 SOURce lt hw gt BB WLAN TRIGger SEQuence Index A Addresses osos aepo HER EC Ca o PR taney 35 PATNI oscuras xe eX nens 43 Arm Trigger WLAN 66 Armed Auto A Armed Retrigger zi foo n 71 B pda per M 63 Baseband filt r 5 iet es 38 63 Jg P 39 C CCK mode 24 53 54 Chip COCK ccd rrr oerte aiis erronea 48 Chip Clock Multiplier 48 77 Chip Rate Variation terr rtr ren 39 Clipping Level coenae rre 40 62 Clipping Mode 40 62 Clock Mode 48 77 Clock il 27 CloCK eru 48 78 Conventions SCPI COMMANAS rrr ete Crest factor Clipping Crest factor Clipping S Current Range without Recalculation 47 73 Cut Off Frequency Factor nter 39 D Data Length Data List Management Data pattern Dera lt e E Delay MARK GN eegener m Delay LrIggel eege eret cote recente Delete IEEE 802 11a g WLAN settings Disable Barker Spreading CCK PBCC Documentation overview Duration Id en cdeawecievdconesanenacsoiesentesncaaevanesnieweedeescans E Le e ECK ER 32 Execute Trlgger rsrsrsr eaan 26 43 67 External Trigger Delay cone en orte roe Aae 71 External Trigger InblbiE counties eorura cernere 71 F io
64. f a Linux instrument General Commands 4 1 Tasks in manual or remote operation that are also performed in the base unit in the same way are not described here In particular this includes e Managing settings and data lists i e storing and loading settings creating and accessing data lists accessing files in a particular directory etc e Information on regular trigger marker and clock signals as well as filter settings if appropriate General instrument configuration such as configuring networks and remote opera tion Using the common status registers For a description of such tasks see the R amp S Signal Generator operating manual The following commands specific to the SOURce BB WLAN subsystem are described here Gensral Comm E 52 e Filter Clipping Settings A 61 Tigger SetiNgS UE UU 66 e Makar SOUINGS n E O ERR a dec aigdacdaed ideas 72 Clock Sewing s EE 77 e FoDU SAOS eon retenti oce e cr nd O 79 General Commands ESOURce shw TBBIWEANIBEPORDSL EE 53 LSOUbRcechwzslBBWL ANIL aver GTAaTe eene nennen nnns nennt nnns 53 Ree ER EC H MR ET 53 SOURceshw EBBANEAN MODE iiiiiier oso ty ccudidtas ccce oua aca cde d cei deos aee ed Sana un 54 ESOURce shw EBBIWWEAN PEOPJIPORMAal 2222 o roe xenon Fou etg E Rv ce in ener ne tnde 55 ESOURGeshw BBAVEAN PEOPAECBIUSTAT ttr tert oett aeta he attt ne 55 SOURceshw EBBANEAN PRESel erii scott rari eir eed na ad R
65. g 39 63 Stopped ett o nre en rit ee 42 Sync Output to External Trigger siirinsesi 43 Synchronization mode nette nens 47 Synchronization Mode entrer dresses 79 T Time Domain Windowing Active OFDM 33 60 Transition Time n Trigger Delay adessias eia renes Trigger Delay External erret Trigger Delay Other Baseband Trigger Inbibit terr terr mr ete Trigger Inhibit External retten Trigger Inhibit Other Baseband 68 Trigger Mode ees re al Armed 42 PU WT 42 Retrigger 42 Ie ea eai a arepita 42 Trigger paraimelers edm the terrier 26 Migger SOUE eite nere redes 43 U User Marker AUX I O Settings ssssss 49 Ww Waveform RIGA sicuti e eris Cla ton exte o RA 23
66. hich is identical for all transmission methods Moreover this protocol informs the receiver on the type of signal sent to allow for a correct demodulation The PLCP generates the PLCP protocol data unit PPDU frames which are physically transmitted PLCP Preamble Each frame starts with the PLCP preamble made up of 10 short and 2 long symbols The receiver uses the short symbols mainly for signal detection AGC coarse fre quency adjustment and time synchronization The long symbols are used to determine the transmission function of the channel and to set the equalizer of the receiver accord Physical Layer OFDM ingly The complete preamble is 16 us long and thus corresponds to the duration of 4 normal OFDM symbols Signal Field The signal field directly follows the preamble and consists of 24 bits which are used as follows RATE LENGTH SIGNAL TAIL 4 bits 12 bits 6 bits Transmit Order The first 4 bits inform on the data rate RATE of the following data section This allows the receiver to correctly set its demodulator Following a reserved bit 12 LENGTH bits are sent They contain the number of bytes transmitted in this frame After a parity bit 6 tail bits reset the convolutional coder to zero With settings for 6 Mbps the 24 bits are subjected to usual signal processing consist ing of convolutional coding interleaving BPSK subcarrier modulation pilot carrier gen eration and OFDM modulation and thus form exact
67. ield contains a check sum of all the fields of the PLCP header The PLCP preamble and the PLCP header in the long PLCP PPDU format are both DBPSK modulated and transmitted at a data rate of 1 Mbps The data rate and the modulation of the PSDU component are defined by the signal and service fields in the PLCP header The frame structure can be seen in the figure below also indicated in the PPDU Con figuration dialog Short PLCP PPDU Format The basic structure of the short PLCP PPDU format is identical to that of the long PLCP PPDU format There is no difference in the PSDU component The PLCP pre amble and header are generated in an abbreviated form In the short preamble the 2 3 Data Spreading and Modulation CCK PBCC number of bits transmitted in the SYNC field is reduced from 128 to 56 In the short header however the number of data bits transmitted remains unchanged but the data rate is doubled to 2 Mbps These measures halve the transmission periods of pream ble and header in the short PLCP format as compared to the long PLCP format The frame structure can be seen in the figure below also indicated in the PPDU Con figuration dialog Data Spreading and Modulation CCK PBCC The R amp S Signal Generator simulates signals in accordance with 802 11 on the physi cal layer In the standard the data link layer or to be more precise the MAC sublayer provides the input data for this layer The following graph illustrate
68. igger Marker Clock Settings Sync Master The instrument provides all connected instrument with its synchroni sation including the trigger signal and reference clock signal lock Settings Sync Mode Sync Master Set Synchronisation Settings Sync Slave The instrument receives the synchronisation and reference clock sig nal from another instrument working in a master mode Remote command SOURce hw BB WLAN CLOCk SYNChronization MODE on page 79 Set Synchronization Settings for R amp S SMBV only Performs automatically adjustment of the instrument s settings required for the syn chronization mode selected with the parameter Synchronization Mode Remote command SOURce lt hw gt BB WLAN CLOCk SYNChronization EXECute on page 78 Clock Source Selects the clock source Internal The internal clock reference is used to generate the symbol clock External The external clock reference is fed in as the symbol clock or multiple thereof via the CLOCK connector The symbol rate must be correctly set to an accuracy of 2 see data sheet The polarity of the clock input can be changed with the aid of Global Trigger Clock Settings In the case of two path instruments this selection applies to path A Remote command SOURce lt hw gt BB WLAN CLOCk SOURce on page 78 Clock Mode Clock source External only Enters the type of externally supplied clock Chip A chip clock is supplied
69. instrument s processing time the first samples are cut off and no signal is outputted After elapsing of the internal processing time the output signal is syn chronous to the trigger event OFF The signal output begins after elapsing of the processing time and starts with sample 0 i e the complete signal is outputted This mode is recommended for triggering of short signal sequen ces with signal duration comparable with the processing time of the instrument RST ON BB WLAN TRIG SOUR EXT sets external triggering BB WLAN TRIG EXT SYNC OUTP ON enables synchrounous output to external trigger See Sync Output to External Trigger on page 43 SOURce hw BB WLAN TRIGger OBASeband DELay Delay The command specifies the trigger delay expressed as a number of chips for trigger ing by the trigger signal from the second path Parameters Delay Example float Range O chips to 2432 1 chips Increment 1 chip RST 0 chips BB WLAN TRIG SOUR OBAS sets for path A the internal trigger executed by the trigger signal from the second path path B BB WLAN TRIG OBAS DEL 50 sets a delay of 50 chips for the trigger SOURce lt hw gt BB WLAN TRIGger OBASeband INHibit lt Inhibit gt The command specifies the number of chips by which a restart is to be inhibited follow ing a trigger event This command applies only for triggering by the second path Parameters lt I
70. is range the delay of the marker signals can be set without restarting the marker and signal Remote command SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt DELay on page 73 Current Range without Recalculation Displays the dynamic range within which the delay of the marker signals can be set without restarting the marker and signal The delay can be defined by moving the setting mark Remote command SOURce lt hw gt BB WLAN TRIGger OUTPut ch DELay MINimum on page 74 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt DELay MAXimum on page 73 Fix marker delay to current range Restricts the marker delay setting range to the dynamic range In this range the delay can be set without restarting the marker and signal Remote command SOURce lt hw gt BB WLAN TRIGger OUTPut DELay FI Xed on page 73 Clock Settings The Clock Settings is used to set the clock source and a delay if required Sync Mode for R amp S SMBV only Selects the synchronization mode This parameter is used to enable generation of very precise synchronous signal of sev eral connected R amp S SMBVs Note If several instruments are connected the connecting cables from the master instrument to the slave one and between each two consecutive slave instruments must have the same length and type Avoid unnecessary cable length and branching points None The instrument is working in stand alone mode Tr
71. ker signal is generated at the start of each signal sequence period selected number of frames FRAMe A marker signal is generated at the start of each frame period PPDU idle time FACTive A marker signal is generated at the start of every active part of the frame PATTern A marker signal is generated according to the user defined pat tern PULSe A pulsed marker signal is generated RATio A ON OFF marker signal is generated TRIGger A received internal or external trigger signal is output at the marker connector RST RESTart Example BB WLAN TRIG OUTP2 MODE FRAM selects the frame marker signal on output MARKER 2 Manual operation See Marker Mode on page 46 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt ONTime lt OnTime gt SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt OFFTime lt OffTfime gt The command sets the number of chips in a period ON time OFF time during which the marker signal in setting SOURce BB WLAN TRIGger OUTPut MODE RATio on the marker outputs is OFF Parameters OffTime float Range 1 to 16777215 Increment 1 RST 1 Example BB WLAN TRIG OUTP2 OFFT 200 sets an OFF time of 200 chips for marker signal 2 Manual operation See Marker Mode on page 46 Marker Settings SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt PATTern Pattern The command defines the bit pattern used to generate the marker signal in the setting SOURce BB WLAN TRIGger OUTPut MOD
72. l processing time the output signal is synchronous to the trigger event Ext Trigger Event Calculated signal Signal at the output Trigger Marker Clock Settings Off The signal output begins after elapsing of the processing time and starts with sample 0 i e the complete signal is outputted This mode is recommended for triggering of short signal sequences with signal duration comparable with the processing time of the instrument Ext Trigger Event Calculated signal Signal at the output Remote command SOURce lt hw gt BB WLAN TRIGger EXTernal SYNChronize OUTPut on page 67 Trigger Delay Delays the trigger event of the signal from e the external trigger source the other path Use this setting to e synchronize the instrument with the device under test DUT or other external devi ces Remote command SOURCce hw BB SOURce hw BB zi AN TRIGger EXTernal ch DELay on page 71 AN TRIGger OBASeband INHibit on page 68 zi Trigger Inhibit Sets the duration for inhibiting a new trigger event subsequent to triggering The input is to be expressed in samples In the Retrigger mode every trigger signal causes signal generation to restart This restart is inhibited for the specified number of samples This parameter is only available on external triggering or on internal triggering via the second path For two path instruments
73. lt hw gt BB WLAN PSDU MAC ADDRess ch on page 83 Sequence Control Activates deactivates the sequence control field MAC Header and FCS Configuration The sequence control field has a length of 2 bytes and is divided in two parts the frag ment number 4 bits and the sequence number 12 bits field A long user data stream to be transmitted is first split up into MSDUs MAC service data units which can either be transmitted as PSDU frames or further divided into fragments The sequence num ber and the fragment number are then used to number the individual subpackets of the user data stream to be transmitted Thus all PSDUs are assigned a consecutive num ber This allows the receiver to arrange the data packets in the correct order to deter mine whether an incorrectly transmitted packet was retransmitted and to find out whether packets are missing If the receiver can detect a packet without an error and does not request a retransmis sion the sequence number is incremented by 1 for each packet the field is reset to 0 at the latest after a count of 4095 The fragment number field is incremented by 1 when another fragment of the current MPDU is transmitted The start count for the transmission normally 0 and the number of packets required to increment the corre sponding counter can be defined for both numbers This is done with the parameters Start Number and Incremented every packet s see below Example An e
74. ly one OFDM symbol of 4 us dura tion Thanks to the use of the lowest data rate 6 Mbps each receiver has the best chance to obtain the information required for subsequent demodulation of the data sec tion User Data The user data in the data section of the frame is finally taken to the receiver The data section may have a variable length of OFDM symbols and can be transmitted with one of the defined data rates between 6 and 54 Mbps The data section of the frame is sub divided into the fields SERVICE PSDU TAIL and Pad bits SERVICE PSDU TAIL Pad 16 Bits 6 Bits Bits The service field consists of 16 bits the 7 LSBs transmitted first being O The allows the receiver to draw conclusions as to the start value of the scrambler in the transmit ter The remaining 9 bits are reserved and according to the current version of the standard should also be set to 0 The PSDU may have a user selectable length of up to 2346 bytes 6 tail bits follow to reset the convolutional coder to zero The data field must be filled with the full number of OFDM symbols and is therefore rounded up Additional bits that may be available are set to 0 as pad bits A short description of the individual steps required to attain a valid 802 11a g signal fol lows IEEE 802 11 a b g Introduction rM J H n Data from the source usually the next higher protocol layer here MAC must first be s
75. mming examples Information on maintenance instrument interfaces and error messages is also given In the individual option manuals the specific functions of the option 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 Signal Generator is not included in the option manuals Conventions Used in the Documentation Service Manual The Service Manual is available in PDF format in printable form on the Documenta tion CD ROM delivered with the instrument It describes how to check compliance with rated specifications on instrument function repair troubleshooting and fault elimina tion It contains all information required for repairing the instrument by the replacement of modules This manual can also be orderd in printed form see ordering information in the data sheet Release Notes The release notes describe 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 current release notes are provided in the Internet Web Help The web help provides online access to the complete information on operating the R amp S Signal Generator and all available options without downloading The content of the web help corresponds to the user manuals for the latest product version The web help is available on th
76. mple BB WLAN CLOC SOUR EXT selects an external clock reference The clock is supplied via the CLOCK connector BB WLAN CLOC MODE CHIP specifies that a chip clock is supplied via the CLOCK connector Manual operation See Clock Source on page 48 SOURce lt hw gt BB WLAN CLOCk SYNChronization EXECute for R amp S SMBV only Performs automatically adjustment of the instrument s settings required for the syn chronization mode set with the command SOURce lt hw gt BB WLAN CLOCk SYNChronization MODE 4 6 PSDU Settings Example BB WLAN CLOC SYNC MODE MAST the instrument is configured to work as a master one BB WLAN CLOC SYNC EXEC all synchronization s settings are adjusted accordingly Usage Event Manual operation See Set Synchronization Settings on page 48 SOURce lt hw gt BB WLAN CLOCk SYNChronization MODE Mode for R amp S SMBV only Selects the synchronization mode This parameter is used to enable generation of very precise synchronous signal of sev eral connected R amp S SMBVs Note If several instruments are connected the connecting cables from the master instrument to the slave one and between each two consecutive slave instruments must have the same length and type Avoid unnecessary cable length and branching points Parameters Mode NONE MASTer SLAVe NONE The instrument is working in stand alone mode MASTer Th
77. nce STARt on page 86 Increment Every Defines the number of packets required to increment the counter of the fragment bits or the sequence bits of the sequence control Remote command SOURce lt hw gt BB WLAN PSDU MAC SCONtrol FRAGment INCRement on page 85 SOURce hw BB WLAN PSDU MAC SCONtrol SEQuence INCRement on page 86 Frame Body Indicates the length of the user data frame body Remote command n a FCS Indicates the length of the check sum Remote command n a 3 4 PPDU Graph The frame graph in the lower part of the menu indicates the configuration of the PPDU The frame structure for the different physical layer modes is described in chapter 2 2 Physical Layer CCK PBCC on page 14 PLCP Header Coded OFDM Coded OFDM BPSK r 1 2 Rate is indicated in Signal Fig 3 1 Physical layer Mode OFDM Filter Clipping Settings Fig 3 2 Physical layer Mode CCK Long PLCP 3 5 Filter Clipping Settings To access this dialog select Main Menu gt Filter Clipping The baseband filter sample rate variation and clipping are defined in this menu E5 IEEE 802 11 WLAN A Filter Settings Filter Gauss FSK BT Chip Rate Variation 11 000 000 Mcps D State On Clipping Level 100 Clipping Mode Vector li j l z 3 5 1 Filter Settings Filter Sets the baseband filter This opens a selection window containing all the fil
78. nd possible interdependencies between parameters The shown values may not represent realistic test situations The screenshots usually show a fully equipped product that is with all options instal led Thus some functions shown in the screenshots may not be available in your par ticular product configuration Naming of Software Options In this operating manual we explicitly refer to options required for specific functions of the digital standard The name of software options for signal generators vary in the name of the instrument but the option name is identical Therefore we use in this manual the placeholder R amp S SMx AMU Example Naming for an option of the vector signal generator R amp S SMBV100A e g e R amp S SMx AMU K98 stands for R amp S SMBV K99 The particular software options available for the corresponding instruments are listed on the back of the title page Conventions Used in the Documentation IEEE 802 11 a b g Introduction 2 Introduction The R amp S Signal Generator provides you with the ability to generate signals in accord ance with the Wireless LAN standards IEEE 802 11a IEEE 802 11b and IEEE 802 11g IEEE 802 11 standard WLAN IEEE 802 11 stands for a wireless LAN standard prepared by ANSI IEEE Institute of Electrical and Electronics Engineers A brief description of the standard is given in the following For a detailed description see the corresponding ANSI IEEE specifications In 1
79. nhibit gt float Range O to 2432 1 chips Increment 1 chip RST 0 chips Trigger Settings Example BB WLAN TRIG SOUR OBAS sets for path A the internal trigger executed by the trigger signal from the second path path B BB WLAN TRIG INH 200 sets a restart inhibit for 200 chips following a trigger event Manual operation See Trigger Delay on page 45 SOURce lt hw gt BB WLAN TRIGger RMODe The command queries the current status of signal generation for all trigger modes with IEEE 802 11a g WLAN modulation on Return values lt RMode gt STOP RUN RUN the signal is generated A trigger event occurred in the triggered mode STOP the signal is not generated A trigger event did not occur in the triggered modes or signal generation was stopped by the com mand BB WLAN TRIG ARM EXECute armed trigger modes only Example BB WLAN TRIG SOUR EXT sets external triggering via the TRIGGER 1 connector BB WLAN TRIG MODE ARET selects the Armed_Retrigger mode BB WLAN TRIG RMOD queries the current status of signal generation Response RUN the signal is generated an external trigger was executed Usage Query only Manual operation See Running Stopped on page 42 SOURce lt hw gt BB WLAN TRIGger SLENgth lt SLength gt The command defines the length of the signal sequence to be output in the Single trigger mode SOUR BB WLAN SEQ SING
80. nt 1ns RST 100 ns Example BB WLAN TTIM 10 ns sets a transition time of 10 ns Manual operation See Transition Time on page 33 SOURce lt hw gt BB WLAN WAVeform CREate Filename Creates a waveform using the current settings of the WLAN dialog The file name is entered with the command The file is stored with the predefined file extension wv The file name and the directory it is stored in are user definable Setting parameters Filename string Example MMEM CDIR root waveform sets the default directory BB WLAN WAV CRE wlan creates the waveform file w1an wv in the default directory Usage Setting only Manual operation See Generate Waveform File on page 23 Filter Clipping Settings SOURceshw EBB WLAN CLIPping lEVel 2222 2 arceat reed iara na caca 62 ESOURce hw E BB WLAN CLIPping MODPB einen tenu pente Rage ecu aaa EE REE 62 TSOUbRcechwzslBBWL AN CLlPping STATe neret enne nns 63 Filter Clipping Settings ESOURce lt hw gt BB WLAN FILTEN TYPE morania aaar te re rx oe a eu eo 63 LSOUbRcechwzslBBWL AN Fil TerbAameier AbCO3p nnne 63 SOURce hw BB WLAN FILTer PARameter COSine essere 64 SOURce lt hw gt BB WLAN FILTer PARameter GAUSS nnne 64 SOURce lt hw gt BB WLAN FILTer PARameter LPASS eene 64 TSOUbRcechwzslBBWL AN Fi TerbAameier DAGGEVNM nemen 65 TSOUbRcechuwslBBWL AN Fi TerbAameterbGAuss eene 65 SOURce hw BB WLAN F
81. o 54 Mbps at a channel bandwidth of 20 MHz can be obtained by combining 48 useful carriers for data transmission 4 carriers are used for pilots and using 64QAM for subcarrier modulation With OFDM the individ ual carriers are superimposed mutually orthogonal which in the ideal case does not cause any intercarrier interference ICI CCK The CCK complementary code keying physical layer mode is used for the 5 5 Mbps and 11 Mbps data rates PBCC The PBCC packet binary convolutional coding physical layer can optionally be used instead of CCK modulation Range 0 to 1 RST OFDM Example BB WLAN MODE OFDM selects physical layer mode OFDM Manual operation See Idle time on page 25 SOURce lt hw gt BB WLAN MODE Mode The command selects the Physical Layer Mode Parameters Mode Example Manual operation General Commands CCK PBCC OFDM OFDM The OFDM orthogonal frequency division multiplexing physical layer supports a frame based transmission The OFDM orthog onal frequency division multiplexing signal is divided into 52 carriers The symbol rate of the modulation on the individual car riers is 250 kHz A user data rate of up to 54 Mbps at a channel bandwidth of 20 MHz can be obtained by combining 48 useful carriers for data transmission 4 carriers are used for pilots and using 64QAM for subcarrier modulation With OFDM the individ ual carriers are superimposed mutually orthogonal
82. odulation mode depends on the selected PSDU bit rate PSDU Modu Indicates the modulation type The modulation mode depends on the lation selected PSDU bit rate The Physical Layer Mode parameter in the CCK PBCC main menu can be used for switchover between CCK and PBCC Remote command SOURce lt hw gt BB WLAN PSDU MODulation on page 87 PPDU Sequence Configuration Data Length Sets the data length In the framed mode data field lengths of up to 4095 bytes per frame packet are possi ble This corresponds to the maximum data length If the MAC Layer is activated the MAC header up to 30 and the 4 FCS bytes are added The unframed mode offers a data length of up to 100000 bytes OFDM If the data field length is changed the generator calculates the number of OFDM data symbols as a function of the set PSDU bit rate and displays it in the field Number of Data Symbols Data is always rounded up to complete symbols Free data bits in the last symbol the so called pad bits are filled with O Remote command SOURce lt hw gt BB WLAN PSDU DLENgth on page 82 Number of Data Symbols OFDM Sets the number of data symbols per frame packet If the number of OFDM data symbols is changed the generator calculates the data field length as a function of the set PSDU bit rate and displays it at Data Length Remote command SOURce lt hw gt BB WLAN PSDU SCOunt on page 87 PSDU Data Sorce Selects the
83. page 76 SOURce hw BB WLAN TRIGger OUTPut ch PULSe FREQuency on page 76 Pattern A marker signal that is defined by a bit pattern is generated The pat tern has a maximum length of 64 bits and is defined in an input field which opens when pattern is selected Remote command SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt PATTern on page 76 ON OFF A regular marker signal that is defined by an ON OFF ratio is gener Period ated A period lasts one ON and OFF cycle The ON Time and OFF Time are each expressed as a number of samples and are set in an input field which opens when ON OFF ratio is selected ON time OFF time ON time OFF time Remote command SOURce lt hw gt BB SOURce lt hw gt BB AN TRIGger OUTPut lt ch gt ONTime on page 75 AN TRIGger OUTPut lt ch gt OFFTime on page 75 Remote command SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt MODE on page 74 3 6 3 3 6 4 Trigger Marker Clock Settings Marker Delay The delay of the signals on the MARKER outputs is set in the Marker Delay section The R amp S SMBV supports only two markers Marker x Delay Enters the delay between the marker signal at the marker outputs and the start of the frame or slot The input is expressed as a number of symbols samples If the setting Fix marker delay to dynamic range is enabled the setting range is restricted to the dynamic range In th
84. parameters of the data part PSDU are set In framed mode a distinction is made between the packet type or PPDU format with long or short PLCP physical layer convergence protocol A graph in the lower sec tions illustrates the structure of the PPDU framed mode or the unframed sequence unframed mode e Framed Mode PPDU Sequence Configuration amp IEEE 802 11g CCK WLAN A PPDU Configuration PSDU Bit Rate CCK PBCC 11 Mbps v PSDU Modulation CCK DQPSK Data Length 1024 bytes v PSDU Data Source PRBS9 z Data List Management Scrambling On R Service Field Clock Bits Locked m Configure MAC Header and FCS e Unframed Mode E5 IEEE 802 11g PBCC WLAN Sequence Configuration PSDU Bit Rate CCK PBCC 11 Mbps v PSDU Modulation PBCC QPSK Data Length 1021 bytes PSDU Data Source PRBS9 z Data List Management Scrambling On E Service Field Clock Bit Locked D unframed sequence 3 2 3 Settings PLCP P H Format CCK PBCC framed mode Selects the packet type PPDU format with long or short PLCP physical layer conver gence protocol Depending on the format selected the structure modulation and data rate of the PLCP preamble and header are modified The format currently set is shown in the graphic display in the lower part of the menu See chapter 2 2 Physical Layer CCK PBCC on page 14 for description of the long and short format Remote command SOURce lt hw gt
85. ren nneen ense tnn ETa 82 SOURce lt hw gt BB WLAN PSDU DLENgth in SOURce hw BB WLAN PSDU MAC ADDRess ch essent nene rennen eterne ens 83 SOURce hw BB WLAN PSDU MAC ADDRess ch STATe sse rennen eene 83 SOURceshw BB WLAN PSDU MAGC DID teen t tart ar th ane tnnt rere prit retis 83 SOURceshw BB WEAN PSDU MAQGC FEGONIrOl enki arb aha Eben bor ek cn rb ena Fes CR a 84 SOURce hw BB WLAN PSDU MAC FCONtrol FDS esee nennen 84 SOURce hw BB WLAN PSDU MAC FCONtrol MDATGa eese ene 84 SOURce hw BB WLAN PSDU MAC FCONtrol MFRagments eese 84 SOURce hw BB WLAN PSDU MAC FCONtrol ORDer sess eene 84 SOURce hw BB WLAN PSDU MAC FCONtrol PMANagement esses 84 SOURce hw BB WLAN PSDU MAC FCONtrol PVERSion essere 84 SOURce lt hw gt BB WLAN PSDU MAC FCONtrol RETRy SOURce lt hw gt BB WLAN PSDU MAC FCONtrol SUBType SOURce lt hw gt BB WLAN PSDU MAC FCONtrol TDS eese nennen SOURce lt hw gt BB WLAN PSDU MAC FCONtrol TYPE spirene eene nnns SOURce hw BB WLAN PSDU MAC FCONItrol WEP sse nennen LSOUbRce bwzsBBWL AN PGSDUMAC FC ZeouenceGfAte rennen 85 SOURce hw BB WLAN PSDU MAC SCONItrol FRAGment INCRement sess 85 SOURce hw BB WLAN PSDU MAC SCONItrol FRAGment STARt S
86. riation on page 39 Trigger Settings EXTernal lt ch gt The numeric suffix to EXTernal lt ch gt distinguishes between the external trigger via the TRIGGER 1 suffix 1 and TRIGGER 2 suffix 2 connector SOURce hw BB WLAN TRIGger ARM EXEQCuUte esses 66 LSOURce lt hw gt l BB WLAN TRIGger EXECUTE rennen nennen nennen 67 SOURce hw BB WLAN TRIGger EXTernal SYNChronize OUTPut eee 67 SOURce hw BB WLAN TRIGger OBASeband DELay eee 68 SOURce hw BB WLAN TRIGger OBASeband INHibit eee 68 LSOUbRcechwzslBBWL AN TRlGoerbRMODe AA 69 E SOURGCeshw E BBAWEAN TRIGSer SLENoglfi uoo rte a tt rere 69 SOURce hw BB WLAN TRIGger SLUNIt eee eene nennen nennen 70 LSOURce lt hw gt BB WLAN TRIGJer SOURCE enne nnne ETE 70 LSOUbRcechwz DBB WL AN TRlGoerl EN TemalzchztDEI aw 71 SOURce shw BB WLAN TRIGger EXTernal ch INHibit eese 71 SOURce hw BB WLAN TRIGger SEQuence essere 71 SOURce lt hw gt BB WLAN TRIGger ARM EXECute The command stops signal generation for trigger modes Armed_Auto and Armed_Ret rigger A subsequent internal or external trigger event restart signal generation Trigger Settings Example BB WLAN TRIG SOUR INT sets internal triggering BB WLAN TRIG SEQ ARET sets Armed Retrigger mode i e every trigger event causes sig nal generation to resta
87. rn for the PATTern selection The maximum length is 64 bits Parameters lt Pattern gt 64 bit pattern RST 0 Example BB WLAN PSDU MAC DATA PATT H3F 8 defines the bit pattern Manual operation See PSDU Data Sorce on page 31 SOURce lt hw gt BB WLAN PSDU DLENgth lt Dlength gt The command sets the data length in bytes In the framed mode data field lengths of up to 4095 bytes are possible This corresponds to the maximum data length The unframed mode offers a data length of up to 100000 bytes If the data field length is changed the generator calculates the number of OFDM data symbols as a function of the set PSDU bit rate SOURce lt hw gt BB WLAN PSDU SCOunt Parameters lt Dlength gt float Range 0 to 4095 Bytes framed 100000 Bytes unframed RST 100Bytes OFDM 1024Bytes CCK PBCC Example BB WLAN PSDU DLEN 256 sets a data length of 256 Manual operation See Data Length on page 31 PSDU Settings SOURce lt hw gt BB WLAN PSDU MAC ADDRess lt ch gt Address The command enters the value of the address fields 1 4 Exactly 48 bits must be entered Each address is 6 bytes 48 bit long The addresses can be entered in hexa decimal form in the entry field of each address field The least significant byte LSB is in left notation The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Address gt integer
88. rrection The next stage performs the actual modulation of the individual OFDM carriers Depending on the set data rate the useful carriers are subjected to a uniform BPSK QPSK 16QAM or 64QAM modulation This is done by first calculating the and Q coefficients of each carrier Gray coding is used to distribute the data bits to constella tion points All carriers from 26 to 26 except carriers 21 7 0 7 and 21 are used for the transmission of user data Carrier number 0 directly at the center frequency later on is not used and is always 0 The remaining 4 are BPSK modulated pilots The pilot carriers change their phase with each symbol The phase variation is determined by the 127 bit PN sequence already defined as scrambling sequence The actual OFDM modulation is performed by inverse discrete Fourier transform IFFT in the next step A 64 point IFFT is carried out with the and Q coefficients of the sub carriers obtained before To ensure sufficient spacing of aliasing products only 52 of the 64 possible carriers are used The result is a discrete complex time signal in the baseband with modulated OFDM carriers A guard field which corresponds to a peri odic continuation of the same symbol is then appended before each OFDM symbol Multipath propagation can thus be easily compensated in the receiver Aliasing products are suppressed by oversampling converting the discrete digital sig nal to an analog signal and subsequent filtering
89. rror free transmission of 50 packets no packet retransmission is to be simulated The sequence number should be incremented by 1 for each packet Since no packet is fragmented the fragment counter can always remain at O In this case the following values have to be set idress 2 hex Address 3 hex Address 4 hex Enable v Enable v jooo ACT BED2 foo2 3ED3 4290 Enable 100 0000 0000 If it is to be simulated that some packets are received incorrectly or if the response of the receiver should be tested when the same packet arrives several times the number of packets required to increment the sequence number can be set to 2 for example Each packet will then automatically be sent twice with identical data Remote command SOURce lt hw gt BB WLAN PSDU MAC SCONtrol STATe on page 86 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol FRAGment STARt on page 85 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol SEQuence STARt on page 86 SOURce hw BB WLAN PSDU MAC SCONtrol FRAGment INCRement on page 85 SOURce hw BB WLAN PSDU MAC SCONtrol SEQuence INCRement on page 86 PPDU Graph Start Number Sets the start number of the fragment bits or the sequence bits of the sequence con trol Remote command SOURce lt hw gt BB WLAN PSDU MAC SCONtrol FRAGment STARt on page 85 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol SEQue
90. rt BB WLAN TRIG EXEC executes a trigger signal generation is started BB WLAN TRIG ARM EXEC signal generation is stopped BB WLAN TRIG EXEC executes a trigger signal generation is started again Usage Event Manual operation See Arm on page 43 SOURce lt hw gt BB WLAN TRIGger EXECute The command executes a trigger The internal trigger source must be selected using the command BB WLAN TRIG SOUR INT and a trigger mode other than AUTO must be selected using the command BB WLAN TRIG SEQ Example BB WLAN TRIG SOUR INT sets internal triggering BB WLAN TRIG SEQ RETR sets Retrigger mode i e every trigger event causes signal generation to restart BB WLAN TRIG EXEC executes a trigger Usage Event Manual operation See Execute Trigger on page 26 SOURce lt hw gt BB WLAN TRIGger EXTernal SYNChronize OUTPut Output enabled for Trigger Source External Enables disables output of the signal synchronous to the external trigger event For R amp S SMBV instruments See also section Sync Output to External Trigger for a detailed description of the applications of this setting Parameters Output Example Manual operation Trigger Settings 0 1 OFF ON ON The signal calculation starts simultaneously with the external trigger event but because of the
91. s the maximum marker delay for set ting BB WLAN TRIG OUTP DEL FIX ON Return values Maximum float Range 0 to max Example BB WLAN TRIG OUTP DEL FIX ON restricts the marker signal delay setting range to the dynamic range BB WLAN TRIG OUTP DEL MAX queries the maximum of the dynamic range Response 2000 the maximum for the marker delay setting is 2000 chips Usage Query only Manual operation See Current Range without Recalculation on page 47 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt DELay MINimum for R amp S SMx AMU instrumenets only The command queries the minimum marker delay for set ting BB WLAN TRIGger OUTPut DELay FIXed ON Return values Minimum float Range 0 to max Example BB WLAN TRIG OUTP DEL FIX ON restricts the marker signal delay setting range to the dynamic range BB WLAN TRIG OUTP DEL MIN queries the minimum of the dynamic range Response 0 the minimum for the marker delay setting is O chips Usage Query only Manual operation See Current Range without Recalculation on page 47 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt MODE Mode Defines the signal for the selected marker output Marker Settings Parameters Mode RESTart FRAMe FACTive PULSe PATTern RATio TRIGger RESTart A mar
92. s the signal genera tion process Physical Layer IandQ 11 Meps Comung from data link layer MAC sub layer Fig 2 1 Principle of 802 11b g signal generation Depending on the PLCP PPDU format used the PLCP preamble and the PLCP header are combined in the packet builder The PSDU field of the packet is filled with the input data of the physical layer block In the next step all the packet data is scram bled The actual spreading and modulation of the data signal to the resulting chip rate of 11 Mcps comes next However the data rates and modulations of the individual fields of a packet can differ The PLCP preamble always has a data rate of 1 Mbps and is DBPSK modulated Besides the actual modulation spreading to the resulting chip rate occurs The PLCP header is either treated exactly like the preamble long PLCP PPDU for mat or DQPSK modulated at a data rate of 2 Mbps short PLCP PPDU format Data rates 1 Mbps 2 Mbps 5 5 Mbps 11 Mbps etc with different modulations can be used for the data part of the packet the PLCP service data unit PSDU The following table gives an overview of the different combinations of data rates modulations and spreading coding methods Data Spreading and Modulation CCK PBCC 2 3 1 2 3 2 Packet field Data rate Chip rate Spreading coding Modulation methods Short PLCP pream 1 Mbps 11 Mcps 11 chip Barker DBPSK ble Sequence Long
93. sfer The data packets are transmitted and received on the same frequency in time division duplex TDD but without a fixed timeslot raster An 802 11 component can only trans mit or only receive packets at any particular time The R amp S Signal Generator simulates IEEE 802 11a g WLAN at the physical on the physical layer Two simulation modes are offered In the framed mode a sequence of data packets with the frame structure defined by the standard is generated A MAC header and a frame check sequence can be activated In the unframed time mode a non packet oriented signal without frame structure is generated with the modulation modes and data rates defined by the IEEE 802 11 The following list gives an overview of the options provided by the R amp S Signal Genera tor for generating a IEEE 802 11a g WLAN signal e Physical Layer modes OFDM IEEE 802 11a g and CCK PBCC IEEE 802 11b g Operating Manual 1171 5283 12 15 9 Physical Layer OFDM e Chip Sample rate 20 Mcps OFDM IEEE 802 11a g and 11 Mcps CCK PBCC IEEE 802 11b g e PSDU bit rates 1Mbps 2Mbps 5 5Mbps and 11 Mbps CCK PBCC 22Mbps PBCC 6 Mbps 9 Mbps 12 Mbps 18 Mbps 24Mbps 36 Mbps 48 Mbps and 54 Mbps OFDM e PSDU Modulation DBPSK DQPSK and CCK PBCC CCK PBCC and BPSK QPSK 16QAM or 64QAM OFDM depending on specified PSDU bit rate Data scrambling can be activated or deactivated CCK PBCC and initial scrambler state can be set randomly or to
94. subsequent trigger event causes a restart RST AUTO Example BB WLAN SEQ AAUT sets the Armed auto trigger mode the device waits for the first trigger e g with TRG and then generates the signal continu ously Manual operation See Trigger Mode on page 42 4 4 Marker Settings This section lists the remote control commands necessary to configure the markers OUTPut lt ch gt The numeric suffix to OUTPut distinguishes between the available markers Only two markers are available for the R amp S SMBV i e the allowed values for the suffix are 1 or 2 TSOUbRcechwz DBB WL AN TRilGoer OUT but D I av FlSed A 73 SOURce lt hw gt BB WLAN TRIGger OUTPut lt ch gt D I au 73 SOURce shw BB WLAN TRIGger OUTPut ch DELay MAXimum sees 73 SOURce shw BB WLAN TRIGger OUTPut ch DELay MlNimum eene 74 Marker Settings SOURce hw BB WLAN TRIGger OUTPut ch MODPBE 22 etta nne euh nnns 74 SOURce shw BB WLAN TRIGger OUTPut ch ONTime eese 75 SOURceshw BB WLAN TRIGger OUTPut ch OFFTime eene eene 75 SOURce hw BB WLAN TRIGger OUTPut ch PAT rem ahorro rona nunt innu 76 SOURce shw BB WLAN TRIGger OUTPut ch PULSe DIVider eeeeeeeeseees 76 SOURce shw BB WLAN TRIGger OUTPut ch PULSe FREQuency esses 76 SOURce lt hw gt BB WLAN TRIGger OUTPut DELay
95. suffix 2 connector Parameters lt Inhibit gt float Range 0 to 67108863 Increment 1 chip RST 0 Example BB WLAN TRIG SOUR EXT selects an external trigger via the TRIGGER 1 connector BB WLAN TRIG INH 200 sets a restart inhibit for 200 chips following a trigger event Manual operation See Trigger Inhibit on page 45 SOURce hw BB WLAN TRIGger SEQuence Sequence The command selects the trigger mode Marker Settings Parameters Sequence AUTO RETRigger AAUTo ARETrigger SINGle AUTO The modulation signal is generated continuously RETRigger The modulation signal is generated continuously A trigger event internal or external causes a restart AAUTo The modulation signal is generated only when a trigger event occurs After the trigger event the signal is generated continu ously Signal generation is stopped with command SOUR BB WLAN TRIG ARM EXEC and started again when a trigger event occurs ARETrigger The modulation signal is generated only when a trigger event occurs The device automatically toggles to RETRIG mode Every subsequent trigger event causes a restart Signal generation is stopped with command SOUR BB WLAN TRIG ARM EXEC and started again when a trigger event occurs SINGle The modulation signal is generated only when a trigger event occurs Then the signal is generated once to the length specified with command SOUR BB WLAN TRIG SLEN Every
96. t hw gt BB WLAN TRIGger SOURce Source Selects the trigger source Parameters lt Source gt INTernal OBASeband BEXTernal EXTernal INTernal manual trigger or TRG EXTernal BEXTernal trigger signal on the TRIGGER 1 2 connector OBASeband trigger signal from the other path RST INTernal Trigger Settings Example SOURCe1 BB WLAN TRIGger SOURce EXTernal sets external triggering via the TRIGGER 1 connector Manual operation See Trigger Source on page 43 SOURce lt hw gt BB WLAN TRIGger EXTernal lt ch gt DELay Delay The command specifies the trigger delay expressed as a number of chips for external triggering The numeric suffix to EXTernal distinguishes between the external trigger via the TRIGGER 1 suffix 1 and TRIGGER 2 suffix 2 connector Parameters Delay float Range 0 0 to 65535 0 Increment 1 chip RST 0 0 Example BB WLAN TRIG SOUR EXT sets an external trigger via the TRIGGER 1 connector BB WLAN TRIG DEL 50 sets a delay of 50 chips for the trigger Manual operation See Trigger Delay on page 45 SOURce lt hw gt BB WLAN TRIGger EXTernal lt ch gt INHibit lt Inhibit gt The command specifies the number of chips by which a restart is to be inhibited follow ing a trigger event This command applies only in the case of external triggering The numeric suffix to EXTernal distinguishes between the external trigger via the TRIGGER 1 suffix 1 and TRIGGER 2
97. terest Simulation Mode Unframed m unframed sequence No PLCP preamble and no signal field are generated in the unframed mode The idle time is also omitted The data field is identical to that of the framed mode and also contains the service and tail bits The length limitation stipulated by the standard to the maximum PSDU block length of 4095 bytes in the framed mode does not apply Operation is the same as in the framed mode but only a limited num ber of setting parameters is available Remote command SOURce lt hw gt BB WLAN SMODe on page 59 Predefined Frames Framed Mode only Selects the frame type The selection defines parameters of the MAC layer e g the type and sub type bit fields of the MAC Header Data Frames containing useful data RTS Request to Send CTS Clear to Send ACK Acknowledgement Remote command SOURce lt hw gt BB WLAN FFORmat on page 53 Sequence Length Sets the sequence length of the signal in number of frames A physical layer frame consists of a PPDU burst including the subsequent idle time Remote command SOURce lt hw gt BB WLAN SLENgth on page 59 Idle time based on standard chip rate This feature is available for Framed Mode only General Settings for WLAN Signals Sets the idle time i e the time between two PPDU bursts Idle time is given in us the packets can also be joined to each other directly with idle time 0 Please note that
98. ters available to the instrument In 802 11a g OFDM mode a cosine filter with roll off factor 0 1 is used by default to achieve the spectrum masks requirement In 802 11b g CCK PBCC mode a gauss FSK filter with B T 0 5 is used by default to achieve the spectrum masks requirement Remote command SOURce hw BB WLAN FILTer TYPE on page 63 3 5 2 Filter Clipping Settings Roll Off Factor BxT Sets the filter parameter The filter parameter offered Roll Off Factor or BxT depends on the currently selected filter type This parameter is preset to the default for each of the predefined filters Remote command SOURce lt hw gt BB WLAN FILTer PARameter APCO25 on page 63 SOURce lt hw gt BB WLAN FILTer PARameter COSine on page 64 SOURce lt hw gt BB WLAN FILTer PARameter GAUSs on page 64 SOURce lt hw gt BB WLAN FILTer PARameter RCOSine on page 65 SOURce lt hw gt BB WLAN Filter PARameter SPHase on page 65 SOURce lt hw gt BB WLAN FILTer PARameter PGAuss on page 65 Cut Off Frequency Factor available for filter parameter Lowpass only Sets the value for the cut off frequency factor The cut off frequency of the filter can be adjusted to reach spectrum mask requirements Remote command SOURce lt hw gt BB WLAN FILTer PARameter LPASs on page 64 SOURce lt hw gt BB WLAN FILTer PARameter LPASSEVM on page 65
99. th OFDM the individual carriers are superimposed mutually orthogonal which in the ideal case does not cause any intercarrier interference ICI The CCK complementary code keying physical layer mode is used for the 5 5 Mbps and 11 Mbps data rates The PBCC packet binary convolutional coding physical layer can optionally be used instead of CCK modulation and extents 802 11b to higher data rates 22 Mbps Remote command SOURce lt hw gt BB WLAN MODE on page 54 Simulation Mode Selects the simulation mode Framed The framed mode is the standard operating mode which is also used in the real system Data packets with the frame structure defined by the standard are generated Simulation Mode Framed m Predefined Frames Data Signals representing a sequence of frames PLCP protocol data units referred to as PPDUs and separated by a so called idle time can be configured in the framed mode The user data is continued in the consecutive frames i e it is not repeated in each frame Both the duration of the idle time and the number of frames to be sent can be user selected General Settings for WLAN Signals Unframed The unframed mode is offered in addition In this mode a non packet oriented signal without a frame structure is generated with the modulations and data rates defined by 802 11a g This mode can be used for simple tests for which only modulation and spectrum of the test signal are of in
100. the counter of the frag ment bits Manual operation See Sequence Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol FRAGment STARt Start The command enters the start number of the fragment bits of the sequence control The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMedQ Parameters Start integer Range H0 4 to SUE A RST HO0 04 PSDU Settings Example BB WLAN PSDU MAC SCON FRAG STAR H4 4 sets the start value of the fragment bits of the sequence control Manual operation See Sequence Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol SEQuence INCRement lt Increment gt Defines the number of packets required to increment the counter of the sequence bits of the sequence control The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Increment gt float Range 0 to 1024 RST 1 Example BB WLAN PSDU MAC SCON FRAG INCR 2 two packets are required to increment the counter of the sequence bits Manual operation See Sequence Control on page 35 SOURce lt hw gt BB WLAN PSDU MAC SCONtrol SEQuence STARt Start The command enters the start number of the fragment bits of the sequence control The MAC header can only be configured in framed mode SOURce BB WLAN SMODe FRAMed Parameters lt Start gt integer Range H0 12 to HFFF 12 RST H0 12 Example BB WLAN P
101. the effect of a trigger event on the signal genera tion e Auto The signal is generated continuously e Retrigger The signal is generated continuously A trigger event internal or external causes a restart Armed Auto The signal is generated only when a trigger event occurs Then the signal is gener ated continuously An Arm stops the signal generation A subsequent trigger event internal with or external causes a restart Armed Retrigger The signal is generated only when a trigger event occurs Then the signal is gener ated continuously Every subsequent trigger event causes a restart An Arm stops signal generation A subsequent trigger event internal with or external causes a restart e Single The signal is generated only when a trigger event occurs Then the signal is gener ated once to the length specified at Signal Duration Every subsequent trigger event internal or external causes a restart Remote command SOURce lt hw gt BB WLAN TRIGger SEQuence on page 71 Signal Duration Defines the length of the signal sequence to be output in the Single trigger mode The input is to be expressed in chips It is possible to output deliberately just part of the signal an exact sequence of the sig nal or a defined number of repetitions of the signal Remote command SOURce hw BB WLAN TRIGger SLENgth on page 69 SOURce lt hw gt BB WLAN TRIGger SLUNit on page 70
102. the input impedance of the trigger signal Remote command SOURce lt hw gt BB WLAN TRIGger SOURce on page 70 Sync Output to External Trigger enabled for Trigger Source External Enables disables output of the signal synchronous to the external trigger event For R amp S SMBV instruments For or two or more R amp S SMBVs configured to work in a master slave mode for syn chronous signal generation configure this parameter depending on the provided sys tem trigger event and the properties of the output signal See the table below for an overview of the required settings Trigger Marker Clock Settings Table 3 1 Typical Applications System Trigger Application Sync Output to External Trig ger Common External Trigger event All instruments are synchronous ON for the master and the slave to the external trigger event instruments All instruments are synchronous OFF among themselves but starting the signal from first symbol is more important than synchronicity with external trigger event Internal trigger signal of the mas All instruments are synchronous OFF ter R amp S SMBV for the slave among themselves instruments On Corresponds to the default state of this parameter The signal calculation starts simultaneously with the external trigger event but because of the instrument s processing time the first sam ples are cut off and no signal is outputted After elapsing of the inter na
103. the trigger inhibit can be set separately for each of the two paths Remote command SOURce hw BB SOURce hw BB AN TRIGger EXTernal ch INHibit on page 71 AN TRIGger OBASeband INHibit on page 68 zi Trigger Marker Clock Settings 3 6 2 Marker Mode The marker output signal for synchronizing external instruments is configured in the marker settings section Marker Mode The R amp S SMBV supports only two markers Marker Mode Selects a marker signal for the associated MARKER output Restart A marker signal is generated at the start of each signal sequence period selected number of frames Frame Start A marker signal is generated at the start of each frame period PPDU idle time Frame Active A marker signal is generated at the start of every active part of the frame The active data transfer part PPDU of a frame period is marked with high the inactive part idle time with low This marker can be used to decrease the carrier leakage during inactive signal parts by feeding it into the pulse modulator Pulse A regular marker signal is generated The pulse frequency is defined by entering a divider The frequency is derived by dividing the sample rate by the divider The input box for the divider opens when Pulse is selected and the resulting pulse frequency is displayed below it Remote command SOURce hw BB WLAN TRIGger OUTPut ch PULSe DIVider on
104. to 8096 of this maximum level BB WLAN CLIP STAT ON activates level clipping See Clipping Mode on page 40 SOURce lt hw gt BB WLAN CLIPping STATe State The command activates level clipping Clipping The value is defined with the com mand SOURce BB WLAN CLIPping LEVel the mode of calculation with the com mand SOURce BB WLAN CLIPping MODE Parameters lt State gt Example Manual operation 0 1 OFF ON RST OFF BB WLAN CLIP STAT ON activates level clipping See Clipping State on page 39 SOURce lt hw gt BB WLAN FILTer TYPE Type The command selects the filter type Parameters lt Type gt Example Manual operation RCOSine COSine GAUSs LGAuss CONE COF705 COEQualizer COFequalizer C2K3x APCO25 SPHase RECTangle PGAuss LPASs DIRac ENPShape EWPShape LPASSEVM RST Depends on layer mode BB WLAN FILT TYPE COS sets the filter type COSine See Filter on page 38 SOURce lt hw gt BB WLAN FILTer PARameter APCO25 lt Apco25 gt The command sets the roll off factor for filter type APCO25 Parameters lt Apco25 gt float Range 0 05 to 0 99 Increment 0 01 RST 0 2 Filter Clipping Settings Example BB WLAN PAR APCO25 0 2 sets the roll off factor to 0 2 for filter type APCO25 Manual operation See Roll Off Factor BXT on page 39 SOURce lt hw gt
105. via the CLOCK connector Multiple A multiple of the chip clock is supplied via the CLOCK connector the chip clock is derived internally from this The Multiplier window provided allows the multiplication factor to be entered Remote command SOURce lt hw gt BB WLAN CLOCk MODE on page 77 Chip Clock Multiplier Enters the multiplication factor for clock type Multiple Remote command SOURce lt hw gt BB WLAN CLOCk MULTiplier on page 77 Trigger Marker Clock Settings Measured External Clock Provided for permanent monitoring of the enabled and externally supplied clock signal Remote command CLOCk INPut FREQuency 3 6 5 Global Settings The buttons in this section lead to dialogs for general trigger clock and mapping set tings Global Trigger Clock Settings Calls the Global Trigger Clock Input Settings dialog This dialog is used among other things for setting the trigger threshold the input impe dance and the polarity of the clock and trigger inputs The parameters in this dialog affect all digital modulations and standards and are described in chapter Global Trigger Clock Input Settings in the Operating Manual User Marker AUX UO Settings Calls the User Marker AUX I O Settings dialog used to map the connector on the rear of the instruments See also User Marker AUX I O Settings in the Operating Manual Trigger Marker Clock Settings 4 Remote Control Commands The following comm
106. ytes as in the Framed mode Moreover the data stream can be scrambled prior to the modulation Scrambling Mode parameter 3 2 1 Standard 802 11a OFDM In the upper section of the menu the parameters of the data part PSDU are set In the middle section the parameters of the scrambler and interleaver are set A graph in the lower sections illustrates the structure of the PPDU framed mode or the unframed sequence unframed mode e Framed mode PPDU Sequence Configuration SC IEEE 802 11a OFDM WLAN PPDU Configuration PSDU Bit Rate OFDM 54 Mbps v PSDU Modulation Data Length 100 bytes Number of Data Symbols ti 4 PSDU Data Source PRBS9 zf Data List Management Scrambling On Random Init Scrambler Init hex Interleaver Active Iv Service Field hex Time Domain Windowing Active Transition Time Configure MAC Header and FCS PLCP Header Coded OFDM Coded OFDM BPSK r 1 2 Rate is indicated in Signal PPDU e Unframed mode E5 IEEE 802 11g OFDM WLAN A Sequence Configuration PSDU Bit Rate OFDM 54 Mbps PSDU Modulation Data Length 1 024 bytes D Number of Data Symbols 39 PSDU Data Source PRBS 9 Data List Management Scrambler On User Init Scrambler Init hex 01 Interleaver Active V Service Field hex 0000 Time Domain Windowing Active I Transition Time 100 ns 3 2 2 Standard 802 11b g CCK PBCC In the upper section of the menu the

K248 IEEE 802.11 (a/b/g)

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