<EDGE Looped based BER and TX measurements using ARB files on the R&S CMW 500> Application Note Products: R&S CMW500 R&S CMW- KW200 R&S CMW- KM200 <Application Note> <Thomas Lutz> <05.2010-1CM89>-<version 0.1>
Table of Contents Table of Contents 1... 4 1.1 R&S CMW500 GSM Arbitrary Waveform Playback Setup...4 1.1.1 Step 1 Enable the General Purpose RF Generator...4 1.1.2 Step 2 Configure the General Purpose RF Generator...5 1.1.3 Step 3 Select the ARB File...5 1.1.4 Step 4 Turn ON the General Purpose RF Generator...6 1.1.5 Table of the General Purpose RF Generator Settings...7 1.1.6 Rohde & Schwarz GSM Non-signaling test arbitrary waveform configuration...7 1.1.6.1 Other setup notes...10 1.1.7 R&S CMW500 Configuration for GSM Uplink Signal Measurement...10 1.1.8 Multi Evaluation Settings...11 1.1.9 RF Settings...11 1.1.10 Measurement Control...15 1.1.10.1 Repetition...15 1.1.10.2 Stop Condition...16 1.1.10.3 Statistic Counts...16 1.1.10.4 Measurement Slots...16 1.1.10.5 Assign View...17 1.1.11 Start the Measurement...17 1.1.12 Measurement Results Screen Shots...17 1.1.13 Automating a GSM Measurement with the R&S CMW500...19 1.1.13.1 Configure the arbitrary signal generator to play the waveform...19 1.1.13.2 Configure the R&S CMW500 analyzer to make a GSM measurement.20 1.1.13.3 Configure the trigger condition for the GSM measurement...20 1.1.13.4 Arm the measurement...20 1.1.13.5 Get the power measurement results...21 1.1.13.6 Get the averaged modulation measurement results...21 1.1.13.7 Get the spectrum measurement results...21 1.1.13.8 Get the BER measurement results...21 2 Summary... 21 3 References... 21 using ARB files on the R&S CMW 500> 2
Table of Contents using ARB files on the R&S CMW 500> 3
1 1.1 R&S CMW500 GSM Arbitrary Waveform Playback Setup The following details how to configure the CMW500 General Purpose RF Generator for playback of an arbitrary waveform used for GSM non-signaling BER looped back testing, using a 8PSK modulation. The waveform to execute playback on is: D:\Rohde-Schwarz\CMW\Data\waveform\SRB_8PSK_1040.wv 1.1.1 Step 1 Enable the General Purpose RF Generator using ARB files on the R&S CMW 500> 4
1.1.2 Step 2 Configure the General Purpose RF Generator 1.1.3 Step 3 Select the ARB File To select the arbitrary waveform, press the ARB soft key on left side of R&S CMW screen, followed by the Select ARB File soft key on the bottom using ARB files on the R&S CMW 500> 5
Navigate through the pop up dialog, e.g. rotating the spin wheel and select the desired arbitrary waveform file by pushing the spin wheel. Navigate the focus of the dialog to the OK button by rotating the spin wheel again. After selecting the OK button push the spin wheel again 1.1.4 Step 4 Turn ON the General Purpose RF Generator To begin playing the arbitrary waveform, press the On/Off hard key button on the R&S CMW500 front panel, located along the top of the instrument, above the spin wheel. using ARB files on the R&S CMW 500> 6
1.1.5 Table of the General Purpose RF Generator Settings General Purpose RF Generator RF Configuration Parameter Settings Units RF Routing User defined (suggest RF1 COM) External Attenuation User defined (RF cable path loss) db Frequency 941.4 MHz Level (RMS) -65.0 (during synchronization) -86.0 or -88.0 (during BER measurements) dbm Digital Gain 0.0 db List Mode Baseband Configuration Baseband Mode Dual Tone ARB Configuration Repetition ARB File Name Trigger Retrigger Autostart Source List Configuration List Elements Off ARB Not applicable Continuous D:\Rohde-Schwarz\CMW\Data\waveform\ SRB_8PSK_1040.wv Checked Checked Not applicable Not applicable 1.1.6 Rohde & Schwarz GSM Non-signaling test arbitrary waveform configuration The waveform described below is useful for testing GSM chipsets in non-signaling test mode using the Rohde & Schwarz CMW500 Wideband Radio Communication Tester. The signal provides everything needed in a downlink signal for a non-signaling test mode enabled device under test to synchronize and decode on channel 32.. The signal can be used to perform looped back based BER measurements together with TX measurements on the R&S CMW 500. The tests could also be done as single ended BER tests, using a different ARB file, which is described in another application note 1CM90_0e.pdf. using ARB files on the R&S CMW 500> 7
Uplink signal measurements from the chip can be performed using the CMW500 GSM measurement option, KM200. Waveform file name: SRB_8PSK_1040.wv Waveform Content 4800 millisecond long waveform (1040 frames) A BCCH channel, containing a 51 multi-frame structure on slot 0 Seven parallel signals, running a PDTCH 52 multi-frame structure on slots 1 to 7 Providing multi-slot support 8 PSK modulated, uncoded data, but valid MCS9 header The traffic data is random, but repeating every block BCCH and PDTCH channels are transmitted with the same power Base station color code 0 The next graphic illustrates the frame structure of the signal. Timing wise, starting with slot 0 of frame 0 a frequency correction burst (FCC) is transmitted followed by a traffic channel (TCH) on slot 1 of frame 0. The signal on slot 0 represents a complete C0 multi-frame signal. With the wrap around of the ARB signal on frame 1039 the BCCH multi-frame is incomplete, as 1040 frames are not dividable by 51 without a reminder. The length of the traffic channel (TCH) signals are 40 TCH multi-frames long (40 x 26 = 1040 frames), before the signal wraps around. The signal content of slot 1 to slot 7 is identical. using ARB files on the R&S CMW 500> 8
Frame 0 Frame 1 Frame 2 Frame 3 Frame 4 Frame 5 Frame 6 Frame 7 Frame 8 Frame 9 Frame 10 Frame 11 Frame 12 Frame 13 Frame 14 Frame 15 Frame 16 Frame 17 Frame 18 Frame 19 Frame 20 Frame 21 Frame 22 Frame 23 Frame 24 Frame 25 Frame 26 Frame 27 Frame 28 Frame 29 Frame 30 Frame 31 Frame 32 Frame 33 Frame 34 Frame 35 Frame 36 Frame 37 Frame 38 Frame 39 Frame 40 Frame 41 Frame 42 Frame 43 Frame 44 Frame 45 Frame 46 Frame 47 Frame 48 Frame 49 Frame 50 Frame 51 Frame 52 Frame 53 Frame 54 Frame 55 Frame 56 Frame 57 Frame 58 Frame 59 Frame Slot 0 FCC SYNC BCC BCC BCC BCC FCC SYNC FCC SYNC FCC SYNC FCC SYNC IDLE 1 FCC SYNC BCC BCC BCC BCC Slot 1 Slot 2 Slot 3 Slot 4 Slot 5 Slot 6 Slot 7 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 Frame 1039 Frame 0 FCC IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 IDLE 1 1) The IDLE is replaced by random data using ARB files on the R&S CMW 500> 9
1.1.6.1 Other setup notes It is required to have the BCCH and the TCH at the same channel and the same level 1.1.7 R&S CMW500 Configuration for GSM Uplink Signal Measurement The following describes how to configure the R&S CMW500 to perform a measurement on the uplink GSM transmitter. First, enable the GSM TX Measurement option on, by checking its enable radio button from the Measurement Controller sub panel. This menu can be found by pressing the Measure hard key found along the top of the R&S CMW500 front panel, above the number keypad. using ARB files on the R&S CMW 500> 10
1.1.8 Multi Evaluation Settings Next find and press the following soft key on from the CMW500 GSM TX Measurement Multi Evaluation screen. If this soft key is not yet visible, use the Tasks hard key. The Tasks hard key shows the available currently enabled (loaded) software features and to select this feature. Press the soft key GSM Multi Eval. The displayed soft keys row along the bottom of the LCD display should change to one of the GSM Multi Evaluation controls like shown below. 1.1.9 RF Settings Press the Config on the right side of the displayed soft keys row along the bottom of the LCD display. You should see the shown pop up menu now. using ARB files on the R&S CMW 500> 11
Use the spin wheel to scroll down in the configuration pop up window to the position, where the BER parameter become visible. Change the BER loop type to SRB using ARB files on the R&S CMW 500> 12
The following screen shots detail how to configure the following parameters to these values: using ARB files on the R&S CMW 500> 13
GSM Measurements RF Configuration Parameter Settings Units RF Routing User defined (suggest RF1 COM) External Attenuation User defined (RF cable path loss) db Frequency 896.4 MHz Expected Power Level (RMS) 13.0 dbm User Margin 5.0 db List Mode Trigger Trigger Source Trigger Slope Off Power Rising Edge Trigger Threshold -30.0 db Trigger Delay 0 slots Trigger Timeout 1000 (default) msec. Minimum Trigger Gap 1 slot Statistic Counts Power 1 Frames Modulation 5 Frames Spectrum due to Switching Spectrum due to Modulation 10 Frames 30 Frames BER 88 (corresponds to 10 ksymbols) Frames List Configuration List Elements Not applicable Press the soft key Config again to come back to the measurement screen. The R&S CMW500 LCD screen should look like the following: using ARB files on the R&S CMW 500> 14
1.1.10 Measurement Control Find and press the following soft key on the right-hand column of the LCD screen. Configure the remaining parameters by manipulating the soft keys as such: 1.1.10.1 Repetition Set the repetition mode to Continuous using ARB files on the R&S CMW 500> 15
1.1.10.2 Stop Condition Set the stop condition to None 1.1.10.3 Statistic Counts 1.1.10.4 Measurement Slots using ARB files on the R&S CMW 500> 16
1.1.10.5 Assign View Press the soft key Assign Views to select the TX measurements of your interest, including a loop based BER 1.1.11 Start the Measurement The measurement can be manually executed (triggered) by pressing the ON/OFF hard key on the front panel of the R&S CMW500, located along the top of the instrument, above the spin wheel. 1.1.12 Measurement Results Screen Shots using ARB files on the R&S CMW 500> 17
A successful GSM multi-evaluation measurement on the R&S CMW500 should look something like found on the following screen shot. Find and press the following soft key on the right-hand column of the LCD screen. In combination with the soft key Select View on the bottom of the display more details for single TX measurements can be visualized. The following screen shots demonstrate such measurement views using ARB files on the R&S CMW 500> 18
1.1.13 Automating a GSM Measurement with the R&S CMW500 The following SCPI command code is an example of how to configure the R&S CMW500 signal generator and signal analyzer to perform a non-signaling GSM uplink TX measurement on non signaling enabled GSM chipset. The leading CMW: is not part of the command, this is only used as a address symbol in Rohde & Schwarz remote script tools. 1.1.13.1 Configure the arbitrary signal generator to play the waveform Whenever loading an ARB file, you should ensure it was present on the selected path. The verification can be achieved by querying the currently loaded ARB file. A return string "No File Selected" would be an indication, that the file is not present. using ARB files on the R&S CMW 500> 19
CMW: ROUT:GPRF:GEN:RFS:CONN RF1C CMW: SOUR:GPRF:GEN:BBM ARB CMW: SOUR:GPRF:GEN:RFS:FREQ 941.4e6 CMW: SOUR:GPRF:GEN:RFS:EATT 1 CMW: SOUR:GPRF:GEN:RFS:LEV -65 CMW: SOUR:GPRF:GEN:ARB:FILE 'd:\\rohde-schwarz\\cmw\\data\\waveform\\srb_8psk_1040.wv' CMW: SOUR:GPRF:GEN:ARB:FILE? CMW: SOUR:GPRF:GEN:ARB:REP CONT CMW: TRIG:GPRF:GEN:ARB:RETR ON CMW: TRIG:GPRF:GEN:ARB:AUT ON CMW: SOUR:GPRF:GEN:LIST OFF CMW: SYST:ERR? CMW: SOUR:GPRF:GEN1:STAT ON;*OPC? 1.1.13.2 Configure the R&S CMW500 analyzer to make a GSM measurement CMW: ROUT:GSM:MEAS:RFS:CONN RF1C CMW: CONF:GSM:MEAS:RFS:EATT 1 CMW: CONF:GSM:MEAS:RFS:FREQ 896.4e6 CMW: CONF:GSM:MEAS:RFS:ENP 13 CMW: CONF:GSM:MEAS:RFS:UMAR 5 CMW: CONF:GSM:MEAS:MEV:MSL 0, 2, 0 CMW: CONF:GSM:MEAS:MEV:SCO:PVT 1 CMW: CONF:GSM:MEAS:MEV:SCO:MOD 5 CMW: CONF:GSM:MEAS:MEV:SCO:SMOD 30 CMW: CONF:GSM:MEAS:MEV:SCO:SSW 10 CMW: CONF:GSM:MEAS:MEV:SCO:BER 88 CMW: CONF:GSM:MEAS:MEV:BER:LOOP SRB CMW: CONF:GSM:MEAS:MEV:TSEQ TSC0 CMW: CONF:GSM:MEAS:MEV:RES:PVT ON CMW: CONF:GSM:MEAS:MEV:RES:EVM OFF CMW: CONF:GSM:MEAS:MEV:RES:MERR OFF CMW: CONF:GSM:MEAS:MEV:RES:PERR ON CMW: CONF:GSM:MEAS:MEV:RES:SMFR ON CMW: CONF:GSM:MEAS:MEV:RES:SMT ON CMW: CONF:GSM:MEAS:MEV:RES:SSFR ON CMW: CONF:GSM:MEAS:MEV:RES:SST ON CMW: CONF:GSM:MEAS:MEV:RES:IQ OFF CMW: CONF:GSM:MEAS:MEV:RES:BER ON 1.1.13.3 Configure the trigger condition for the GSM measurement CMW: TRIG:GSM:MEAS:MEV:SOUR 'Power' CMW: TRIG:GSM:MEAS:MEV:DEL 0 CMW: TRIG:GSM:MEAS:MEV:TOUT 1 CMW: TRIG:GSM:MEAS:MEV:THR -30.00 1.1.13.4 Arm the measurement using ARB files on the R&S CMW 500> 20
Summary CMW: INIT:GSM:MEAS:MEV;*OPC? 1.1.13.5 Get the power measurement results CMW: FETC:GSM:MEAS:MEV:PVT? 1.1.13.6 Get the averaged modulation measurement results CMW: FETC:GSM:MEAS:MEV:MOD:AVER? 1.1.13.7 Get the spectrum measurement results CMW: FETC:GSM:MEAS:MEV:TRAC:SMOD:FREQ? CMW: FETC:GSM:MEAS:MEV:TRAC:SSW:FREQ? 1.1.13.8 Get the BER measurement results CMW: FETC:GSM:MEAS:MEV:BER? 2 Summary The application note explains how to use an arbitrary waveform file to perform typical GSM transmitter tests in parallel to a looped based BER measurements for a nonsignaling test mode enabled device. 3 References [1] User manual of the R&S CMW 500 or R&S CMW 280 radio communication tester. using ARB files on the R&S CMW 500> 21
Index A Arm the GSM Measurement... 20 Automating a GSM Measurement... 19 C Configure the ARB generator... 19 Configure the GPRF Generator... 5 Configure the GSM analyzer... 20 Configure the trigger condition... 20 E Enable the GPRF Generator... 4 G Get the GSM averaged modulation measurement results... 21 Get the GSM BER measurement results... 21 Get the GSM power measurement results... 21 Get the GSM spectrum measurement results... 21 GSM...17 GSM Uplink Measurements...10 M Measurement Control...15 Multi Evaluation Settings...11 R RF Settings of the GSM Measurement...11 S Select the ARB File...5 Select View...18 Start the GSM Measurement...17 T Table of the GPRF Generator Settings...7 Turn On the GPRF Generator...6
About Rohde & Schwarz Rohde & Schwarz is an independent group of companies specializing in electronics. It is a leading supplier of solutions in the fields of test and measurement, broadcasting, radiomonitoring and radiolocation, as well as secure communications. Established 75 years ago, Rohde & Schwarz has a global presence and a dedicated service network in over 70 countries. Company headquarters are in Munich, Germany. Environmental commitment Energy-efficient products Continuous improvement in environmental sustainability ISO 14001-certified environmental management system Regional contact USA & Canada USA: 1-888-TEST-RSA (1-888-837-8772) from outside USA: +1 410 910 7800 CustomerSupport@rohde-schwarz.com East Asia +65 65 13 04 88 CustomerSupport@rohde-schwarz.com Rest of the World +49 89 4129 137 74 CustomerSupport@rohde-schwarz.com This application note and the supplied programs may only be used subject to the conditions of use set forth in the download area of the Rohde & Schwarz website. R&S is a registered trademark of Rohde & Schwarz GmbH & Co. KG. Trade names are trademarks of the owners. Rohde & Schwarz GmbH & Co. KG Mühldorfstraße 15 D - 81671 München Phone + 49 89 4129-0 Fax + 49 89 4129 13777 www.rohde-schwarz.com