Atec R-S-CMU200 - Manual (Page 44)

44 R&S ® CMU200 Universal Radio Communication Tester Version 09.00, October 2008
Remarks
 Due to the modulation schemes used Bluetooth ® and AMPS standards will not be supported.
 The R&S ® CMU-B17 and R&S ® CMU-B73 options use the same mainboard connector of the R&S ® CMU200.
Therefore, either the R&S ® CMU-B17 or the R&S ® CMU-B73 can be ordered for a single instrument.
Additional information for GSM:
To avoid influences on the fading profile, the following is highly recommended:
 To set all timeslots to the same level.
 To use for the TX signal of the R&S ® CMU200 the same RF frequencies and RF levels for both TCH and BCCH.
 To switch off hopping.
Aspects to be considered if TX or RX signal paths are interrupted:
The RF frequency of the R&S ® CMU200 influences the rotating direction of the I/Q vector.
The direction is inverted for f < 1200.1 MHz; this can be compensated for by changing I and Q.
R&S ® CMU200 generator or analyzer RF frequency
100 kHz to 1200.0999999 MHz 1200.1 MHz to 2700.0 MHz
R&S ® CMU200 I/Q output vector inverted rotation
swap I output for Q output for proper
operation normal rotation
R&S ® CMU200 I/Q input vector inverted rotation
swap I input for Q input for proper
operation normal rotation
The rotating direction must be considered if the R&S ® CMU200 signal path from the link handler board to the frontend and vice versa is
interrupted, i.e. if the signal is not returned to the same R&S ® CMU200 block after external handling.
Examples:
 The rotating direction need not be taken into account if the transmitted signal is routed from the I/Q output of the R&S ® CMU-B17 to
an external fading simulator and then returned to the R&S ® CMU200 I/Q input (the R&S ® CMU200 in combination with the
R&S ® ABFS fading simulator or the R&S ® SMIQ/SMIQB14, with the R&S ® CMU200 providing the faded RF signal).
 The rotating direction must be considered if the transmitted signal is forwarded to an external fading simulator and is not returned to
the I/Q input of the R&S
® CMU200 (the R&S ® CMU200 in combination with the R&S ® SMIQ, with the R&S ® SMIQ providing the faded
RF signal).
Notes for measuring I/Q/IF signals applied to inputs of the R&S
®
CMU-B17 option on the
R&S ® CMU200 RX path:
 The RF spectrum analyzer function (RF function group) cannot be used.
 The displayed RF power levels are not related directly to the applied I/Q/IF voltages. The analyzer settings of the R&S ® CMU200
RF interface (RF 1, RF 2, RF 4 IN) must also be considered (Analyzer Level → RF Max. Level).
 I/Q inputs have a fixed attenuation of 2 dB, e.g. the RF power meter readout for an applied 500 mV I/Q peak voltage will be 2 dB
below the value set in RF Max. Level.
 IF inputs do not have a fixed attenuation. The max. IF input level is 2 dBm. The RF power meter readout for the specified
max. IF signal level (2 dBm) will be 2 dB below the value set in RF Max. Level.
 We recommend switching off the autoranging function.
 RF and IF trigger functions are not possible.
 The WCDMA RF compensation filter is switched off (I/Q IN/OUT, IF IN/OUT, IFIN_I/Q IN/OUT).
 WCDMA UE test: ACLR/SEM measurement is not applicable.