Measurements
R&S
®
FSW
177
User Manual 1173.9411.02 ─ 19
5.3.7.1
Measurement Example 1 – ACPR Measurement on an CDMA2000 Signal
Test setup:
Signal
Generator
R&S FSW
Signal generator settings (e.g. R&S SMU):
Frequency:
850 MHz
Level:
0 dBm
Modulation:
CDMA2000
Procedure:
1. Preset the R&S
FSW.
2. Set the center frequency to
850 MHz
.
3. Set the span to
4 MHz
.
4. Set the reference level to
+10 dBm
.
5. Select the "Channel Power ACLR" measurement function from the "Select Mea-
surement" dialog box.
6. Set the "CDMA2000 1X" standard for adjacent channel power measurement in the
"ACLR Setup" dialog box.
The R&S
FSW sets the channel configuration according to the 2000 standard with
2 adjacent channels above and 2 below the transmit channel. The spectrum is dis-
played in the upper part of the screen, the numeric values of the results and the
channel configuration in the lower part of the screen. The various channels are rep-
resented by vertical lines on the graph.
The frequency span, resolution bandwidth, video bandwidth and detector are
selected automatically to give correct results. To obtain stable results – especially
in the adjacent channels (30 kHz bandwidth) which are narrow in comparison with
the transmission channel bandwidth (1.23 MHz) – the RMS detector is used.
7. Set the optimal reference level and RF attenuation for the applied signal level using
the "Auto Level" function in the AUTO SET menu.
8. Activate "Fast ACLR" mode in the "ACLR Setup" dialog box to increase the repeat-
ability of results.
The R&S
FSW sets the optimal RF attenuation and the reference level based on
the transmission channel power to obtain the maximum dynamic range. The
shows the result of the measurement.
Channel Power and Adjacent-Channel Power (ACLR) Measurement
