Application Example: GSM AM Suppression Test
R&S
®
SMW-K550
17
User Manual 1178.3263.02 ─ 01
The four wanted signals are routed to the RF A; the interfering signal to RF B.
3. In the status bar, set the frequency ("Freq A" and "Freq B") to the frequency of the
interfering signal (f
i
).
The wanted signals are shifted and arranged in pairs symmetrically around the
interferer.
4. In the status bar, set the level values as follows:
● Level A is the sum power level of the 4 wanted signals. The required values are
listed in
TS 51.021
, table 7.8-1.
● Level B is the signal level of the interfering signal, as listed in
TS 51.021
, table
7.8-2.
In this example, the power levels of the wanted signals are -94 dBm and -98 dBm.
The interfering signal level is -31 dBm.
5. In the baseband domain, signals are leveled relative to each other. We assume,
that the -98
dBm signals are generated in "Baseband A".
To boost the signals generated in "Baseband B", select "Baseband B > Baseband
Offsets > Baseband B >
Gain =
4
dB".
How to configure the GSM baseband signal
The following is a list with
general steps
for configuring the interfering signal. The
interfering signal is GMSK modulated PN9 sequence signal.
Configure the wanted signals in the same way. Consider the coding requirements
specified in the
TS 51.021
.
How to Generate Signals for GSM AM Suppression Tests
