Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Getting Started
Measurements on Modulated Signals
2.34 Operating Manual 1164.4556.12 - 06
2.5.3.2 Measurement Example 2 – Measuring the adjacent channel power of an IS136
TDMA signal
Test setup:
Settings on the signal generator (e.g. R&S SMIQ):
Measurement with the R&S FSP
1. Set the R&S FSP to its default state.
➢
Press the PRESET key.
The R&S FSP is in its default state.
2. Set up the R&S FSP for synchronization to an external reference frequency.
➢
Press the SETUP key.
➢
Set the REFERENCE softkey to EXT .
3. Set the center frequency to 850 MHz-
Press the FREQ key and enter 850 MHz .
4. Configure adjacent channel power measurement for IS136 signals.
➢
Press the MEAS key.
➢
Press the CHAN PWR ACP ! softkey.
➢
Press the CP/ACP STANDARD softkey.
➢
Select NADC IS136 from the list of standards and press ENTER .
The R&S FSP performs the power measurement in 5 channels (in the useful
channel and in the two upper and two lower adjacent channels).
Signal
generator
FSP
Ext Ref IN
Ext Ref Out
RF Inp
As the modulation spectrum of the IS136 signal leaks into the adjacent channel, it
makes a contribution to the power in the adjacent channel. Exact tuning of the
R&S FSP to the transmit frequency is therefore critical. If tuning is not precise,
the adjacent channel power ratios in the lower and upper adjacent channels
become asymmetrical. The R&S FSP’s frequency and the generator frequency
are therefore synchronized.
Frequency: 850 MHz
Level: -20 dBm
Modulation: IS136/NADC