Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Getting Started
Measuring the Spectra of Complex Signals
2.4 Operating Manual 1164.4556.12 - 06
With an intermodulation distance of 60 dB and an input level, Pw, of –20 dBm, the
following 3
rd order intercept is obtained:
TOI = 60 dBm / 2 + (-20 dBm) = 10 dBm.
2.2.2 Measurement Example – Measuring the R&S FSP’s intrinsic
intermodulation distance
To measure the intrinsic intermodulation distance, use the following test setup.
Test setup:
Settings on the signal generator (e.g. R&S SMIQ):
Measurement using the R&S FSP:
1. Set the R&S FSP to its default settings.
➢
Press the PRESET key.
The R&S FSP is in its default state.
2. Set center frequency to 1 GHz and the frequency span to 1 MHz.
➢
Press the FREQ key and enter 1 GHz.
➢
Press the SPAN key and enter 1 MHz.
3. Set the reference level to –10 dBm and RF attenuation to 0 dB.
➢
Press the AMPT key and enter -10 dBm .
➢
Press the RF ATTEN MANUAL softkey and enter 0 dB.
By reducing the RF attenuation to 0 dB, the level to the R&S FSP input mixer
is increased. Therefore, 3
rd order intermodulation products are displayed.
4. Set the resolution bandwidth to 10 kHz.
➢
Press the BW key.
Level Frequency
Signal generator 1 -10 dBm 999.9 MHz
Signal generator 2 -10 dBm 1000.1 MHz
Signal
Generator 1
Signal
Generator 2
Coupler R&S FSP