Rohde & Schwarz FSP7 - Checking Modulation; Checking I;Q Modulation

Performance Test R&S FSP
1166.4556.82 1.24 E-1
Checking Modulation
Checking I/Q Modulation
Test equipment:
- Arbitrary waveform generator (refer to "Measurement Equipment",
item 16)
- Spectrum Analyzer (refer to "Measurement Equipment", item 15)
- 2 Voltmeters (refer to "Measurement Equipment", item 17)
- 2 BNC T pieces
Test setup with R&S ADS:  Apply the I and Q outputs of ADS to the I and Q inputs of the
analyzer. Check the ADS voltages in parallel via T pieces.
 Connect spectrum analyzer to the TG output.
Test setup with 33220A:  Apply the outputs of 33220A to the I and Q inputs of the analyzer.
Check the 33220A-
voltages in parallel via T pieces.
Synchronize the two 33220A via Option 001.
 Connect spectrum analyzer to the TG output.
Generator settings:
 Set DC voltage (offset) to 0 mV ± 3 mV
AC voltage: V(pp) = 1 V ± 10 mV
Frequency: 200 kHz
Phase (I/Q) = 90 degrees
Spectrum analyzer settings:
- [ FREQUENCY : 1 GHz ]
- [ SPAN : 1 MHz ]
- [ REF : REF LEVEL : 0 dBm ]
R&S FSP settings:
- [ FREQUENCY : 1 GHz ]
- [ SPAN : 0 MHz ]
- [ REF : REF LEVEL : 0 dBm ]
- [ NETWORK : SOURCE POWER 0 dBm ]
- [ MODULATION EXT I/Q ]
Measurement of residual
carrier:
 Switch off I and Q channels of the generator.
Voltmeter display: DC voltage < 3 mV
AC voltage < 3 mV
Set marker to peak:
- [ MKR  : PEAK ]
Read measured value on spectrum analyzer (marker peak).
Measurement of impairments
(imbalance of I and Q path
):
 Switch on I and Q channels of the generator.
Measure carrier amplitude at 1 GHz and lines at 1 GHz + 200 kHz
and 1 GHz – 200 kHz.