Operating Manual R&S SMIQ - Volume 1 - Rohde & Schwarz

SMIQTest Procedures5.3.23.2 Additional Modulation Frequency ResponseTest equipment, setup andmethod as aboveTesting Two frequency response measurements are made, the first onewith the fading simulator switched off and the second withbandwidth measurement setting. The additional frequency response is the difference between thefirst and second measurement.5.3.23.3 Carrier Leakage for FadingTest equipment Spectrum analyzer (table 5-1, item 2)Test setup Connect the spectrum analyzer to the RF output of the SMIQ. Terminate the I and the Q input with 50 Ω.Measurement Settings on the analyzer:Analyzer reference level to measurement level, span 10 kHz, RBW300 Hz, VBW 300 Hz. Settings on SMIQ- Measurement level -15 dBm- Measurement frequencies 400 MHz, 1 GHz, 2.2 GHz and 4.4 GHz First measure the unmodulated level as a reference. Settings on SMIQVector modulation ONFading: 1CH, PATH 1 ON, PROFILE PDOPP, FREQ RATIO 1.0 , DOPPFREQ 1.6 kHz, PATH LOSS 0 dB, other paths OFF, Now measure carrier leakage. The carrier leakage in dBc is the difference between the level of thespectral line at the carrier frequency and the reference level.5.3.23.4 Path AttenuationTest assemblyTest assembly with spectrum analyzer for fading simulationTest methodFor vector modulation, a single-sideband amplitude modulation(SSB-AM) is generated by applying a sinusoidal signal to the I inputand a cosine signal to the Q input. The second sideband and thecarrier are suppressed.Testing A dual-channel generator (pos. 18) is used to feed an I/Q signal tothe SMIQ via the I/Q inputs. Make sure the cables are of the samelength.1125.5555.03 5.65E-9