Rohde & Schwarz R&S SMU200A, Service Manual

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Test Procedures R&S SMU200A
1007.9845.82 1.54
E-12
Differential I/Q Output (Option R&S B16)
Important:
Before the measurement, Signal Analyzer R&S FSQ must be calibrated as follows by means of a reference
measurement at the measurement frequency in question:
1. Connect the RF output of the DUT to the power meter and measure the output level.
2. Include the measured level as a reference value/calibration value in the R&S FSQ.
Differential signal balance
Test equipment Signal analyzer R&S FSQ (table 1-1, pos. 24).
Test setup
Connect the signal analyzer to the I-, Q-, I Bar- and Q Bar-output of
the DUT.
Test method A single sideband signal is generated using the Custom Digital
Modulation functionality by selecting only one carrier (DC-Signal). The
offset is set with the Frequency Offset function in the Baseband menu.
The test frequencies are set one after the other. The differential signal
balance is obtained from the level differences between I and I Bar or Q
and Q Bar at a particular frequency.
Measurement Settings on DUT
Custom Digital Modulation: State ON
Data Source: All 0
Modulation Type: BPSK
Filter: Rectangular
Frequency Offset: measurement frequency
I/Q Out Menu:
Output Type:
Differential
Mode: Normal
Settings on analyzer
FREQ CENTER 1 MHz
SPAN 0 Hz
AMPT/REF LEVEL + 10 dBm
BW /RES BW MANUAL 30 kHz
Measurement frequencies: 1MHz, 10 MHz, 30 MHz and 40 MHz.