Rohde & Schwarz R&S SMU200A, Service Manual

Page: 85 / 294

R&S SMU200A Test Procedures
1007.9845.82 1.59
E-12
Image Rejection over the Complete Unit
The equipment layout for generating multicarrier signals includes the options R&S B13 (baseband main
module), R&S B10 (baseband generator) and R&S K61 (multicarrier CW).
Test equipment Signal analyzer R&S FSQ (table 1-1, pos. 24).
Test setup
Connect the signal analyzer to the RF output of the DUT.
Test method
A single sideband signal is generated using the Multicarrier CW
functionality by selecting only one carrier. The offset is set with the
Frequency Offset function in the Baseband menu. The image rejection is
the difference between the shifted signal and its mirror on the opposite
side of the center frequency.
Measurement Settings on DUT
RF On
Frequency: 1 GHz
Level: 0 dBm
Multi Carrier CW: State On
Number of Carriers: 1
Frequency Offset:
10 kHz, 10 MHz to 40 MHz in 10 MHz steps,
-10 kHz, -10 MHz to -40 MHz in -10 MHz steps
Settings on analyzer
FREQ CENTER 1 GHz
SPAN = 3 x offset frequency
BW COUPLING RATIO SPAN / RBW MANUAL 300
AMPT/REF LEVEL 5 dBm
MKR /MARKER 1 set to peak
In the displayed spectrum, use MARKER DELTA to measure the
image rejection.
The number of necessary measurement depends on the number of installed RF- and baseband paths, see
following table:
Installed paths 1 x RF
1 x BB 2 x RF
2 x BB 2 x RF
1 x BB 1 x RF
2 x BB
Image sideband suppression
Number of measurements
1 x 2 x 2 x 1 x