Rohde & Schwarz SML01, Руководство по эксплуатации

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Test sequence R&S®SML / R&S®SMV03
1147.7621.12 10.44 E-6
Vector modulation
Input impedance (VSWR)
Test equipment Test setup for output reflection factor
(
Performance test R&S SML03 /
R&S SMV03)
Test setup The test port of the bridge is connected to the I or Q input instead
of the RF output.
Measurement Settings on R&S SMV03
Level 0 dBm.
Carrier frequency 900 MHz.
Vector modulation on .
Settings on signal generator
Level 10 dBm.
Carrier frequency 5, 10 and 30 MHz.
Screw the VSWR bridge off and measure the level as reference
level.
Connect the test port of the VSWR bridge to I input and measure
the level again.
The voltage ratio of test level to reference level is the input
reflection coefficient r of the I input.
From this, the voltage standing wave ratio (VSWR) can be
calculated as follows:
VSWR = (1+r)/(1-r)
Repeat the measurement for the Q input.
Maximum level
Test equipment Power meter (Table 5-1, item 8).
DC voltage source (Table 5-1, item 12).
Test setup Connect the power meter (Table 5-1, item 8) to the RF output.
Connect DC voltage source to the I or Q input.
Measurement Settings on R&S SMV03
Level 0 dBm.
Carrier frequency 900 MHz.
Measure level without modulation as reference level.
SelectSTATE IQ in the menu Vector Mod. Set DC voltage source
to 0.500 V. Measure the level again .
The diffrence between the levels should be within permissible
tolerance specified in the data sheet.