Anritsu MS8608A, Operation Manual, Page: 135 / 338

6-23
Section 6 Performance Tests
Actual filter envelop
Sideband
noise
Sideband phase noise
When the resolution bandwidth is set to a fixed value and a signal that has far less sideband-noise level than the
equipment to be tested is input, check the level of the noise as compared to the peak signal (dBc) at the
specified frequency away from the peak.
Since the average value is measured for noise level, use a
video filter for measurement.
This sideband noise is a spectrum response which is
modulated by the internal noise of the spectrum analyzer. If
this response is large, the actual filter envelope is masked by
the noise as shown, which makes measurement impossible.
(1) Specification
• Sideband noise:
≤
–108 dBc/Hz (Frequency: 1 GHz, 10 kHz offset)
≤
–120 dBc/Hz (Frequency: 1 GHz, 100 kHz offset)
(2) Test instrument
• Signal generator: MG3633A Synthesized Signal Generator
(3) Setup
10MHz STD
Buff Out
REF IN
Synthesized signal
generator
MG3633A
SG
RF OUTPUT
RF Input
Coaxial cable
(BNC connector)
Coaxial cable
(N-type connector)
Sideband Noise Test