Tektronix RSA6100A Series, Help Manual

Page: 187 / 415

RF Measurements > Phase Noise Frequency Tab
Setting Description
Measurement BW This sets the frequency range for the phase noise measurement range. The instrument’s
Frequency control is used to set the "carrier frequency of interest". The widest available
start/stop range is from 10 Hz greater than the carrier frequency (“Stop Offset”) to 1
GHz above the carrier (“Stop Offset”). Very small start offsets will take signi
fi cant time
to measure as very narrow resolution bandwidths are used in to achieve small-offset
measurements. Large-offset stop frequencies cause small effects on measurement time,
but will increase the displayed scale of the phase noise plot.
Start Offset Sets the starting point for the Phase Noise plot. Offset is from the carrier frequency.
The minimum start offset is 10 Hz. The maximum start offset is 100 MHz. The setting
is limited to powers of ten (1, 10, 100...).
Stop Offset Sets the stopping point for the Phase Noise plot. Offset is from the carrier frequency.
The minimum start offset is 100 Hz. The maximum stop offset is 1 GHz. The Stop offset
value must be at least 10X the Start offset value. The setting is limited to powers of
ten (1, 10, 100...).
Integration BW Integration bandwidth sets the frequency range over which integrated results for phase
noise (labeled “RMS Phase Noise”) and jitter are calculated. Integration start and stop
cannot exceed the measurement bandwidth. If you set the integration bandwidth
greater than the measurement, the error message ‘Setup error: Integration BW exceeds
Measurement BW’ will appear.
Start Offset Speci fi es the Integration BW’s start offset from the carrier frequency.
Stop Offset Speci fi es the Integration BW’s stop offset from the carrier frequency.
Track carrier frequency The instrument fi nds the carrier signal and measures its frequency at least once each
time the Phase Noise measurement is taken and reports the error between the Freq
setting and the measured frequency of the carrier. When Track carrier frequency is
enabled, the measurement adjusts its tuning to counteract the carrier error or drift. When
carrier tracking is disabled, the measurement is made using the Freq setting speci
fi ed by
the user.
Carrier threshold The minimum power level required for the signal to be recognized as a carrier. If no
signal is found above this level within 20 MHz of the Freq setting, the Phase Noise
measurement will fail.
xxx
RSA6100A Series Real-Time Spectrum Analyzers Help
175