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Measurements
R&S
®
FSW
153
User Manual 1173.9411.02 ─ 19
Noise cancellation
The results can be corrected by the instrument's inherent noise, which increases the
dynamic range.
In this case, a reference measurement of the instrument's inherent noise is carried out.
The measured noise power is then subtracted from the power in the channel that is
being analyzed (first active trace only).
The inherent noise of the instrument depends on the selected center frequency, resolu-
tion bandwidth and level setting. Therefore, the correction function is disabled when-
ever one of these parameters is changed. A disable message is displayed on the
screen. To enable the correction function after changing one of these settings, activate
it again. A new reference measurement is carried out.
Noise cancellation is also available in zero span.
Currently, noise cancellation is only available for the following trace detectors (see
●
RMS
●
Average
●
Sample
●
Positive Peak
Remote command:
Fast ACLR
If activated, instead of using the IBW method, the R&S
FSW sets the center frequency
to the different channel center frequencies consecutively and measures the power with
the selected measurement time (= sweep time/number of channels).
Remote command:
Selected Trace
The CP/ACLR measurement can be performed on any active trace.
Remote command:
Absolute and Relative Values (ACLR Mode)
The powers of the adjacent channels are output in dBm or dBm/Hz (absolute values),
or in dBc, relative to the specified reference Tx channel.
"Abs"
The absolute power in the adjacent channels is displayed in the unit
of the y-axis, e.g. in dBm, dBµV.
"Rel"
The level of the adjacent channels is displayed relative to the level of
the transmission channel in dBc.
Remote command:
Channel Power and Adjacent-Channel Power (ACLR) Measurement