Agilent Technologies PSA Series Manual page 250

Front-Panel Key and SCPI Command Reference
Measurement keys
4.4.9.2 Meas Setup
Displays the measurement setup menu for the Modulation SINAD Measurement when the Modulation SINAD
key has been selected in the
Measurement
4.4.9.2.1 IF BW
Used to specify the IF BW, if the IF BW Type is set to Man.
Key Path:
Remote Command:
Preset:
State Saved:
Min:
Max:
Example:
4.4.9.2.2 IF BW Type
Used to adjust the IF Bandwidth that the analyzer uses while making a modulation measurement. In this
measurement, there are three BW types: Auto, Manual and Minimal. However, the parameter can be set only
when Bandwidth Type is set to Manual. In Auto and Minimal types, the system determines this parameter
automatically. Usually auto mode is sufficient for most measurement conditions, but this parameter allows
adjustment when challenging measurement conditions exist. Signals with hard to measure bandwidths, such as
low rate and high deviation FM/PM signals are an example. A value that is very close to the actual signal
bandwidth should be used in this case. (If the value is too low, an inaccurate measurement reading will result,
whereas a value too high will allow unwanted noise and increase measurement time, unnecessarily.) The type of
IF bandwidths that the PSA uses can vary from ~25 kHz to 8 MHz.
Auto: This is the default setting. This setting causes system to perform an occupied bandwidth measurement
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on the modulated signal. This measurement will occur at the start of any modulation measurement, and will
help determine the final IF bandwidth that the PSA will use in analyzing the signal. The main drawback of
this mode is measurement throughput; extra time is required during initialization to perform the bandwidth
measurement.
Manual: In this mode you can use the IF Bandwidth parameter to suggest a bandwidth for the system to use
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during demodulation. The actual IF bandwidth that is used will try to be greater than this value, and at a point
where the PSA is optimized to produce fast, accurate results. In this mode measurement throughput is
increased because initialization bandwidth measurements are bypassed. Another use of this mode is to ensure
that the analyzer is behaving correctly for signals whose bandwidth is hard to measure (that is, low rate audio
signals).
Minimal: This will choose the minimum IF bandwidth necessary to perform the modulation measurement.
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menu.
Measure
Meas Setup
[:SENSe]:MODSinad:BANDwidth|BWIDth <bandwidth>
[:SENSe]:MODSinad:BANDwidth|BWIDth?
1 MHz
Saved in instrument state.
1 kHz
10 MHZ
:MODSinad:BAND 200kHz
:MODSinad:BAND?
Chapter 4