Video Bandwidth - Agilent Technologies FieldFox N9913A User Manual

Resolution Bandwidth (Res BW)
In SA Mode, the Res BW provides the ability to resolve, or see closely spaced
signals. The narrower (lower) the Res BW, the better the spectrum analyzer can
resolve signals. In addition, as the Res BW is narrowed, less noise is measured by
the spectrum analyzer ADC and the noise floor on the display lowers as a result.
This allows low level signals to be seen and measured. However, as the Res BW is
narrowed, the sweep speed becomes slower.
How to set Res BW

 Then
 Then choose from the following:
The current Res BW setting is shown at the bottom of the screen.
#Res BW x.xx XHz ( # ) means manual setting.
This setting could impact the accuracy of the measurement. See Specifications on
page 194.
NOTE The Res BW setting also affects the Sweep Type setting. Learn how on page 91
Video Bandwidth (Video BW)
Video BW is a smoothing operation that is performed after measurement data is
acquired. The trace data is effectively smoothed so that the average power level
of the displayed noise is the same, but the peaks and valleys of adjacent data
points are smoothed together. More smoothing occurs as the Video BW is set
lower. However, as the Video BW is narrowed, the sweep speed becomes slower.
How to set VBW

 Then
 Then choose from the following:.
NOTE To change this setting from Man to Auto, press Video BW twice.
The current Video BW setting is shown at the bottom of the screen.
# VBW x.xx XHz ( # ) means manual setting.
When the Res BW/Video BW ratio exceeds 10,000, a
appear to indicate that the Video BW filter has reached the maximum capacity
for averaging.
90
Press BW 2.
Res BW
Auto
Res BW is coupled to the frequency span. As the frequency span is
o
narrowed, the Res BW is also narrowed providing increased ability to
resolve signals.
To change this setting from Man to Auto, press Res BW twice.
Man Enter a Res BW value using the numeric keypad, the ▲|▼ arrows, or
o
the rotary knob. Then press a multiplier if necessary or press Enter .
Press BW 2.
Video BW
Auto
Couples Video BW to the ResBW in a 1-to-1 ratio.
o
Man Enter a Video BW value using the numeric keypad, the ▲|▼ arrows,
o
or the rotary knob. Then press a multiplier if necessary or press Enter.
Meas UNCAL
warning may
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