Vbw/Rbw - Agilent Technologies PSA Series User And Programming Manual

Instrument Functions: A - L
BW/Avg

2.3.3 VBW/RBW

Selects the ratio between the video and resolution bandwidths. Video bandwidth wider
than resolution bandwidth (VBW/RBW ratio > 1.000), provides the best peak
measurements of signals such as wideband radar pulses. VBW narrower than RBW
(VBW/RBW ratio < 1.000) reduces the variance of noise-like signals and makes spectral
components close to the noise floor easier to view. The knob and step keys change the ratio
in a 1, 3, 10 sequence. Pressing
1.000 X. When
VBW/RBW (Auto)
This key is grayed out when the Quasi Peak or EMI Average detector is
NOTE
selected.
Table 2-1 VBW/RBW Ratio Auto Rules
Detector Mode Noise
Marker
Peak On
Negative Peak On
Average On
Normal On
Sample On
Peak Off
Negative peak Off
Average Off
Normal Off
Sample Off
Key Path:
BW/Avg
Saved State: Saved in Instrument State
Factory Preset: Auto (1.0)
Range: 0.00001 to 3.0e6 (3,000,000)
72
or selecting
Preset Auto Couple
is selected, the ratio is determined as indicated below.
Ratio Notes
10 Noise response is esitmated for wide VBW case
10 Don't care
0.1 Narrow VBW for low-sigma marker readout
0.1 Don't care (noise marker makes is not valid with
normal detection.)
0.1 Narrow VBW for low-sigma marker readout
10 Wide VBW for good impulse BW (pulsed RF)
10 Don't care
0.1 Narrow VBW for low-sigma trace results
1.0 Swept analysis CW signal setting
1.0 Wide VBW for good impulse BW (pulsed RF)
, sets the ratio to
Auto All
Chapter 2