Video filter, Figure 2 video filter settings, 300 khz signal – Bird Technologies 5019D-Manual User Manual
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Video Filter
Figure
2
Video Filter Settings, 300 kHz Signal
Except for average power and VSWR measurements, all WPS
measurements rely on a variable video filter to improve accu-
racy. This filter can be set to either 4.5
kHz, 400 kHz, or full
bandwidth. It should be as narrow as possible while still being
larger than the demodulated signal bandwidth (video band-
width). Narrowing the filter limits the noise contribution
caused by interfering signals. Listed below are some common
modulation schemes and the appropriate video filter.
Video Filter
Modulation Type
4.5 kHz
CW Burst (Burst width > 150 μs), Voice Band
AM, FM, Phase Modulation, Tetra
400 kHz
CW Burst (b.w. > 3 μs), GSM, 50 kHz AM,
DQPSK
Full
Bandwidth
CW Burst (b.w. > 200 ns), CDMA, WCDMA,
DQPSK, DAB/DVB-T