Smiths Kelvin Hughes Nucleus 3 5000 Series, Системный справочник

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VIDEO COR RE LA TION AND IN TER FER ENCE
RE JEC TION
187 Signal correlation is used to reduce radar interference
(interference rejection) and to reduce clutter (scan to
scan correlation).
In ter fer ence Re jec tion (IR)
188 Consecutive transmissions are compared and only
signals present on
both transmissions are painted.
Interference from other radars is suppressed and receiver
noise reduced.
Scan to Scan Cor re la tion (SC/SC)
189 Signal correlation reduces random clutter returns and
preserves radar signals that correlate (are present) for
two successive scans of the antenna. Targets that do not
paint consistently are displayed at the medium echo if one
scan is missed, at the weak echo colour if two scans are
missed and not at all if more than two scans are missed.
Interference rejection, and receiver noise reduction are also
used to further improve the radar image.
190
A target that stays in the same position, or overlaps on
two consecutive scans correlates (Target A). A target
with high relative speed on a low range scale that does not
overlap on two consecutive scans paints at a lower intensity
level (Target B). A longer pulse length improves correlation,
but close targets moving at a high tangential speed may still
not correlate.
VIDEO EN HANCE
191 Enhances the radar signals by stretching the size of
strong radar returns. Clutter should be reduced to a
minimum before switching to ENH.
July 03 1.26 Amdt. 5
KH 2020
Chap 1
CD-1977
Interference
A
TARGET
B
TARGET
CD-1976
CD-1975
Video Enhance
CD-1974
Video Normal