Raymarine A65, Руководство по эксплуатации

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Interference
When two or more radar-equipped vessels are
operating within range of each other mutual radar
interference can occur. This usually appears as a
spiral of small dots from the display centre This type
of interference is most noticeable at long ranges.
This interference can be suppressed using the
interference rejection settings. The images in the
table below show how the Interference rejection
settings can clear up some of this interference:
Interfer-
ence re-
jection
off
Interfer-
ence re-
jection
on
Maximum radar range
The usable range of the radar is limited by factors
such as the height of the scanner, and height of the
target.
Maximum radar range is essentially line-of-sight, so
is limited by the height of the scanner and the height
of the target as illustrated below:
a
1
a
2
h
H
D1643-4
Rmax
Rmax = 2.23 ( h + H )
1
3
2
Item Description
1 Radar equipped vessel.
2 Curvature of the earth.
3 Target (Cliff).
a
1
Radar horizon of antenna.
a
2
Radar horizon of target.
R
max
Maximum radar range in
nautical miles.
R
max
= a
1
+ a
2
h Radar antenna height in
metres.
H Target height in metres.
The table below shows typical maximum radar
ranges for various radar antenna heights and target
heights. Remember that although the radar horizon
is greater than the optical horizon, the radar can only
detect targets if a large enough target is above the
radar horizon.
Antenna height
(meters) Target height
(meters) Maximum range
(Nautical miles)
3 3 7.7
3 10 10.9
5
3 8.8
5 10 12
Radar application
241