Koden MDC-5004, Инструкции по эксплуатации

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Chapter 2 Radar Basic Operation MDC-5000 Series
0093153004-00 2-10
2.8 Reject rain/snow clutter (anti-RAIN)
In rain or snow, targets become hard to be seen as a result of
unwanted weather reflection.
Rain or snow image appears as a large target echo with
surrounding mid gradation rim.
Anti-RAIN is available MAN and CFAR.
Adjustment of MAN (manual) and CFAR (Constant False Alarm
Rate) by turning RAIN knob suppresses clutter, and helps to see
targets clearly.
MAN is effective for suppression of rain and snow.
CFAR is effective for suppression of sea, rain and snow clutter.
[RAIN MODE] can be changed directly in the upper right of the display without using menu function.
Note:
• Small target becomes harder to detect when [RAIN] is used together with [SEA]. Therefore, please
adjust them carefully.
• The echo process (refer to 2.22 Echo process) is useful to reject rain clutter. Be careful, when the
echo process is active, high-speed targets are harder to detect than stationary ones.
• The performance of radar detection range is degraded by rain as shown in the figure below.
The details of the figure (An example of 6 NM range)
A target which was able to observe at 6 NM (Original range of first detection), can only be detected at
the range (Reduced Range of First Detection) shown below in rain condition.
4 mm/h rain (short pulse): approx. 5.6 NM 4 mm/h rain (long pulse): approx. 1.5 NM
16 mm/h rain (short pulse): approx. 3.9 NM 16 mm/h rain (long pulse): approx. 0.5 NM
Rain clutter
4 mm/h rain
(short pulse)
4 mm/h rain
(long pulse)
16 mm/h rain
(short pulse)
16 mm/h rain
(long pulse)