JRC JMA-5212-4, User Manual

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51
USAGE OF TARGET TRACKING FUNCTION
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There are the following limitations on use of the target
acquisition and target tracking functions.
[I]
Resolution between adjacent targets and swapping during
automatic target tracking
Depending on the particular distance and echo size, resolution between
adjacent targets during automatic target tracking usually ranges
somewhere between 0.03 to 0.05 NM. If multiple targets approach each
other, resolution will become about 0.05 NM and this may cause the
system to regard them as one target and thus to swap them or lose part
of them. Such swapping or less of targets may also occur if the picture
of the target being tracked is affected by rain/snow clutter returns or sea
clutter returns or moves very close to land.
[II]
Intensity of echoes and the target tracking function
The intensity of echoes and the tracking function have a correlationship,
and thus the target will be lost if no echoes are detected during six
scans in succession. If a lost target exists, therefore, radar gain must be
increased to support detection of the target. If, however, radar gain is
increased too significantly, sea clutter returns or other noise may be
erroneously detected and tracked as a target, and resultingly, a false
alarm may be issued.
[III]
Adverse effects of error sources on automatic tracking
To execute accurate tracking, it becomes necessary first to appropriately
adjust the [GAIN], [SEA] and [RAIN] dials of the radar so that the target
to be acquired and tracked id clearly displayed on the radar display.
Inappropriate settings of these adjustments reduce the reliability /
accuracy of automatic tracking.
Attention