Operation Of Target Tracking And Ais; Preparation - JRC JMA-7133-SA Instruction Manual

JMA-7100 Instruction Manual
5.1

PREPARATION

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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.
This section explains the features of the target tracking and AIS functions, and the
initial setting for using each function.
Target Tracking Function
The target tracking function calculates the course and speed of a target by
automatically tracking the target's move.
The target tracking function enables the automatic acquisition of targets by using
the automatic acquisition zone function.
The target tracking function also enables the simulation of the ship maneuvering
method to avoid collisions by using the trial maneuver function.
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5.OPERATION OF TARGET TRACKING AND AIS

Attention
5－ 1
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5.1 PREPARATION
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