Section 6 Target Tracking and AIS 6-2
6.1 Restrictions
The acquisition and Target Tracking functions have the following restrictions.
Depending on 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,
there is a possibility of swapping them or losing one of them. Such swapping or less of targets may
also occur if the target being tracked is affected by rain/snow clutter or sea clutter or moves very close
to land.
The intensity of echoes and the Target Tracking function have a correlationship, and thus the target will
be lost if no echoes are detected during six scans in succession.
If such 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 or other noise may be erroneously
detected and tracked as a target, and resultingly, a false alarm may be issued.
To execute accurate tracking, it becomes necessary first to appropriately adjust the gain, sea clutter
suppression, rain/snow clutter suppression and tune of the radar so that the target to be acquired and
tracked is clearly displayed on the radar display.
Inappropriate settings of these adjustments reduce the reliability/accuracy of automatic target tracking.