Simrad GO XSE Series, Operator'S Manual

Page: 121 / 242

Possible target tracking errors
Some factors can generate tracking errors or make the radar image
difficult to read, and therefore reduce target detection capability:
• Sea, rain, snow and low clouds returns
• Radar Interference
• Sidelobe echoes
• Blind sectors
• Low signal to noise ratio and signal to clutter ratio
Warning:
The speed and course of a radar target are
obtained by consecutive measurements of the echo
position. The data is then filtered to reach the required
precision. This means, that every abrupt change of
speed and direction will be recognized with a certain
delay to reach absolute certainty that the target is
moving in a different way. The confirmation delay is
about five scans and after that some additional time is
needed to reach the same data precision as from
before the maneuver.
Sea, rain, snow and low clouds returns
Radar echoes in sea, rain or weather clutter areas may be masked by
the clutter. The effects of such errors appear as continuous big
changes of the target course and speed vectors. Sometimes the
symbol of a target that has been acquired at high speed can slip
away from the real target position after a certain time, and this
might generate the lost target alarm.
These errors can be avoided or at least minimized by proper manual
adjustments of sea and rain controls, or by selecting the automatic
control option. For more details, see
"Adjusting the radar image"
on page
113.
Radar interference
Other radars operating in the same frequency band can generate
interference. Normally this is seen on the radar screen as a series of
spirals. When the interference falls on the tracked target, it can
cause a deformation of the size of the echo, and consequently a
small error in the target's course and speed values.
Radar | GO XSE/XSR Operator Manual
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