Non-Hysteresis - JRC JMA-5204 Instruction Manual

5.4.8 Non-Hysteresis

Set a non-hysteresis level at which targets that were once identified as one target by the association assessment
function are identified as separate targets.
Set the condition for separating an association symbol into a tracked target symbol and an AIS target symbol.
Procedure 1
2
Press the [TT menu] key.
Press the following buttons.
3 Target setting
1 Association assessment setting
8 Non-Hysteresis
Set a level of non-hysteresis at which an associated target is separated into individual
targets between 0% and 300%. The standard percentage is 100%.
In the case of 100%, The level of non-hysteresis is equal to n/m.
n: The time of judgment which an associated target is separated into individual targets
m: The time of judgment
Therefore 50% means that the level of hysteresis is equal to n/(2*m).
200% means that the level of hysteresis is equal to (2*n)/m.
A larger value means a stricter condition.
It becomes harder to separate a tracked target symbol from an AIS target symbol.
Targets that are not separated to start with are less likely to be separated, and also,
separated individual symbols are less likely to be displayed properly after separation.
A smaller value means a looser condition.
It becomes easier to separate a tracked target symbol from an AIS target symbol.
Targets that are not separated to start with are more likely to be separated, and also,
separated individual symbols are more likely to be displayed soon after separation.
Adjust the setting in accordance with the intention.
Caution
When a small value is set as a hysteresis
condition, a tracked target near an AIS target is
identified as the AIS target and may thus
disappear from the display.
For example, when a pilot vessel equipped with
the AIS function (a small target which is not a
tracked target) goes near a cargo vessel which
is a tracked target without the AIS function, the
tracked target symbol for the cargo vessel may
disappear.
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