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5.7.5.1 Off-route sensitivity and Recalculation delay
Depending on the quality of your GPS device, the GPS antenna location in the car
and the environment you are driving in, route recalculation can behave differently.
Uniden Navigation may think you have departed the proposed route and perform a
recalculation even if you have not done so.
When the GPS reception is poor (e.g. driving in an urban environment with a
low sensitivity GPS), occasional wandering (called position uctuation) of the
calculated GPS position is likely. Although Uniden Navigation employs a
sophisticated Lock-on-Road system that will mostly suppress these position errors by
aligning your position to the recommended route and the road network of the map,
sometimes the errors are too large to correct.
To reduce the effect of large errors, you can increase the recalculation tolerance two ways.
Off-route sensitivity
This is a range of relative values from 0 to 10, telling Uniden Navigation how far the
GPS position should be from the recommended route before the program decides
to recalculate. Lower values make Uniden Navigation insensitive to position errors;
higher values will result in quicker reactions.
Recalculation delay
This is a setting that helps suppress the effects of position uctuation. With a few
seconds delay in recalculation even large position jumps can be survived without a
need for route recalculation.
5.7.5.2 U-turn penalty
You can ne-tune the way Uniden Navigation takes U-turns into account when
planning a route. You can tell Uniden Navigation how much extra distance you would
travel to avoid a U-turn.
Note: This value is taken into account only if U-turns are enabled in Route
Parameters (Page 62).
5.7.5.3 Cross-border planning
By default Uniden Navigation plans routes using the border crossing points.
However, if you live near the border, you can disable border crossing with this switch
to remain within one country.
5.7.5.4 Keep position on road (Lock-on-Road)
Uniden Navigation is normally used for vehicle navigation, therefore Lock-on-Road
will display the position arrow precisely over roads, seamlessly correcting small GPS
errors. For pedestrian use you may consider disabling Lock-on-Road to make Uniden
Navigation always show your exact position.