Venturer HPS9308 GPS Receiver User Manual


 
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7.6.4 Route Options
You can set the basic route
parameters on the Route
Parameter settings screen
described in (7.4). On this
screen you have more ways
to inuence route planning and
route recalculation.
7.6.4.1 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. This
navigator 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 amongst many
tall buildings), occasional
wandering (called position
uctuation) of the calculated
GPS position is likely. Although
this Navigator employs a
sophisticated Follow-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
this Navigator how far the
GPS position should be
from the recommended
route before the program
decides to recalculate. Lower
values make this Navigator
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 tolerated without a need
for route recalculation.