Glossary - Uniden iGO50 Owner's Manual

6 Glossary

2D/3D GPS reception
The GPS receiver uses satellite signals to calculate its (your) position and needs
at least four signals to give a three-dimensional position, including elevation.
Because the satellites are moving and because objects can block the signals, your
GPS device might not receive four signals. If three satellites are available, the
receiver can calculate the horizontal GPS position but the accuracy is lower and
the GPS device does not give you elevation data: only 2D reception is possible.
Active route
The currently navigated route. Whenever the destination is set, the route is active
until you delete it, reach your destination or you quit the software. See also: Route.
City Centre
The city/town centre is not the geometric centre of the settlement but an arbitrary
point the map creators have chosen. In towns and villages, it is usually the most
important intersection; in larger cities, it is one of the important intersections.
Colour theme
Your software comes with different colour themes for daytime or night use of the
map and menu screens. Themes are custom graphic settings and they can have
different colours for streets, blocks or surface waters in 2D and 3D modes, and
they display shades or shadows in different ways in 3D mode.
One daytime scheme and one night scheme is always selected for the map and for
the menus. The software uses them when it switches from day to night and back.
GPS accuracy
Several factors have impact on the deviation between your real position and the
one given by the GPS device. For example, signal delay in the ionosphere or
reflecting objects near the GPS device have a different and varying impact on how
accurately the GPS device can calculate your position.
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