Glossary - Uniden TRAX4300 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.
Map
The software works with digital maps which are not simply the computerised versions of traditional
paper maps. Similarly to the paper road maps, the 2D mode of digital maps show you streets, roads,
and elevation is also shown by colours.
In 3D mode, you can see the altitude differences, for example valleys and mountains, elevated roads,
and in selected cities 3D landmarks and 3D buildings are also displayed.
You can use digital maps interactively: you can zoom in and out (increase or decrease the scale), you
can tilt them up and down, and rotate them left and right. In GPS-supported navigation, digital maps
facilitate route planning.
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