Uniden GNS8430 GPS Receiver User Manual


 
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8 Glossary
The manual may contain many technical terms. Please look below for an explanation
if you are unfamiliar with some of them.
2D/3D GPS reception: The GPS receiver uses satellite signals to calculate its
(your) position. Depending on the current positions of the ever moving satellites
in the sky, and the objects in your environment, the signal that your GPS device
receives may be weaker or stronger. Your GPS needs strong signal from at least four
satellites to give a three dimensional position including elevation. If fewer satellites are
available, it may still be possible to calculate the position but the accuracy will be
lower and the GPS device will not calculate elevation. This is called 2D reception.
Uniden Navigation shows the quality of reception on the Main menu (Page 15), the
GPS Data screen (Page 18) and both map screens (Page 33). Note that 2D and 3D
GPS receptions have nothing to do with the 2D and 3D display modes of the map.
That is a way of representing the map on the screen independently from the GPS
reception.
Accuracy: The difference between your real position and the one given by
the GPS device is affected by several different factors. The GPS is capable of
providing a guess of its current error based on the number of satellites it can receive a
signal from, and their position in the sky. This information is shown in Uniden Navigation
on the GPS Data screen (Page 16). Lower numbers indicate better accuracy, where 1.0
is near-perfection. Use it as a general reference only. Note that several other factors
affect the real accuracy, some of which the GPS is incapable of estimating (e.g. signal
delay in the ionosphere, reecting objects near the GPS device, etc.).
Active route: A route is an itinerary planned to reach your chosen destinations. A
route is active when it is used for navigation. Uniden Navigation has only one route
at a time, and it is always active until you delete it, reach the nal destination or exit
Uniden Navigation. When there is more than one destination to reach, the route is
cut into different legs (from one via point to another). Only one of these legs can be
active at one particular time. The rest of them are unused and shown in a different
colour on the map.
Automatic route planning (Autorouting): You only need to set up your destination,
and based on its map, the software will automatically gure out which roads you
need to take, and the turns you need to make to get there. Uniden Navigation will let
you select multiple destinations, and customise some important routing parameters
(Page 61).
Automatic route recalculation: If this function is enabled (Page 57), Uniden Navigation
recalculates your route if you deviate from it. When you miss a turn or avoid a
roadblock, Uniden Navigation waits for a few seconds to be sure you do not follow
the route any more (you can ne-tune it in Advanced settings), then recalculates the
route based upon your new position and heading.