8 Glossary
The Glossary will provide you with explanations for technical terms used throughout
this manual.
2D/3D GPS reception: The GPS receiver uses satellite signals to calculate
your current position. Depending on the current positions of the 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. AVIC-S2 shows
the quality of reception on the GPS Data screen (Page 23) and both map screens
(Page 29). 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 AVIC-S2 on the GPS
Data screen (Page 22). 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, reflecting 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. AVIC-S2 has only one route at a time,
and it is always active until you delete it, reach the final destination or exit AVIC-S2.
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 color on the map.
Automatic route planning (Autorouting): You only need to set up your destination,
and based on its map, the software will automatically figure out which roads you
need to take, and the turns you need to make to get there. AVIC-S2 will let you
select multiple destinations, and customize some important routing parameters
(Page 54).
Automatic route recalculation: AVIC-S2 recalculates your route if you deviate from
it. When you miss a turn or avoid a roadblock, AVIC-S2 waits for a few seconds to
be sure you do not follow the route any more, then recalculates the route based
upon your new position and heading.
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