■ Global Positioning System (GPS)
The GPS is a worldwide satellite-based radio navigation system. The
internal GPS receiver can calculate the location of the device to an
accuracy of 10 metres. The accuracy depends, for example, on the
number of satellites, the signals of which the GPS module receives. In
optimal conditions, the accuracy may be within a few metres.
I n t r o d u c t i o n
The GPS antenna is located at the top of the navigation device. Some car
windscreens and windows may contain metal, that may block or weaken
the satellite signals.
If you stand still, GPS cannot detect which way you are facing because it
determines your direction on the basis of your movement.
Almost all digital cartography is inaccurate and incomplete to some
extent. Never rely solely on the cartography provided for use with the
The Global Positioning System (GPS) is operated by the government of the United
States, which is solely responsible for its accuracy and maintenance. The
accuracy of location data can be affected by adjustments to GPS satellites made
by the United States government and is subject to change with the United States
Department of Defense civil GPS policy and the Federal Radionavigation Plan.
Accuracy can also be affected by poor satellite geometry. Availability and quality
of GPS signals may be affected by your location, buildings, natural obstacles, and
weather conditions. The GPS receiver should only be used outdoors to allow
reception of GPS signals.
Any GPS should not be used for precise location measurement, and you should
never rely solely on location data from the GPS receiver and cellular radio
networks for positioning or navigation.