Positioning
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Positioning
The Global Positioning System (GPS) is a worldwide radio
navigation system that includes 24 satellites and their
ground stations that monitor the operation of the
satellites. Your device has an internal GPS receiver.
A GPS terminal, such as the GPS receiver in your device,
receives low-power radio signals from the satellites, and
measures the travel time of the signals. From the travel
time, the GPS receiver can calculate its location to the
accuracy of meters.
The coordinates in the GPS are expressed in degrees and
decimal degrees format using the international WGS-84
coordinate system.
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.
GPS should only be used as a navigation aid. It should not
be used for precise location measurement and you should
never rely solely on location data from the GPS receiver for
positioning or navigation.
Your device also supports Assisted GPS (A-GPS).
Assisted GPS (A-GPS) uses a packet data connection to
retrieve assistance data to improve GPS performance. It
decreases the time to calculate the current location of
your device when your device is receiving signals from
satellites.
A-GPS is a network service.
Your device is preconfigured to use the Nokia A-GPS
service, if no service provider specific A-GPS settings are
available. The assistance data is retrieved from the Nokia
A-GPS service server only when needed.
You must have a packet data internet access point defined
in the device to retrieve assistance data from the Nokia A-
GPS service. To define an access point for A-GPS, press
,
and select
Tools
>
Settings
>
General
>
Positioning
>
Positioning server
>
Access point
. A WLAN access point
cannot be used for this service. The packet data internet
access point is asked when GPS is used for the first time in
your device.
