Eclipse - Fujitsu Ten AVN5435 GPS Receiver User Manual


 
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Helpful tips
3. Accuracy and error
Positioning accuracy
The GPS is a very accurate satellite controlled by the U.S. Department of Defense. Errors
may result due to the occurrence of a multipath caused by reflections off buildings or other
structures.
GPS signal quality and reception conditions
Any obstruction coming between the satellite and the GPS antenna will disrupt signal
reception from the satellite.
Also, 3 or more signals must be received simultaneously to enable positioning. When driving
along locations such as those shown below, GPS positioning is not possible.
In addition, obstructions placed on or near the GPS antenna (such as a load) will disrupt
signals from the satellite.
Underground, in a tunnel or
in an indoor parking structure
Surrounded by obstructions
such as tall buildings In a building
Densely wooded areas Under an elevated road On a cliff side road or
at a cavern opening
•Because the GPS satellite orbits the earth, signal reception conditions may vary
depending on the position of the satellite even if driving in the same area. Signals from a
satellite orbiting near the horizon are more likely to be obstructed.
•The GPS satellite is controlled by the U.S. Department of Defense and can be
deliberately made to lose positioning accuracy.