MapAsia.com Limited MapKing!G10
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5 GPS Positioning
IMPORTANT MESSAGE CONCERNING GPS TRACKING
The GPS tracking function of MapKing™ works on GPS satellite signals broadcasted for
civilian use. It is subject to inherent signal deviations and environmental interferences caused
by surroundings and bad weather. We cannot guarantee nor specify a precise level of accuracy
for the GPS positioning data displayed by MapKing™. It should also be noted that the Unites
States Department of Defence, who builds and operates the GPS system, is free to turn off or
down-grade the civilian signals of GPS during rare occasions like regional military conflict.
Although MapKing™ should work with most GPS receivers on NMEA0183 signal output format
regardless of their brand name or model; we cannot guarantee that MapKing™ integrates
flawlessly with ALL GPS receivers available in the market.
Please read the package for product information for product support GPS. In this chapter we
will discuss how to setup and operate the GPS functions, and the functions provides by
MapKing™ R12 with GPS.
5.1 About GPS
GPS (Global Positioning System) is developed and maintained by the US Defence Department.
The system was initially deployed for military use but was later open for civilian navigation. The
system comprises of more than 24 satellites on different orbits. The GPS receiver on the
ground picks up signals from at least three satellites and calculates its real time position by a
set of mathematical formulas generally known as ‘triangulation’.
GPS receivers must maintain line-of-sight with the satellites. GPS will not work indoor and its
accuracy tends to degrade significantly when the receiver is located under sheltered area or
near high-rise building structure or terrain.
5.2 GPS Startup
5.2.1 GPS Setup
GPS receiver needs to establish clear line of sight to receive signals from satellites orbiting in
the space. If the receiver is placed inside a vehicle or vessel, an extended antenna is normally
required to pick up signals beyond the enclosed area of the vehicle or vessel. Please note that
various types of I/O interface exist among different types of pocket PC (even for the same
brand), you should ensure that the output interface of the receiver is compatible with your
pocket PC. Consult the technical specifications or device dealer of your receiver or pocket PC if
you are in doubt about compatibility.
