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NAVMAN
GPS 4100
WHAT IS GPS?
The Global Positioning System (GPS) is a network of satellites launched by the US military in the 1970s. The satellites
continuously transmit accurate time and position information, which is freely used by commercial and military applications
worldwide. GPS receivers such as the GPS 4100 are designed to pick up the high frequency radio signals from these
satellites, and use the information to determine your exact location. Today, there are many applications that use GPS, from
marine to automotive, aviation and military.
There are 24 satellites in total, orbiting approximately 12,000 miles above the earth. While a GPS receiver can detect
signals from up to 12 satellites at any one time, only three are needed to provide the two-dimensional position or “
fi
x”
(latitude and longitude) that is required for vehicle navigation systems. A three dimensional
fi
x requires four satellites and
provides improved positional accuracy.
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BLUETOOTH and the GPS 4100
Bluetooth is a personal wireless radio link, used to enable devices to communicate without a physical cable. Bluetooth is
fast, economical and uses very little power.
Many laptops and PDA's can use the Bluetooth link, and can communicate with Bluetooth-enabled devices such as
mobile phones and, of course, the Bluetooth GPS Receiver which is an integral part of this GPS 4100 solution.
The Bluetooth GPS Receiver contains a GPS antenna to receive GPS signals from the sky, an internal microcomputer to
calculate the position of the receiver on the earth, and a Bluetooth link to send the GPS position to the laptop or Pocket
PC. The Bluetooth GPS Receiver can communicate with a PDA within a radius of at least 10 m (33 ft).
Typically, the Bluetooth GPS Receiver is mounted on your vehicle dash or on the back window, in a position where the
receiver has a clear view of the sky and can receive the GPS signals easily. The receiver then sends the GPS position
information to your PDA, which is used by your third party software
to plot your position on a map and direct you to
your destination. Because the GPS receiver is wireless, you can simply leave the PDA in your pocket and let the voice
instructions guide you, or mount it somewhere on the dash so that you can view the street maps as you travel.
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