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General description of what GPS is and how it works
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GPS (Global Positioning System) is the only system today able to show you your exact position on the Earth anytime, in any weather,
anywhere. GPS satellites, 24 in all, orbit at 11,000 nautical miles above the Earth. They are continuously monitored by ground
stations located worldwide. The satellites transmit signals that can be detected by anyone with a GPS receiver. Using the receiver,
you can determine your location with great precision.
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The satellites are positioned so that we can receive signals from six of them nearly 100 percent of the time at any point on Earth. You
need that many signals to get the best position information. Satellites are equipped with very precise clocks that keep accurate time to
within three nanoseconds- that's 0.000000003, or three billionths of a second. This precision timing is important because the receiver
must determine exactly how long it take s for signals to travel from each GPS satellite. The receiver uses this information to calculate
its position.
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Although GPS was designed for military use, many thousands of civil jams make use of it. The satellites actually broadcast two
signals, one is only formilitary use, and one can be used by both military and civilians. Since GPS is passive (you only need to receive
the signal), there are no restrictions on who can use the signal available to civilians.
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GPS technology can be used in variety of fields besides providing navigation for vehicles on the sea, in the air and on the ground.
GPS applications also include keeping track of where a fleet of trucks, trains, ships or planes are and how fast they are moving;
direction emergency vehicles to the scene of an accident; mapping where a city's assets are located ; and providing precise timing for
endeavors that require large-scale coordination
Caution
Read before you start to use:
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Global position system (GPS) is obtained by American Ministry of National Defense, and they got the full responsibility about the
preciseness and the maintenance. Any changes may cause the capacity and preciseness of GPS differed.
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If you use this device inside of buildings, tunnels, or any huge objects beside you, the GPS signals might be cut-off or disturbed.
Please do not consider that the receiver is malfunction.
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The receiver operating temperature is located between
– 20°C and + 60°C. For safety and lifetime of Li-polymer battery usage, do not
place this device over two hours with overheated environment...