Haicom HI-203E Use Manual - Is and How It Works.
General description of what GPS
is and how it works.
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.
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.
Although GPS was designed for military use, many thousands of civi
lians 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.
GPS technology can be used in avariety 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 afleet of trucks, trains,
ships or planes are and how fast they are moving; directin gemergency
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.
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