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How GPS Works

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Welcome everyone!!!
You ask yourself ...what is GPS?
Well ...a synopsis to GPS technology. It is compose of Global Positioning System satellites transmit signals to equipment on the ground. GPS receivers passively receive satellite signals; they do not transmit. GPS receivers require an unobstructed view of the sky, so they are used only outdoors and they often do not perform well within forested areas or near tall buildings. GPS operations depend on a very accurate time reference, which is provided by atomic clocks at the U.S. Naval Observatory.
More on this topic can be found at  ;)

Thank U for the sharing of the knowledge of GPS!

GPS is a fleet of more than 24 communications satellites that transmit signals globally around the clock. With a GPS receiver, one can quickly and accurately determine the latitude, the longitude.

A single GPS receiver can find its own position in seconds from GPS satellite signals to an accuracy of one meter; accuracy within one centimetre can be achieved with sophisticated military specification receivers.

he Global Positioning System (GPS) is actually a constellation of 27 Earth-orbiting satellites  (24 in operation and three extras in case one fails). The U.S. military developed and implemented this satellite network as a military navigation system, but soon opened it up to everybody else.
Each of these 3,000- to 4,000-pound solar-powered satellites circles the globe at about 12,000 miles (19,300 km), making two complete rotations every day. The orbits are arranged so that at any time, anywhere on Earth, there are at least four satellites "visible" in the sky.
A GPS receiver's job is to locate four or more of these satellites, figure out the distancĀ­e to each, and use this information to deduce its own location. This operation is based on a simple mathematical principle called trilateration. Trilateration in three-dimensional space can be a little tricky, so we'll start with an explanation of simple two-dimensional trilateration.


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