Car Satelite Navigation
The Car Sat Nav or car satellite navigation now has revolutionized. Satellite navigation devices are now fitted in almost every vehicle such as airliners, boat, taxi drivers, couriers and the family car.
Navigation like car sat nav is just one of the main uses of GPS. To make travelling comfortable and trouble free to find unfamiliar destinations, car sat nav GPS pin point locations from space.
Sat Nav or satellite navigation relies on a constellation of satellites known as GNSS (Global Navigational Satellite Systems). And the Global Positioning System (GPS) is only one fully functioning GNSS in the world today.
GPS has a constellation of more than 30 satellites. For accurate navigation, at any one time at least three or four of these satellites are overhead. The GPS satellites each have onboard an atomic clock that use the resonance of an atom (the frequency at particular energy states) which makes them highly accurate, over a million years not lose as much as a second in time. It is really unbelievable precision that makes car sat nav possible.
The satellites relay a signal from the onboard clock that consists of the time and the position of the satellite. Then, this signal is beamed back to earth where your car’s sat nav retrieves it. The computer in your GPS system will result exactly where you are on the face of the earth by calculation how long this signal took to reach the car and triangulating four of these signals. It is only required three signals on a ‘flat’ earth and four signals if the elevation changes.
GPS systems can only work as a result of the highly precise accuracy of the atomic clocks. GPS systems signals are relay at the speed of light and accuracy of even a millisecond. It could adjust the positioning calculations by 100 kilometers as light can travel nearly 100 kilometers each and every second, although currently GPS systems are accurate to about five meters.
As I was writing the above article, it struck me that you may be interested in reading this too: How To Choose The Best GPS Systems (3) – Now What Do I Choose? and The Review of Magellan GPS Receiver I hope you find it useful.
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