How do GPS Receivers Work?GPS receivers receive signals from satellites which are stationed in a geostationary orbit. As the name suggests, these receivers merely receive the signal and are not built for transmission.For the successful and clear transmission of the signals, it is important that the GPS receivers are in the clear line of sight of the satellite, which is the reason why they don't work in cemented or real jungles. The GPS satellites have inbuilt atomic clocks. These satellites are well in sync with each other and keep transmitting data such as the time and the location. At any given time, there are 24 satellites working which are controlled by the US Air force. Each satellite sends a signal to the GPS receiver. The time taken by the receiver to receive these signals helps in calculating the distance of the satellites from the receiver. When three such satellites transmit signals to the receiver simultaneously, then it helps in determining the coordinates like latitude, longitude and altitude. This is to say that through the low power radio signal transmitted by the satellites, it becomes possible to know the distance between the GPS receiver and the distance of each of the satellites from the receiver. The process is known as trialteration which is based on the principles of Pythagoras. Generally the accuracy of these GPS receivers is about 10-20 meters. The receivers with a higher accuracy use a process called Differential GPS or DGPS. In this method, a stationary point is fixed in at a previously determined location which helps in correcting the coordinates tabulated by the satellites. The accuracy of the DGPS is 1 meter or more. Top of Page---> How do GPS Receivers Work? Back to GPS Navigation Articles Home---> GPS Navigators
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