|
Three Main Components To The System
The three main components of the global positioning system include the satellites, the ground control stations and the receivers. There are dozens of satellites currently orbiting earth that transmit their signals, which are digital code sequences of ones and zeros. These satellites move twenty thousand kilometres above earth and are constantly being used. On the ground, there are ground control stations and satellite upload facilities that are maintained by the U.S. Air Force. This system is running around the clock and is an all season service.
The third component to the GPS system is the receiver that can be used by both civilians and military personnel. The receiver works to receive satellite signals. There is no limit to the amount of receivers that can use the GPS system at any time.
Pinpoint Your Position Through Satellites Twenty Thousand Kilometres Away
How the GPS works to pinpoint the position of a receiver is that when a receiver makes a GPS request through the unique code sequence that is given, four or more satellites are matched and the distance between the receiver and the satellites are measured and an accurate position can be given from these calculations. This is called trilateration and is not to be confused with triangulation.
Each receiver is pre-loaded with the coordinates of the satellites before a civilian or military person uses their receiver. Depending on the type of receiver that you have, the accuracy of the positions that you receive may be accurate to within ten to twenty meters. The Differential GPS receivers are much more accurate than the hand-held GPS receivers, while the stationary GPS receivers can be accurate to within one meter.
How the GPS works is a wonder of the new modern age. When you consider how the GPS works, it is a fantastic feat to think that our GPS receivers can communicate simultaneously with satellites that float twenty thousand kilometres above the earth and receive an instantaneous answer to let us know where we are at any given moment.
|
