What is GPS?
The GPS is a navigational system that calculates position from accurate US aviation satellites. This system allows you to track down your exact location on the earth. The GPS satellites are located in six orbits, 20,000 km above us. The GPS consists of a total of 24 GPS satellites: Four of the satellites are placed into each orbit, and at least three satellites are required to pinpoint your location. A GPS receiver receives radio signals from the satellites, and calculates the present location based on the orbital information (almanac data) and travel time of the signals, etc.
Measuring a location is called “tracking”. A GPS receiver can track down the location’s latitude and longitude by receiving signals from three satellites.
GB
10