The GPS(Global Positioning System) is a U.S-owned utility that provides users with positioning, navigation, and timing(PNT) services. This system consists of three segments: the space segment, the control segment, an the user segment.
GPS satellites circle the earth twice a day in a precise orbit. Each satellite transmits a unique signal and orbital parameters that allow GPS devices to decode and compute the precise location of the satellite. GPS receivers use this information and trilateration to calculate a user’s exact location.