How Does GPS Work

GPS is a system of 30+ navigation satellites circling Earth1. To determine your location, a GPS receiver in your phone listens for signals from these satellites1. The receiver calculates its distance from four or more GPS satellites, and uses this information to figure out where you are1.Alternatively, GPS works as follows2:
Tracking stations use radio signals to determine orbits of GPS satellites.
Command center transmits orbital data, time corrections, and location of other satellites in the GPS constellation.
GPS satellites simultaneously transmit synchronized time and orbital data to Earth.
GPS receivers compute location using orbital data and the difference in arrival times of the signals of at least 4 satellites.