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. Essentially,

the GPS receiver measures the distance to each

satellite by the amount of time it takes to receive

a transmitted signal. With distance measurements

                                                                   from a few more satellites, the receiver can determine

                                                                   a user's position and display it electronically to measure

                                                                   your running route, or anywhere.

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