How GPS Monitoring Works

Global Positioning System (GPS) monitoring works due to the triangulation of satellites orbiting the earth. Twenty-four satellites are used in all.
To "triangulate" means that a GPS receiver measures distance using the travel time of radio signals. When a user's GPS ankle unit reads the signals sent to it by the satellites, these signals can provide information as to the wearer's location, speed of movement and direction of movement.

Active VS Passive GPS Measuring

Active GPS transmits its location at near real-time intervals and can include immediate alert notifications.
Passive GPS transmits its location at set intervals and alert notifications are usually received the next day.

Use of GPS Data