How Does A GPS Receiver Work?

A GPS receiver is similar to a cell phone where operation is concerned. It works through radio waves. However, it uses the direct signals from satellites instead of the tower on ground. These are GPS satellites that orbit the earth. There are 27 such GPS satellites in orbit. A GPS receiver can determine your location through the location of the 3 satellites above you. It finds out your location in relation to the location of the 3 satellites. Then, the receiver draws a circle around the determined satellites. These circles intersect in two points, in space and on ground. The point on the ground where the circles intersect is your location.