GPS 101: How does GPS work?

“GPS” has become such a common household term that we don’t really think about the underlying technology itself. It’s everywhere — in our cars, on our phones, and in the workplace — so it’s easy to just dismiss it as a sort of “magic wand” that just gives us the information we want, when we want it. But what exactly is it? How does it perform that magic?

GPS stands for Global Positioning System, also known as NAVSTAR. It is a network of 24 satellites that orbit the Earth twice per day at an altitude of 12,000 miles and a speed of 7,000 miles per hour. The satellites receive signals from Earthbound transmitting units and then relay them back to the Earth’s surface, where a GPS receiver picks them up and uses them to figure out the precise location of the object sending out the signal. But one signal by itself doesn’t provide enough information — the receiver must take the same signal from at least three different satellites. It then compares the relay times of all three signals to determine the object’s latitude, longitude, and direction/speed. And there it is — you’re tracking an object with GPS! If you add yet another relayed signal from a fourth satellite, you can also determine the object’s altitude.

GPS was originally developed for the U.S. military. The 24 satellites didn’t all make it into space at once — the first unit achieved orbit in 1978, and Number 24 completed the set in 1994. In 1996 the satellite network was declared “dual-use” so the public could use it too. Ever since then, we’ve been finding new and more innovative ways to enhance our everyday lives through GPS technology. It can enhance your business as well — contact us to learn more!