You turn on your car’s GPS navigation system or fire up your handheld unit and it tells you where you are and how to get where you are going - thats how you work it, but have you ever wondered how this technology really works and how it got its start?
It all began back in the late 1970’s and early 80’s when the US Department of Defense installed over 24 satellites in orbit over earth to track global positioning. In 1983, former president Ronald Regan began allowing public access to these satellites and a world of GPS opportunities were born.
Soon, technology companies began creating units that were able to interface with these satellites in order to determine the absolute global position of a GPS receiver and they built software programs and devices that made this technology useful for your average person.
These days, there are many useful applications of GPS technology. There are vehicle navigation systems, hand held navigation systems, marine navigation systems and more - and that’s just in consumer products. Of course, there are other applications of this technology in the military and other fields.
When you power up your GPS receiver, it will transmit a signal to the satellites (generally 4 or more at a time) and the computer in your unit will calculate your position based upon a triangulation of the time it takes to receive a signal back from the satellite. More simply put, you can think of it like bouncing a beam out in to space and measuring the time it takes it to bounce back from the different satellite points.
All of the other fancy things that todays GPS receivers do is thanks to the software that they run. Maps, directions and other uses are computer programs that run on the receiver and are based on a database of the GPS coordinates of known places.
While far from a technical explanation of GPS technology, I hope this article helps you better understand your favorite gadget and how it works.