How Does a GPS Even Work?
When it comes to ignorance to the functioning of those miracles of modern science known as "global positioning systems," there are two types of people: the blissfully ignorant and the slightly curious. We're venturing to guess that you're part of the latter group, which is why you've come across this article. Here, in a nutshell, is how the GPS products that fill your cars and mobile phones work their magic.
First, the entire GPS grid is based on around 24 to 32 satellites orbiting the Earth at any given time; while you're already familiar with its common uses in automobiles and mobile phones, it has significance for map-making, studying earthquakes, and even synchronizing the actual time. This system went operational in 1995 and has been aiding our navigation ever since. As it turns out, you can thank the good old U.S. of A. for this system, as the U.S. has opened up the GPS for wider usage. Each satellite orbits the Earth at the speed of about two "rotations" per day, which means you might end up using different satellites throughout the day - as you'll see later on.
When most people are talking about a "GPS," they're actually talking about the device that receives the signals to what is more properly called the global positioning system - the aforementioned network of satellites.
A receiver takes the information from three or four satellites closest by and uses the relay of these satellites to calculate its own location on Earth. This is useful in navigation in your car when coupled with a computer that uses pre-loaded maps to interpret this information and give you directions; the only things the satellites do are tell your receiver where it is.
This is where the high degree of variability in each GPS comes into play, as different GPS receivers will have different functions ranging from live traffic reports to voice readings of individual street names. It's the twist these companies give on the GPS that makes them different, and worth researching.
The next time you head out in your car, keep in mind that the satellites your receiver is using to deduce its location are possibly different than the ones you used earlier. It's this quiet, unnoticed system that keeps our cell phones buzzing with navigational information and our car receivers ready to dole out directions.
| Click On An Item For More Information |
 TomTom XL 340S Car GPS Receiver US $102.50 |
 TomTom XL 340S Car GPS Wide Touchscreen 1EM005202 US $119.00 
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 TOMTOM GO XL 340S CAR GPS NAVIGATION 43 US CANADA MAP US $117.95 |
