How Does GPS Work


The GPS or Global Positioning System is composed of 24 satellites that travel around the earth. They are divided into six groups with four satellites each, going on different orbital tracks. The first GPS satellite was launched in 1978. Today there are approximately 2500 satellites orbiting around the earth. GPS uses radio frequencies to track down the exact location. How does the GPS work?

Before the manner by which GPS functions is discussed, you must understand first how people benefit from these satellites. First, the military has used the Global Positioning System in fighting and winning battles. It has provided military men with the position of the enemies. Second, the GPS system has enabled you to watch some shows live.

The Miss Universe Beauty Pageant, World Football Championships and news that show what is actually happening in other parts of the world are all brought to you by the GPS system. Third, your cellular phone cannot function well without the GPS. It needs this system to connect you to the internet so that you can use some of its functions. GPS, nowadays is used in wars, ships, planes, cell phones, cars and many more.

You might wonder how your position or the place where you are can be configured by the global positioning system or GPS. By using the GPS, Google maps came into being, making it easier than before for travelers to find their destination or to determine where they are at the moment.  Cars that have GPS receivers and were car napped were easily found by using the GPS.  A GPS system can tell you far you have traveled, what is the shortest route to your destination, your current speed and your current direction. This is how the GPS system works. A GPS receiver can predict 10-20 meter of accuracy. This however, also depends on the type of receiver. Some GPS receivers use DGPS (Differential GPS) to get much better accuracy.

The satellites are located 20,000 miles above the surface of the earth. The satellites have radio transmitters that send signals to earth. Anyone who has a GPS receiver can catch these signals. The receivers can be small devices like the cellular phones or bigger ones like car antennas. The receivers need to have a clear view of the satellites in the sky.

If the view is unobstructed, a good signal is received and data are transmitted clearly. Have you noticed that during bad weather, your cellular phone may not work well, as well as your internet connection? This is because the signal is obstructed by the clouds and disturbed by the bad weather. Also, if you live in forested areas or in places surrounded by hills and mountains, you will encounter problems in using your cellular phones.

Watch this video to get more detailed info on how GPS works.

One most frequent occurrence in these areas is dropped calls. You are in the middle of a conversation and then, you cannot hear well the voice of the other person. There are also instances when your messages reach the recipient late. This is because of the obstruction to the signal from the satellites.

In case of Google maps, the satellites can pinpoint a location room a few meters away to a few inches, depending on the number of satellites that have honed in on the target. The principle of triangulation is used in determining position. Each circle covered by the three satellites will only intersect at a single point.

The intersection is where the object that is detected, is located. The more satellites circles interest at one point, the more accurate is the position of the object whose location is being searched.  A position cannot be fixed if there are less than three satellites that can detect it.