Centuries ago, our ancestor has found some ways to keep them in track while doing a journey. They count the monumental landmarks, read the star positions, draw simple maps, and even make symbols on the road just to avoid them from getting lost. What a marvelous, complex thing! But then as the time goes by, we don’t have to do such things as them in the past. The technology saves us. There is a Global Positioning System that will help us to find the right location without getting lost. From now on, you don’t have to read the stars or erect the landmarks anymore. All you need to do is reading the information on the GPS. At first, this invention is used by the military to find a location and give the soldiers’ location to the base. But then it spreads out to the public.
When you talk about GPS, it mostly is about the GPS receiver. It is a system of navigation that relies on the 24 satellites that orbit on the Earth. There are 3 more satellites if one of the 24 satellites is failed. The satellites run the Earth more less 12.000 miles above Earth surface and shape 2 perfect orbits in every 24 hours. GPS then transmits radio digital signals and data on the location of the satellite and the precise time to the receiver that is on the Earth. The signals are transmitted in the speed of light. The longer the time to reach the receiver, the farther the distance of the satellite is. If GPS uses three satellites, it will get the information of longitude and latitude, based on the location of the three satellites intersects. If GPS uses four satellites, it will also calculate the altitude.
The GPS is now available in the simpler shape. It is now completed on the smart phones, cars, and watches. For the common people, it is used as the tool to navigate them to find the location. And for the businessman, it can be used as the fastest way to find the location, forestry, cartography, find the management of wildlife habitat, the potential spot of mineral exploration, monitors the people movement, and show the exact time on the Earth. It sure will help them a lot.