GPS

Global Positioning System is popularly known as GPS. It uses 24 medium Earth orbit satellites and receivers to transmit radio signals. This system of satellites and receivers helps to determine the exact location of people, vehicles and devices. GPS was developed by the United States Department of Defence. The first GPS satellite was launched in 1974 and the 24th satellite was launched in 1994. These 24 satellites orbit the earth twice in a day. GPS equipped devices get transmissions from a few of these satellites, which help to get accurate information.

The GPS unit receives multiple signals from the satellites and it uses these signals to calculate the distance between itself and GPS satellites. The receiver’s position is calculated on the basis of triangulation of various signals. The GPS is used in military for tracking and targeting different weapons. GPS is also used in navigation, for land surveying and for making maps. It is used in the scientific study of earthquakes and synchronization of telecommunications networks. Apart from military personnel, GPS is commonly used by civilians.

Today, many cars are equipped with GPS to aid the drivers in navigation. Fisherman and hikers use portable GPS devices to help them navigate through unknown areas. Many manufacturers make GPS devices that include many useful features. Now-a-days, GPS receivers are integrated into cell phones and watches, making them convenient to use. Many manufacturers are involved in making GPS devices and some of them include Garmin GPS, Magellan GPS, Medion GPS and Sony GPS, among others.