GPS

Global Positioning System (GPS) is the only satellite navigation system that works properly. This system uses 24 satellites that send signals to Earth Microwave. Signal is received by the recipient in the tool surface, and is used to determine position, speed, direction, and time. System similar to GPS anatara other Russian GLONASS, Galileo the European Union, India IRNSS.

This system was developed by the Department of Defense the United States, with the full name is NAVSTAR GPS (common mistake is that the NAVSTAR is an acronym, this is wrong, NAVSTAR is the name given by John Walsh, an important policy determination in the GPS program). [1] This collection of satellites managed by the 50th Space Wing United States Air Force. Treatment system is approximately U.S. $ 750 million per year, [2] including the replacement of older satellites, and research and development.