A GPS Primer
By Jackie Gately
Use of the Global Positioning System (GPS) is becoming commonplace for navigation and tracking purposes alike. While we enjoy the novelty and benefits of GPS navigation and tracking tools, the first application was military in nature – and it really wasn’t that long ago. But what exactly is behind the “magic” and how did it evolve?
In 1957, when the Soviet Union launched Sputnik (the first satellite) into orbit, researchers at Massachusetts Institute of Technology (MIT) made an interesting observation: as Sputnik approached their location, its radio signal increased; and as Sputnik became more distant, the radio signal decreased. Using this information combined with the knowledge of their own position, the researchers were able to determine Sputnik’s location. It was this discovery upon which GPS technology is based.*
In 1960, Transit was the first satellite navigation system used by the United States Navy. It used five satellites in tandem to determine and report a location about once every hour. The Pentagon later began developing the Navstar Global Positioning System in an effort to create an error proof satellite system for military strategies. They launched a total of 24 GPS satellites between 1978-1993.
Simply stated, GPS uses microwave signals transmitted from a network of satellites as a basis to determine ground position. The military uses this technology for a range of applications, including navigation, target tracking, missile and projectile guidance, search and rescue, reconnaissance and map creation, and as a major portion of the United States Nuclear Detonation Detection System.
The need for civilian use became obvious after Korean Air Lines Flight 007 strayed and was shot down in a Soviet no-fly zone. In response, President Ronald Reagan made GPS available for civilian use in a limited capacity. In 2000, President William Clinton ordered the removal of signal degradation and other military restrictions.
To date, civilian GPS applications include navigation, GPS tracking devices, fleet management, search and rescue, and more. You can plan a trip, find your way home, locate or track a vehicle, person or other object – all courtesy of positioning data from satellites maintained by the US Air Force 50th Space Wing.
* American scientist, Roger L. Easton, Sr. received the distinguished National Medal of Technology in 2006 and has long been acclaimed as the principal inventor and designer of GPS.
Jackie Gately is a freelance writer. She can be reached at jackiegately.wordpress.com or located by GPS.
Posted: under GPS Tracking Systems.
Tags: , Global Positioning System, network, satellite, technology, tracking
Comments (0)
Jan 22 2009
