Happy 20th, GPS
- By Amanda Ziadeh
- Jul 16, 2015
Exactly 20 years ago, the technology that airplane pilots and lost tourists alike depend on was deemed at “full operational capability” by the Air Force Space Command.
Originally a Department of Defense invention, the global positioning system is run by the Second Space Operations Squadron (2 SOPS ) at Schriever Air Force Base in Colorado Springs, Colo., which tracks the satellites via a global monitoring network and manages their status on a daily basis.
The base manages the $3.6 billion GPS constellation of more than 30 operational satellites from a master control station, and also uses a network of ground antennas at 16 worldwide monitoring stations that send data updates and operational commands to the satellites.
GPS satellites broadcast radio signals with their locations, status and precise time. When a GPS device receives the radio signals, it notes their exact time of arrival and calculates its distance from each satellite in view. Once a GPS device knows its distance from at least four satellites, it can use basic geometry to determine its location.
The highly accurate position, velocity and timing data from GPS has “revolutionized nearly every aspect of modern warfare,” according to a Schriever fact sheet. The system also has more than 3 billion users worldwide depending on it for air, road, rail and marine navigation, precision agriculture, telecommunications, recreation and emergency response.
In the two decades this program has been operational, the number of GPS-enabled devices worldwide has grown to four billion, and is expected to double in the next five years, according to the Colorado Space Coalition.
Because of GPS’ beneficial impact on the economy of Colorado, Gov. John Hickenlooper officially declared July 17 “GPS Day” to highlight the state’s continued support for aerospace innovation, business and technology.
Amanda Ziadeh is a former reporter/producer for GCN.