gps

"GPS" redirects here. For other uses, see GPS (disambiguation).
Geodesy
Fundamentals
Geodesy Geodynamics Geomatics Cartography
Concepts
Datum Geographical distance Geoid Figure of the Earth Geodetic system Geodesic Geographic coordinate system Horizontal position representation Latitude / Longitude Map projection Reference ellipsoid Satellite geodesy Spatial reference system
Technologies
Global Navigation Satellite System (GNSS)
Global Positioning System (GPS)
GLONASS (Russian)
Galileo (European)
Indian Regional Navigational
Satellite System (IRNSS)
Beidou-2 (Chinese)
Standards
ED50 European Datum 1950
SAD69 South American Datum 1969
GRS 80 Geodetic Reference System 1980
NAD83 North American Datum 1983
WGS84 World Geodetic System 1984
NAVD88 N. American Vertical Datum 1988
ETRS89
European Terrestrial Reference
System 1989
Spatial Reference System Identifier (SRID)
Universal Transverse Mercator (UTM)
History
NAVD29 (Sea Level Datum 1929)
v t e

Artist's conception of GPS Block II-F satellite in Earth orbit.

Civilian GPS receivers ("GPS navigation device") in a marine application.

Automotive navigation system in a taxicab.

U.S. Air Force Senior Airman runs through a checklist during Global Positioning System satellite operations.
The Global Positioning System (GPS) is a space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites.[1] The system provides critical capabilities to military, civil and commercial users around the world. It is maintained by the United States government and is freely accessible to anyone with a GPS receiver.

The GPS project was developed in 1973 to overcome the limitations of previous navigation systems,[2] integrating ideas from several predecessors, including a number of classified engineering design studies from the 1960s. GPS was created and realized by the U.S. Department of Defense (DoD) and was originally run with 24 satellites. It became fully operational in 1995. Bradford Parkinson, Roger L. Easton, and Ivan A. Getting are credited with inventing it.

Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS system and implement the next generation of GPS III satellites and Next Generation Operational Control System (OCX).[3] Announcements from Vice President Al Gore and the White House in 1998 initiated these changes. In 2000, the U.S. Congress authorized the modernization effort, GPS III.

In addition to GPS, other systems are in use or under development. The Russian Global Navigation Satellite System (GLONASS) was developed contemporaneously with GPS, but suffered from incomplete coverage of the globe until the mid-2000s.[4] There are also the planned European Union Galileo positioning system, India's Indian Regional Navigational Satellite System and Chinese Compass navigation system.