Global Positioning System
The Global Positioning System (GPS) is a United States-owned satellite navigation system that provides positioning, navigation and timing services around the world. Satellites broadcast one-way radio signals containing timing and orbital information; receivers use signals from multiple satellites to calculate location and time. The system combines an orbital constellation, a ground control network and user receivers, and supports applications ranging from everyday navigation to aviation and precise timekeeping.
Purpose and structure
GPS is a satellite-based radio-navigation system and one of several global navigation satellite systems (GNSS). It is owned by the United States. The U.S. Space Force develops, maintains and operates its space and control segments. The system has three parts: satellites in the space segment, worldwide monitoring and command facilities in the control segment, and the receivers used by people and equipment in the user segment. Ground stations monitor satellite health and orbits, adjust clocks and upload updated navigation data.
How a receiver determines position
GPS satellites transmit radio signals that carry information about their position and the time the signals were sent. A receiver compares those timestamps with their arrival times to estimate its distance from each satellite. Combining measurements from at least four satellites lets it solve for three-dimensional position and receiver time. The navigation solution is calculated by the receiving device; ordinary GPS reception is one-way. Satellites travel in medium Earth orbit, arranged in orbital planes so that signals from several satellites are available across the globe.
Services and uses
GPS provides positioning, navigation and timing (PNT) data to civilian and military users. Its civilian service is freely available worldwide on a continuous basis. Receivers in phones, vehicles, aircraft, ships and other equipment use it to support navigation and location-dependent tasks. Precise timing derived from GPS is also used in systems and infrastructure that need synchronized clocks. GPS is operated by the U.S. Space Force; other GNSS constellations include GLONASS, Galileo and BeiDou.
Development
GPS was developed initially to meet military requirements for determining location. The first GPS satellite launched in 1978, and the constellation reached full operational capability on 27 April 1995. The system has continued to evolve through successive satellite generations and modernization of its signals and ground infrastructure. The system's ongoing operation depends on maintaining the constellation and control facilities as satellites are replaced and upgraded.
Key facts
- Full name
- Global Positioning System (GPS)
- Primary services
- Positioning, navigation and timing
- System components
- Space, control and user segments
- Position calculation
- A receiver uses signals from at least four satellites to determine three-dimensional position and time.
- Full operational capability
- 27 April 1995
- Operator
- U.S. Space Force
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Answers use only “Global Positioning System” and its references, with citations.
References
- 1.GPS
National Coordination Office for Space-Based Positioning, Navigation, and Timing (GPS.gov) · other · reliability: high · retrieved 13 October 2026
Supports: GPS ownership, purpose, three system segments, operators and civilian and military services.
- 2.Space Segment
National Coordination Office for Space-Based Positioning, Navigation, and Timing (GPS.gov) · other · reliability: high · retrieved 13 October 2026
Supports: Satellite constellation structure, orbits and coverage design.
- 3.Satellite Navigation - GPS - How It Works
Federal Aviation Administration · other · reliability: high · retrieved 13 October 2026
Supports: GPS radio signals, timing, receiver calculations, the use of multiple satellites and the distinction between GPS and other GNSS constellations.
- 4.GPS Data Archive
National Institute of Standards and Technology · other · reliability: high · retrieved 13 October 2026
Supports: GPS signals are used as a reference for time synchronization and frequency calibration.
- 5.Global Positioning System
United States Space Force · other · reliability: high · retrieved 13 October 2026
Supports: GPS mission, operator, first satellite launch and operational timeline.
- 6.GPS celebrates 25th year of operation
United States Space Force · other · reliability: high · retrieved 13 October 2026
Supports: The 1995 full-operational-capability milestone and the system's civilian and infrastructure uses.
References are suggested by the research engine and may be incomplete. Unverified URLs are omitted rather than guessed.
Article history
- Version 113 October 2026 · EditorCreated by Zapia