Sistema De Posisionamiento Global

Global Positioning System



"GPS" redirects here. For other uses, see GPS (disambiguation).



Geodesy



Fundamentals



­Geodesy ·
­Geodynamics ·
­Geomatics ·
­Cartography



Concepts



­Datum ·
­Distance ·
­Geoid ·
­Fig. Earth ·
­Geodetic system ·
­Geodesic ·
­Geog. coord. system ·
­Hor. pos. represent. ·
­Lat. / Long. ·
­Map proj. ·­Ref. ellipsoid ·
­Satellite geodesy ·
­Spatial ref. system



Technologies



­GNSS ·
­GPS ·
­GLONASS ·
­IRNSS



Standards



­ED50 ·
­ETRS89 ·
­GRS 80 ·
­NAD83 ·
­NAVD88 ·
­SAD69 ·
­SRID ·
­UTM ·
­WGS84



History



­History of geodesy ·
­NAVD29




­v ·
­t ·
­e






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




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




Automotive navigation system in a taxicab.




GPS receivers are now integrated in many mobile phones.




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 satellitenavigation system that provides location and time information in all weather, anywhere on or near the Earth, where there is an unobstructed line of sight to four or more GPS satellites. It is maintained by the United States government and is freely accessible to anyone with a GPS receiver.

The GPS program provides critical capabilities to military, civil and commercial users around the world. Inaddition, GPS is the backbone for modernizing the global air traffic system.

The GPS project was developed in 1973 to overcome the limitations of previous navigation systems,[1] 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 24satellites. It became fully operational in 1994.

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).[2] Announcements from the Vice President and the White House in 1998 initiated these changes. In 2000, U.S. Congressauthorized the modernization effort, referred to as GPS III.

In addition to GPS, other systems are in use or under development. The Russian GLObal NAvigation Satellite System (GLONASS) was in use by only the Russian military, until it was made fully available to civilians in 2007. There are also the planned European Union Galileo positioning system, Chinese Compass navigation system, and IndianRegional Navigational Satellite System.





Contents
[hide] 1 History 1.1 Predecessors
1.2 Development
1.3 Timeline and modernization
1.4 Awards

2 Basic concept of GPS
3 Structure 3.1 Space segment
3.2 Control segment
3.3 User segment

4 Applications 4.1 Civilian 4.1.1 Restrictions on civilian use

4.2 Military

5 Communication 5.1 Message format
5.2 Satellitefrequencies
5.3 Demodulation and decoding

6 Navigation equations 6.1 Bancroft's method
6.2 Trilateration
6.3 Multidimensional Newton-Raphson calculations
6.4 Additional methods for more than four satellites

7 Error sources and analysis
8 Accuracy enhancement and surveying 8.1 Augmentation
8.2 Precise monitoring
8.3 Timekeeping 8.3.1 Leap seconds
8.3.2 Accuracy
8.3.3 Format8.4 Carrier phase tracking (surveying)

9 Regulatory spectrum issues concerning GPS receivers
10 Other systems
11 See also
12 Notes
13 References
14 Further reading
15 External links


[edit] History

The design of GPS is based partly on similar ground-based radio-navigation systems, such as LORAN and the Decca Navigator developed in the early 1940s, and used during...