Global Positioning System - Civilian Navigation

The system consists of a constellation of at least 24 satellites in 6 orbital planes. The GPS satellites were initially manufactured by Rockwell and now manufactured by Lockheed Martin. The first was launched in February 1978, and the most recent was launched September 25, 2005. Each satellite circles the Earth twice every day at an altitude of 20,200 kilometres (12,600 miles). The satellites carry atomic clocks and constantly broadcast the precise time according to their own clock, along with administrative information including the orbital elements of thei ...

See also:

Global Positioning System, Global Positioning System - Applications, Global Positioning System - Military, Global Positioning System - Civilian Navigation, Global Positioning System - Precise Time Reference, Global Positioning System - GPS for the visually impaired, Global Positioning System - Geocaching, Global Positioning System - GPS tracking, Global Positioning System - GPS on airplanes, Global Positioning System - Technical description, Global Positioning System - GPS Time, Global Positioning System - Sources of GPS measurement errors, Global Positioning System - Clocks, Global Positioning System - Ionosphere, Global Positioning System - Multipath, Global Positioning System - GPS Jamming, Global Positioning System - Selective Availability, Global Positioning System - Techniques to improve GPS accuracy, Global Positioning System - System reliability, Global Positioning System - GPS and Relativity, Global Positioning System - GPS is free for private and commercial use, Global Positioning System - Awards, Global Positioning System - Other systems

Read more here: » Global Positioning System: Encyclopedia II - Global Positioning System - Technical description

For a list of other systems, see satellite navigation system. ...

See also:

Global Positioning System, Global Positioning System - Applications, Global Positioning System - Military, Global Positioning System - Civilian Navigation, Global Positioning System - Precise Time Reference, Global Positioning System - GPS for the visually impaired, Global Positioning System - Geocaching, Global Positioning System - GPS tracking, Global Positioning System - GPS on airplanes, Global Positioning System - Technical description, Global Positioning System - GPS Time, Global Positioning System - Sources of GPS measurement errors, Global Positioning System - Clocks, Global Positioning System - Ionosphere, Global Positioning System - Multipath, Global Positioning System - GPS Jamming, Global Positioning System - Selective Availability, Global Positioning System - Techniques to improve GPS accuracy, Global Positioning System - System reliability, Global Positioning System - GPS and Relativity, Global Positioning System - GPS is free for private and commercial use, Global Positioning System - Awards, Global Positioning System - Other systems

Read more here: » Global Positioning System: Encyclopedia II - Global Positioning System - Other systems

Two GPS developers have received the National Academy of Engineering Charles Stark Draper prize year 2003: Ivan Getting, emeritus president of The Aerospace Corporation and engineer at the Massachusetts Institute of Technology established the basis for GPS, improving on the World War II land-based radio system called LORAN (Long-range Radio Aid to Navigation). Bradford Parkinson, teacher of aeronautics and astronautics ...

See also:

Global Positioning System, Global Positioning System - Applications, Global Positioning System - Military, Global Positioning System - Civilian Navigation, Global Positioning System - Precise Time Reference, Global Positioning System - GPS for the visually impaired, Global Positioning System - Geocaching, Global Positioning System - GPS tracking, Global Positioning System - GPS on airplanes, Global Positioning System - Technical description, Global Positioning System - GPS Time, Global Positioning System - Sources of GPS measurement errors, Global Positioning System - Clocks, Global Positioning System - Ionosphere, Global Positioning System - Multipath, Global Positioning System - GPS Jamming, Global Positioning System - Selective Availability, Global Positioning System - Techniques to improve GPS accuracy, Global Positioning System - System reliability, Global Positioning System - GPS and Relativity, Global Positioning System - GPS is free for private and commercial use, Global Positioning System - Awards, Global Positioning System - Other systems

Read more here: » Global Positioning System: Encyclopedia II - Global Positioning System - Awards

Ideally, GPS receivers would easily be able to convert the C/A and P(Y)-code measurements into accurate positions. However, a system with such complexity leaves many openings for errors to affect the measurements. The following are several causes of error in GPS measurements. Global Positioning System - Clocks. Both GPS satellites and receivers are prone to timing errors. Ground stations throughout the world monitor the satellites to ensure that their atomic clocks are kept synchronized. Receiver clock err ...

See also:

Global Positioning System, Global Positioning System - Applications, Global Positioning System - Military, Global Positioning System - Civilian Navigation, Global Positioning System - Precise Time Reference, Global Positioning System - GPS for the visually impaired, Global Positioning System - Geocaching, Global Positioning System - GPS tracking, Global Positioning System - GPS on airplanes, Global Positioning System - Technical description, Global Positioning System - GPS Time, Global Positioning System - Sources of GPS measurement errors, Global Positioning System - Clocks, Global Positioning System - Ionosphere, Global Positioning System - Multipath, Global Positioning System - GPS Jamming, Global Positioning System - Selective Availability, Global Positioning System - Techniques to improve GPS accuracy, Global Positioning System - System reliability, Global Positioning System - GPS and Relativity, Global Positioning System - GPS is free for private and commercial use, Global Positioning System - Awards, Global Positioning System - Other systems

Read more here: » Global Positioning System: Encyclopedia II - Global Positioning System - Sources of GPS measurement errors

Global Positioning System - Military. The primary military purposes are to allow improved command and control of forces through improved locational awareness, and to facilitate accurate targeting of smart bombs, cruise missiles, or other munitions. The satellites also carry nuclear detonation detectors, which form a major portion of the United States Nuclear Detonation Detection System. < ...

See also:

Global Positioning System, Global Positioning System - Applications, Global Positioning System - Military, Global Positioning System - Civilian Navigation, Global Positioning System - Precise Time Reference, Global Positioning System - GPS for the visually impaired, Global Positioning System - Geocaching, Global Positioning System - GPS tracking, Global Positioning System - GPS on airplanes, Global Positioning System - Technical description, Global Positioning System - GPS Time, Global Positioning System - Sources of GPS measurement errors, Global Positioning System - Clocks, Global Positioning System - Ionosphere, Global Positioning System - Multipath, Global Positioning System - GPS Jamming, Global Positioning System - Selective Availability, Global Positioning System - Techniques to improve GPS accuracy, Global Positioning System - System reliability, Global Positioning System - GPS and Relativity, Global Positioning System - GPS is free for private and commercial use, Global Positioning System - Awards, Global Positioning System - Other systems

Read more here: » Global Positioning System: Encyclopedia II - Global Positioning System - Applications

The GPS signal is more fragile than might be supposed. A network of at least 24 satellites is required for full coverage. Satellites cannot be repaired and have a limited life. As of 2005: there are 28 satellites in orbit, of which 16 are already beyond their design life—the oldest have nearly reached twice their design life. The failure rate is about two satellites per year.