Global Positioning System Wikipedia. This article is about the American satellite navigation system. It is not to be confused with similar non American global and regional systems. For similar systems, see Satellite navigation. Amateur Satellite Tracking Software' title='Amateur Satellite Tracking Software' />Ham Radio Deluxe Software is the Radio Amateurs Best Asset for Logbook, Digital Modes, Satellite. Try Ham Radio Deluxe FREE Before You Buy It This page is listing the Amateur radio satellites. Select any Amateur radio satellite listed to learn additional details, perform live tracking or see satellites. Driver Improvement Test Answers on this page. Global Positioning System GPSCountryies of origin. United States. OperatorsAFSPCType. Military, civilian. Status. Operational. Coverage. Global. Accuracy. 5 meters. Constellation size. Total satellites. Satellites in orbit. Quicktime For Windows Vista 32 Bit here. First launch. February 1. Amateur Satellite Tracking Software' title='Amateur Satellite Tracking Software' />Total launches. Orbital characteristics. Regimes6x MEO planes. Orbital height. 20,1. The Global Positioning System GPS, originally Navstar GPS,12 is a space based radionavigation system owned by the United States government and operated by the United States Air Force. It is a global navigation satellite system that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites. The GPS does not require the user to transmit any data, and it operates independently of any telephonic or internet reception, though these technologies can enhance the usefulness of the GPS positioning information. The GPS provides critical positioning capabilities to military, civil, and commercial users around the world. The United States government created the system, maintains it, and makes it freely accessible to anyone with a GPS receiver. The GPS project was launched by the U. S. Department of Defense in 1. United States military and became fully operational in 1. It was allowed for civilian use in the 1. Advances in technology and new demands on the existing system have now led to efforts to modernize the GPS and implement the next generation of GPS Block IIIA satellites and Next Generation Operational Control System OCX. Announcements from Vice President Al Gore and the White House in 1. In 2. 00. 0, the U. S. Congress authorized the modernization effort, GPS III. In addition to GPS, other systems are in use or under development, mainly because the US government can selectively deny access to the system, as happened to the Indian military in 1. Kargil War, or degrade the service at any time. The Russian Global Navigation Satellite System GLONASS was developed contemporaneously with GPS, but suffered from incomplete coverage of the globe until the mid 2. GLONASS can be added to GPS devices, making more satellites available and enabling positions to be fixed more quickly and accurately, to within two meters. There are also the European Union Galileo positioning system, Chinas Bei. Dou Navigation Satellite System, Indias NAVIC and Japans Quasi Zenith Satellite System. HistoryeditThe GPS project was launched in the United States in 1. The U. S. Department of Defense developed the system, which originally used 2. It was initially developed for use by the United States military and became fully operational in 1. It was allowed for civilian use in the 1. Amateur Radio Information, Ideas and Suggestions from Ham Radio Operator K3RRR Kilo Three Triple R Amateur Radio Station For Fun, Emergencies and Preppers. Roger L. Easton of the Naval Research Laboratory, Ivan A. Getting of The Aerospace Corporation, and Bradford Parkinson of the Applied Physics Laboratory are credited with inventing it. 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 1. British Royal Navy during World War II. Friedwardt Winterberg1. Special and general relativity predict that the clocks on the GPS satellites would be seen by the Earths observers to run 3. Earth. The GPS calculated positions would quickly drift into error, accumulating to 1. This was corrected for in the design of GPS. Amateur Satellite Tracking Software' title='Amateur Satellite Tracking Software' />PredecessorseditThe Soviet Union launched the first artificial satellite, Sputnik 1, in 1. Two American physicists, William Guier and George Weiffenbach, at Johns Hopkinss Applied Physics Laboratory APL, decided to monitor Sputniks radio transmissions. Within hours they realized that, because of the Doppler effect, they could pinpoint where the satellite was along its orbit. The Director of the APL gave them access to their UNIVAC to do the heavy calculations required. The next spring, Frank Mc. Clure, the deputy director of the APL, asked Guier and Weiffenbach to investigate the inverse problem  pinpointing the users location, given that of the satellite. At the time, the Navy was developing the submarine launched Polaris missile, which required them to know the submarines location. This led them and APL to develop the TRANSIT system. In 1. 95. 9, ARPA renamed DARPA in 1. TRANSIT. 1. 41. The first satellite navigation system, TRANSIT, used by the United States Navy, was first successfully tested in 1. It used a constellation of five satellites and could provide a navigational fix approximately once per hour. In 1. 96. 7, the U. S. Navy developed the Timation satellite, which proved the feasibility of placing accurate clocks in space, a technology required by GPS. In the 1. 97. 0s, the ground based OMEGA navigation system, based on phase comparison of signal transmission from pairs of stations,1. Limitations of these systems drove the need for a more universal navigation solution with greater accuracy. While there were wide needs for accurate navigation in military and civilian sectors, almost none of those was seen as justification for the billions of dollars it would cost in research, development, deployment, and operation for a constellation of navigation satellites. During the Cold Wararms race, the nuclear threat to the existence of the United States was the one need that did justify this cost in the view of the United States Congress. This deterrent effect is why GPS was funded. It is also the reason for the ultra secrecy at that time. The nuclear triad consisted of the United States Navys submarine launched ballistic missiles SLBMs along with United States Air Force USAF strategic bombers and intercontinental ballistic missiles ICBMs. Considered vital to the nuclear deterrence posture, accurate determination of the SLBM launch position was a force multiplier. Precise navigation would enable United States ballistic missile submarines to get an accurate fix of their positions before they launched their SLBMs. The USAF, with two thirds of the nuclear triad, also had requirements for a more accurate and reliable navigation system. The Navy and Air Force were developing their own technologies in parallel to solve what was essentially the same problem. To increase the survivability of ICBMs, there was a proposal to use mobile launch platforms comparable to the Russian SS 2. SS 2. 5 and so the need to fix the launch position had similarity to the SLBM situation. In 1. 96. 0, the Air Force proposed a radio navigation system called MOSAIC MObile System for Accurate ICBM Control that was essentially a 3 D LORAN. A follow on study, Project 5. GPS concept was born. That same year, the concept was pursued as Project 6. B, which had many of the attributes that you now see in GPS2. Air Force bombers as well as ICBMs. Updates from the Navy TRANSIT system were too slow for the high speeds of Air Force operation. The Naval Research Laboratory continued advancements with their Timation Time Navigation satellites, first launched in 1. Another important predecessor to GPS came from a different branch of the United States military. In 1. 96. 4, the United States Army orbited its first Sequential Collation of Range SECOR satellite used for geodetic surveying.