Satellite navigation

A satellite navigation or satnav system could be a system that uses satellites to produce autonomous geo-spatial positioning. It permits tiny electronic receivers to see their location (longitude, latitude, and altitude/elevation) to high preciseness (within a couple of metres) mistreatment time signals transmitted on a line of sight by radio from satellites. The system will be used for providing position, navigation or for trailing the position of one thing fitted with a receiver (satellite tracking). The signals additionally permit the electronic receiver to calculate this time to high preciseness, that permits time synchronisation. Satnav systems operate severally of any telecom or net reception, tho' these technologies will enhance the quality of the positioning data generated.

A satellite navigation system with world coverage could also be termed a worldwide navigation satellite system (GNSS). As of Dec 2016 solely the u. s. NAVSTAR world Positioning System (GPS), the Russian GLONASS and therefore the European Union's uranologist ar world operational GNSSs. the ecu Union's uranologist GNSS is scheduled to be totally operational by 2020.[1] China is within the method of increasing its regional BeiDou Navigation Satellite System into the worldwide BeiDou-2 GNSS by 2020.[2] Asian nation presently has satellite-based augmentation system, GPS power-assisted GEO increased Navigation (GAGAN), which reinforces the accuracy of NAVSTAR GPS and GLONASS positions. Asian nation has already launched the IRNSS, with Associate in Nursing operational name NAVIC (Navigation with Indian Constellation), a constellation of satellites for navigation in and round the Indian landmass. it's expected to be totally operational by June 2016. France and Japan ar within the method of developing regional navigation systems additionally.

Global coverage for every system is usually achieved by a satellite constellation of 18–30 medium Earth orbit (MEO) satellites unfold between many orbital planes. the particular systems vary, however use orbital inclinations of >50° Associate in Nursingd orbital periods of roughly twelve hours (at an altitude of regarding twenty,000 kilometres or twelve,000 miles).