A space-based radio navigation and positioning system that provides users with all-weather three-dimensional coordinates and velocity and time information on the Earth’s surface or anywhere in near-Earth space. GPS applications: fine Agriculture, Scientific Research (Field Biology, Meteorology, Geoscience), Environmental Monitoring, Emergencies
And disaster assessment, safety and security, celestial and architectural engineering and natural resource analysis positioning. The satellite navigation system has brought enormous social and economic benefits to mankind. So far, the relatively perfect satellite navigation system has already had the American GPS and the Russian GLONASS system. Europe plans to launch its own satellite navigation system Galileo..
It is estimated that by 2020, the four major GNSS systems of GPS, GLONASS, EU GALILEO and China Beidou Satellite Navigation system will be completed or modernized.