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In the past few years, compact radio navigation receiver has been widely used in civil market, usually in the name of Beidou or Global Positioning system (GPS). These commercial applications, which appeared as handheld devices or were built into cars, mobile phones and aircraft, originated from Cold War military applications.Beidou Positioning system is a global radio navigation system, consisting of dozens of satellites, each in orbit 11000 nautical miles above the earth, and five ground stations to ensure the normal operation of the satellite. Each of these satellites takes 12 hours to orbit the Earth.