On October 31, 2000, China launched the first satellite of its own navigation and positioning system, named Beidou after the group of stars known in the west as the plough, on a Long March rocket from the launch centre at Xichang in Sichuan province. It was an experimental satellite, and it was followed by a second in December 2000, and the pair provided a regional service that covered China and the neighbouring area. A third satellite was added in 2003. The work began here. The system was built because the country did not want to depend on the American and Russian networks, which can be restricted in wartime.
The first phase worked differently from the later system. It used satellites in high orbits and a ground station to calculate a position and to send it back to the user, rather than the user receiving signals from several satellites and working out the position alone, and the arrangement served a limited number of users and was mainly for use by the armed forces, by mapping and by transport and disaster relief. It was the third such system in the world after the American and Russian networks.
The programme was expanded in stages. A second phase with more satellites went into service from 2012 and gave a service over much of Asia and the Pacific, and a third phase with a large constellation in several orbits was completed in 2020, when the last satellite was placed in orbit, and the system then offered a global service. The satellites carry clocks and transmitters and broadcast signals on several frequencies, and the ground segment includes a network of stations and control centres.
The service is used for navigation in cars and ships and aircraft, and for the timing signals that telephone, power and banking networks need, and for the tracking of vehicles, and for surveying and for disaster response, and it also carries a short message function that allows a user in a remote area to send a text. That feature saves lives. The system grew. The system is one of the cases where a country built its own infrastructure rather than rely on another power, and the first launch in 2000 was the beginning of that effort.