The Compass Navigation Satellite Experimental System, or BeiDou-1 in its Chinese name, is the three-satellite constellation developed by China Academy of Space Technology (CAST). It is China’s first space-based regional navigation and positioning network. The system provides all-weather, two-dimensional positioning data for both military and civilian users. The network covers most areas of East Asia region and has both navigation and communication functions. The satellite network comprises three BeiDou-1 satellites (two operational and one backup).
China began to study the satellite navigation and positioning technology as early as the late 1960s. However, development in establishing an operational satellite network has been slow due to lack of fund and technical difficulties. China first developed the “Twin-Star” regional navigation theory in the mid-1980s, and has tested it on two DFH-2A communications satellites in 1989. This test showed that the precision of the Twin-Star system would be comparable to the the publicly available signals of the United States Global Positioning System (GPS). An independent experimental satellite navigation system was given go-ahead by Chinese leaders in 1993.
The first two satellites of the BeiDou-1 navigation experimental system, the BeiDou-1A and BeiDou-1B, were launched from Xichang Satellite Launch Centre on 31 October 2000 and 21 December 2000 respectively. The system began to provide navigation and positioning services in late 2001. The third satellite (backup) BeiDou-1C was launched on 25 May 2003, bringing the system fully operational. The navigation and positioning services became available to civilian users in April 2004. This has made China the third country in world to have deployed an operational space-based navigation and positioning network. |
