Ground system improves satellite navigation precision

WUHAN, March 22 (Xinhua) -- A ground system aimed at enhancing the navigation precision of China's homegrown BeiDou Navigation Satellite System (BDS) was approved in central China's Hubei Province on Friday.

The BeiDou Ground Base Enhancement System (BGBES), a network consisting of 30 ground base stations, an operating system and a precision positioning system, was approved by the evaluation committee led by Sun Jiadong, an academician with the Chinese Academy of Sciences (CAS) and chief designer of the BDS.

The system is expected to help improve the BDS' positioning precision to 2 centimeters horizontally and 5 centimeters vertically via tri-band real-time precision positioning technology, and to 1.5 meters with the single-frequency differential navigation technology.

The former technology, which is much more precise, will be used in special industries like mapping, land resources, urban construction, planning and water conservation, as well as national construction projects. The latter will be put into public use, including vehicle positioning services, said Shi Chuang, director of the global navigation satellite system research center of Wuhan University.

Planned by the central government, the BGBES was built by the center and the Hubei Provincial Surveying and Mapping Bureau as a national pilot project.

The system, which now covers all of Hubei Province on a trial basis, will be further established across China to better meet the needs of BDS users, said Shi.

Liu Jingnan, an academician with the Chinese Academy of Sciences (CAS) and professor with Wuhan University, said the BGBES has helped improve positioning precision, sensitivity and positioning speed to a great extent, enabling the BDS to compete with the U.S.-developed Global Positioning System (GPS).

Liu said he believes the BGBES project had reached, and in some parts exceeded, international standards. "The BDS has entered a new era of high precision," he said.

He said in China, fields such as mapping and urban construction have been largely dependent on GPS, and the homegrown BDS positioning technology will reduce this dependence to a large extent.

The BDS began providing services to civilian users in China and surrounding areas in the Asia-Pacific region at the end of last year. It aims to take a share of the GPS-dominated domestic market.

China launched the first satellite for the BDS in 2000, and a preliminary version of the system has been used in traffic control, weather forecasting and disaster relief work on a trial basis since 2003.