Accuracy of Beidou system is improving

Testing underway for equipment sent up in November; global coverage planned by 2020

China's third-generation Beidou Navigation Satellite System has begun to take shape and continues to improve its accuracy, a program leader said.

Ran Chengqi, director of the China Satellite Navigation Office, told the audience at a conference in Harbin, Heilongjiang province, on Wednesday that an initial network of Beidou's third-generation satellites has been formed with eight orbiting satellites.

The satellites were launched in four groups starting in November and are undergoing in-orbit testing and operational evaluations, he said. The tests so far show they work well.

More than 2,500 officials, industry representatives and researchers from around the world attended the three-day China Satellite Navigation Conference.

Before year's end, China plans to send 10 third-generation Beidou satellites to medium Earth orbit and another one to geostationary orbit. In the coming two years, six such satellites are scheduled to be placed in medium Earth orbit, three to inclined geosynchronous satellite orbits and two to geostationary orbits, Ran said.

Compared with the system's second-generation satellites, the new model features clearer navigation signals, better stability and extra applications such as an intersatellite link and global emergency search capabilities.

The third-generation Beidou network will have a positioning accuracy of 2.5 to 5 meters, which can be improved with the assistance of ground-based augmentation stations, Ran said.

Yang Changfeng, Beidou's chief designer, said at the conference that Beidou's ground-based augmentation network is complete and is midway through a trial run. The network will enable Beidou to provide centimeter-level accuracy in navigation and positioning, he said.

Beidou is one of the four space-based navigation networks in operation, along with the United States' GPS, Russia's GLONASS and the European Union's Galileo.

Since 2000, when the first Beidou satellite was placed in orbit, 33 satellites have been launched for the network. Beidou began serving civilian users in China and parts of the Asia-Pacific region in December 2012.

The network will have 35 satellites before the end of 2020 - with several now in orbit decommissioned - to give Beidou global coverage, according to plans from the satellite navigation office.