BeiDou satellite. (Photo : CNSA)
China claims its BeiDou Navigation Satellite System (BDS) is now as accurate as the United States' dominant Global Positioning System (GPS), but admits it will take a lot of work to convince Chinese, including the military, to switch to BDS from GPS.
BDS was originally developed as a military system intended to wean the People's Liberation Army (PLA) from its over dependence on GPS, a weakness the U.S. could exploit in the event of a war. And the military version of BDS (which isn't available to the general public) is far more accurate than the civilian version.
The free civilian version of BDS is now accurate to within centimeters and is on par with GPS, claims Xu Ying, a researcher at the Academy of Opto-Electronics of the Chinese Academy of Sciences and a major developer of BDS.
She said BeiDou can even offer more precise positioning services than GPS within China. She noted more support is needed from the central government to make Chinese GPS users and the PLA switch to BDS.
Xu said she's not sure how many users within the PLA have transferred to BDS despite the Chinese system having improved security against interference and interception. The PLA depends on GPS and BDS to guide its missiles towards targets hundreds of kilometers distant.
The BDS version used by the PLA is said to be accurate to within 0.1 meters (10 centimeters). The current civilian version is accurate to 10 meters.
In contrast, the free civilian version of GPS is accurate to five meters. GPS, a U.S. government project, became operational in 1995.
Only the PLA and the Pakistan Armed Forces (China's close ally) use the military version of BDS.
Xu's new claim the civilian BDS is accurate to centimeters means a huge leap forward in accuracy, and should be held in doubt since China hasn't yet completed the constellation of BDS satellites that should make this accuracy possible.
The complete BDS satellite constellation will consist of 35 in orbit satellites. There are currently 23 in orbit satellites, a number sufficient to cover China and neighboring countries. China plans to launch 20 more BDS satellites (including spares) by 2020.
