Beijing:The Chinese government on Thursday released a white paper elaborating on the action plan for the BeiDou Navigation Satellite System (BDS), which has been independently developed and operated by Beijing. China has formulated a three-step strategy for developing the BDS. The aim is to complete the deployment of the 35 satellite constellation around 2020 to provide services to global users, Xinhua news agency reported. This is the first white paper on the navigation satellite system. Initially, China aimed to provide services to domestic users. The next stage featured the expansion of the network to cover the Asia-Pacific region, which was achieved by the end of 2012. Currently, B1I and B2I open service signals are being broadcast by the operating BDS-2, providing open services to the Asia-Pacific region free of charge, according to the white paper. The services cover an area between 55 degrees north latitude and 55 degrees south latitude, and between 55 and 180 degrees east longitude, with positioning accuracy less than 10 metres, velocity measurement accuracy less than 0.2 metres per second, and timing accuracy less than 50 nanoseconds. BDS spokesperson Ran Chengqi said tests in the Asia-Pacific region showed the system to be performing well. Ran, who is also Director of China's Satellite Navigation System management office, said in priority cities including Beijing and Urumqi, the capital city of Xinjiang Uygur region, positioning accuracy was less than 5 metres. The BDS will provide all-time, all-weather and high-accuracy positioning, navigation and timing services to global users, according to the document. The BeiDou project was formally launched in 1994. However, the first BeiDou satellite was not launched until 2000. The 23rd satellite was launched on Sunday. According to the document, the BDS is designed to provide open satellite navigation services free of charge. International cooperation and exchanges on navigation satellite systems will be encouraged and the BDS compatibility with other systems will be enhanced to provide better services to end users. Products related to the BDS have been used in areas including communication and transportation, marine fisheries, weather forecasting, mapping and geographic information, forest fire prevention.