China announced on Friday it would launch more advanced satellites in 2014 to continue the "three-step" development of its homegrown BeiDou Navigation Satellite System (BDS), which is intended to offer global coverage by 2020.

Ran Chengqi, director of the China Satellite Navigation Office, said at the conference on Friday that the new satellites would perform twice as well as previous ones and their service time can be prolonged to 10 to 15 years.

A new open service signal, B2I, was also unveiled on Friday, marking BDS the first system to possess two civil navigation signal frequencies with full service capacity, after the first civil signal, B1I, was introduced in 2012.

The interface control document (ICD) for the new service signal was also issued at the conference. On its basis, companies home and abroad could develop dual-frequency BDS receivers.

BDS has been providing the Asia-Pacific region with services including positioning, navigation, timing and short messages since December 27, 2012, regarded as successful completion of the second step of the BDS development strategy.

"The release of dual-frequency signal would provide a higher precision service, thus improving precision from 10 meters to the meter or even decimeter level. The system performance has met the designed specification of 10-meter positioning accuracy. The performance is even better in some areas, such as Beijing, Urumqi and other cities, where the accuracy reaches seven meters," said Ran.

Besides BDS, there are three global satellite navigation systems, namely, the US-developed GPS, the EU's Galileo and Russia's Glonass.

Fu Song, a professor at the School of Aerospace of Tsinghua University, told the Global Times that it may take some time before GPS users turn to BDS, which has a very small market share at present, but he believed BDS could take market share in the long run.