China says it will have 30 satellites in its Beidou navigation system by 2020 to improve accuracy to within inches to better compete with the U.S.GPS.

The Beidou network, with 16 satellites serving the Asia-Pacific region, currently has an accuracy of about 15 feet but Chinese officials say they want to upgrade it to compete with the U.S. global positioning system, the most widely used worldwide, ZDNet reported Monday.

Six satellites were added to the system last year; the network has been operational since December 2011.

The state-owned China Aerospace Science and Technology Corp. said it was encouraging other Asian countries to take advantage of its system by offering the service for free, as the United States does with its GPS network.

Completion of the Beidou system would also contribute to China's national defense, Ran Chengqi, director of the China Satellite Navigation Office, said.

"Satellite navigation is an important part of a country's infrastructure, and it's certainly a combined civilian and military infrastructure," Ran said.