China is in its second stage of its project to build an independent satellite navigation system.

At this stage of the Beidou Navigation System, scientists are setting up 35 satellites to cover China and the entire Asia-Pacific region by 2012.

The system is expected to cover the whole world by 2020. But while satellites are operating well in space, researchers say much more work is needed on the ground.

China completed the first stage of the project from 2000 to 2003. The first stage consisted of three satellites. It's been offering navigation services, mainly for customers in China. That has made China the third country after the US and Russia to have such a system developed on its own.

But as the chief designer of the project puts it, the future development of it calls for further improvements on the ground to cooperate with the satellites.

Sun Jiadong, Chief Designer, Beidou Navigation System, said, "The navigation system needs market operations on the ground. Imagine a time when we are able to send more than 30 satellites into space quickly. That means an investment of tens of billions yuan. If there isn't a suitable market on the ground it would be a big waste of money."

The chief designer says the building and application of the system will be a challenging task in the coming decade. He hopes the country can make use of its biggest application market of global satellite navigation, and further its capability in providing wider and better services.