China started to run its own satellite positioning system, Beidou, on Tuesday as the country climbed the global tech ladder and challenged the monopoly of the West.

Beidou, or Big Dipper, the domestic version of the US Global Positioning System (GPS), started providing navigation, positioning and timing data on a pilot basis to China and the neighboring area for free on Tuesday, Ran Chengqi, director of the China Satellite Navigation Office, said.

The system, with 10 orbiting satellites, covers an area from Australia in the south to Russia in the north. Signals can reach the Xinjiang Uygur autonomous region in the west and the Pacific Ocean in the east, Ran said.

With six more satellites to be launched next year, the system will cover a wider area and eventually the entire globe by 2020 with a constellation of 35 satellites, he said.

The accuracy of the positioning service will also improve as more satellites orbit.

During the trial run Beidou can offer positioning to within 25 meters but when the system is officially launched next year accuracy will be enhanced to within 10 meters, he said.

With the system operational China is the third member of an elite group, along with the US and Russia, to develop a satellite navigation system.

The US spent 20 years and more than $20 billion on the GPS. Completed in 1994, the system has 24 navigation satellites and is widely used around the world.

Beidou has its own unique features, Ran said.

"It not only tells users where they are and what time it is but also allows users to tell others the information through short messages," Ran said, adding that this feature is being considered by other systems.

Russia's Glonass system achieved a 24-satellite constellation in 1996 but succumbed to funding problems.

The rebuilding of the Glonass system is almost finished and Russian media reported that the system resumed service earlier this month.

The European Union and the European Space Agency are building the Galileo satellite navigation system. Japan and India also intend to build independent regional navigation systems.

"Countries build their own systems because owning an independent satellite navigation system is important to economic development and national security," said Pang Zhihao, deputy editor-in-chief of the monthly publication Space International.

There have long been concerns that the US might take its dominant GPS offline in certain international emergencies.

Ran said that the Beidou system will be "helpful" to national defense.

An "independent and controllable" satellite navigation system can guarantee national economic development as well as scientific and industrial strength, he said.

China started to reduce its reliance on the GPS in 2000, when it sent an experimental pair of positioning satellites into orbit.

But Ran stressed that Beidou is "built for the world", as the compatibility of various systems enhances reliability for users.

"If you only use GPS there will be blind spots. But from demonstrations I saw recently, receivers that are compatible with Beidou will overcome these problems," he said.

He encouraged enterprises at home and abroad to join the research and development of application terminals compatible with Beidou.

The office put a test version of the system's Interface Control Document online on Tuesday, which is a technical document vital for the manufacturing and development of receivers and chips.

The prospects for the country's satellite navigation industry look bright, experts said.

Analysts estimated that around 2020 the industry's output will reach $500 billion globally, including 400 billion yuan ($63 billion) to 500 billion yuan from China.

According to the 2011 Report on Application of Geosaptial Information in China released on Monday, the number of satellite navigation application terminals in China has grown from less than 100,000 in 2000 to more than 10 million in 2009. The number is expected to reach 340 million by 2015.

An insider said a compatible receiver for car use costs 1,600 yuan to 3,000 yuan, higher than a GPS receiver.

"Chips supporting both GPS and Beidou systems have been developed, and terminals have been produced. There are no technical hurdles for the industry," said Han Shaowei, CEO of Beijing-based Unicore Communications Inc, a major navigation chip and core component provider.

Beidou application terminals have been put into use in vehicles, such as government cars in Guangdong province.

Ran said that private terminal makers in Guangdong are testing their receivers on the road, and the products seem stable.

"The price of the compatible terminals is expected to be slashed next year," he said.