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進(jìn)入英語學(xué)習(xí)論壇下載音頻

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.

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.

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.

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.

China is now 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; 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.

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, experts say.

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

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

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.

Questions:

1. What is the name of China's satellite positioning system?

2. How many satellites will be orbiting by 2020?

3. What year did China start to reduce its reliance on the GPS?

Answers:

1. Beidou

2. 35

3. 2000

（中國日報(bào)網(wǎng)英語點(diǎn)津 Rosy 編輯）

About the broadcaster:

Emily Cheng is an editor at China Daily. She was born in Sydney, Australia and graduated from the University of Sydney with a degree in Media, English Literature and Politics. She has worked in the media industry since starting university and this is the third time she has settled abroad - she interned with a magazine in Hong Kong 2007 and studied at the University of Leeds in 2009.