BeiDou Navigation Satellite System is China’s global navigation satellite system which has been developed independently.The system’s target: maintain independence and keep the initiative in our own hands,keep open,compatible,stable and reliable on technology, offer global service, thereby accelerating the foundation of navigation satellite industrial chain,consummating the sustaining extending and guaranteeing system,expanding the range of application in the country's economic and social sector.
BeiDou Navigation Satellite System is composed of three parts: the space section, the ground section and the user section. The space section contains 5 geostationary orbit satellites and 30 non-geostationary orbit satellites. The ground section consists of a certan number of stations: including the main control stations, the injectionstations and the monitoring stations. And the user section includes terminators of BeiDou system,and some compatible with other navigation satellite system.
Navigation satellite system is an important infrastructure of space information.China attaches great importance to the construction of such a system, and has been searching and developing the system which possesses independent intellectual property rights for years. In 2000, China set up a BeiDou navigation test system ,which made China the third country in the world capable of developing such a system on its own since the United States and Russia.The test system has been widely applied in areas including communication and transportation, forest fire prevention, disaster forecast, public security and more，making remarkable benefit in social, economic aspects. In the 2008 Beijing Olympic Games and the Wenchuan earthquake in particular, this China-made system played an important role. To further serve the nation’s constructionand development,and meet the needs of the world, China recently put into effect the construction of BeiDou Navigation Satellite System.
The fundamental task of BeiDou Navigation Satellite System constructionand development is, to extend application and boost the growth of space industry. Not only should build the system, but with good system, especially keep the quality, safety, practical and benefits.We stand by the following principles:
A.Open.The construction,development and application of the system will be open to the whole world. We’ll provide high quality service free of charge for users all over the world. China is ready to cooperate with other countries in developing satellite navigation projects,enhance the exchanges of the existing satellite navigation systems，and promote the development of satellite navigation technology and industry.
B.Independent.China will construct and operate the BeiDou Navigation Satellite System independently, and the system can provide global service on its own.
C.Compatibility.China hope that compatiblity and interoperability will be realized between BeiDou and other countries’satellite navigation systems, in the frame of the International Committee on Global Navigation Satellite Systems (ICG) and the International Telecommunication Union（ITU）,making all users sharing the development of satellite navigation.
D.Progressive.China will actively promote BeiDou Navigation Satellite System's construction and development, improve service quality continuously,and realize the seamless integration between each stage.
Now, China is implementing the BeiDou Navigation Satellite System. In accordance with the construction plan, the initial satellite navigation system will provide coverage in the Asia-Pacific region with positioning, navigation, timing, and short-message communication service capabilities. The system isdesigned to provide global coverage around 2020.
The BeiDou Navigation Satellite System will provide global coverage with positioning, navigation and timing services, including two kinds of service modes: an open service and an authorized service. The open service is provided free of charge location, velocity and timing, with positioning accuracy of 10 meters, velocity accuracy of 0.2 meters / second and timing accuracy of 10 nanoseconds. The authorized service provides a more secure position, velocity, timing, and communications services as well as a higher level of integrity.
In order to make BeiDou Navigation Satellite System work better for global service, strengthen compatiblityand interoperability between BeiDou and other countries’satellite navigation systems,and promote satellite positioning, navigation and timing service application, China is willing to cooperate with other countries in developing satellite navigation industry.