1、北斗卫星导航系统（Beidou satellite navigation system）Beidou satellite navigation systemPublished: 2011-9-19 21:27:01 Views: 99 : small fontsBeidou satellite navigation system is developed by Chinese regional active 3D satellite positioning and communication system (CNSS), in addition to Americas global posit
2、ioning system (GPS), after the Russian GLONASS third sophisticated satellite navigation system. Beidou satellite navigation system is committed to the global users to provide high quality positioning, navigation and timing service, its construction and development will follow the openness, autonomy,
3、 compatibility and gradual progress of the 4 principles.brief introductionBeidou satellite navigation system, BeiDou (COMPASS) Navigation Satellite System, is a global satellite navigation system, independent research and development, Chinese is implementing the independent operation of the.Schemati
4、c diagram of the Beidou satellite navigation systemBeidou satellite navigation system by the end of the space, the ground end and user end is composed of three parts, including 5 end space satellites in geostationary orbit and non geostationary orbit 30 satellites, the ground terminal comprises a ma
5、in control station, into the station and monitoring station several ground stations, the user terminal composed by Beidou user terminal and compatible with the United States GPS, Russia GLONASS, GALILEO and other European satellite navigation system.China had been successfully launched four Beidou n
6、avigation satellite test and three Beidou navigation satellite system, will be in the network and on the basis of experiment, and gradually extended to the global satellite navigation system.targetBeidou satellite navigation system aims to build a global coverage of the Beidou satellite navigation s
7、ystem independent, open and compatible, built with advanced technology, stable and reliable, promote the satellite navigation industry chain formation, the formation of a sound national satellite navigation industry support, promotion and support, promote the applications of satellite navigation in
8、the national economic and social sectors.Schematic diagram of the Beidou satellite navigation systemThere are 4 sets of satellite navigation systems in the world at present: Chinese compass, American GPS, the Russian GLONASS, the European Galileo satellite navigation system is an important infrastru
9、cture space, has brought great economic and social benefits for human beings. Chinese as a developing country, has a vast territory and sea area, attaches great importance to the construction of satellite navigation system, exploring and developing with satellite navigation and positioning system wi
10、th independent intellectual property rights.Since 2000, Chinese has successfully launched 4 Beidou navigation satellite test, built Beidou navigation experiment system (first generation system). This system has the localization, in the range of China and its surrounding areas in the timing, message
11、and GPS wide area differential function, and has been in the mapping, telecommunications, water conservancy, transportation, fishery, exploration, forest fire prevention and national security and other areas to gradually play an important role.Chinese composition is the construction of the Beidou sa
12、tellite navigation system, the space segment consists of 5 satellites in geostationary orbit and non geostationary orbit 30 satellites, provides two kinds of services, namely open service and authorization service (which belongs to the second generation system). Open service is free in the service a
13、rea to provide positioning, velocity and timing services, positioning accuracy of 10 meters, the timing accuracy of 50 ns, measurement accuracy of 0.2 meters per second. The authorization service is to provide positioning, more secure to authorized users speed, timing and communication service and i
14、ntegrity information system.Chinese plans around 2012, the Beidou system will cover the Asia Pacific region, around 2020 global coverage. Our country is carrying out the construction of the Beidou satellite navigation system, has successfully launched four Beidou navigation satellite. According to t
15、he overall planning, system construction about 2012, the system will first have to cover the Asia Pacific region of positioning, navigation and timing and short message communication service capability; built around 2020, global coverage Beidou satellite navigation system.courseSchematic diagram of
16、the Beidou satellite navigation systemSatellite navigation system is an important spatial information infrastructure. Chinese attaches great importance to the construction of satellite navigation system, satellite navigation system has independent intellectual property rights in the exploration and
17、development efforts. In 2000, the first built Beidou navigation test system,China has become the United States and Russia after the worlds third country with autonomous navigation satellite system. The system has been successfully applied in surveying and mapping, telecommunications, water conservan
18、cy, fishery, transportation, forest fire prevention, disaster relief and public security and other fields, has significant economic and social benefits. Especially in the 2008 Beijing Olympic Games, Wenchuan has played an important role in earthquake relief. In order to better serve the national con
19、struction and development, to meet the global application demand, our country started to implement the construction of the Beidou satellite navigation system.navigation satellitefirstIn April 14, 2007, Chinese successfully launched first Beidou navigation satellite.Schematic diagram of the Beidou sa
20、tellite navigation systemSecondIn April 15, 2009 16, China with a “Long March three rocket from the Xichang satellite launch center, the success of the second Beidou navigation satellite into orbit. Chinese satellite navigation engineering center responsible person, the Beidou navigation satellite l
21、aunch (COMPASSG2), is China Beidou satellite navigation system (COMPASS, BeiDou, Chinese name) second satellite network construction plan, the geosynchronous orbit satellite. The successful launch of the satellite has a very important significance for the construction of the Beidou satellite navigat
22、ion system.Satellite navigation system is an important space infrastructure that can provide high precision positioning, velocity measurement and time service, can bring enormous social and economic benefits. China attaches great importance to the construction of satellite navigation system, has bee
23、n working to explore and develop satellite navigation system with independent intellectual property rights. Beidou navigation test system has been built China, plays an important role in surveying and mapping, telecommunications, water conservancy, transportation, fishery, exploration, forest fire p
24、revention and national security etc At present, is carrying out the construction of the Beidou satellite navigation system.The launch of the satellite and rocket are developed by China Aerospace Science and Technology Corporation owned Chinese Research Institute of space technology and China rocket
25、technology research institute. This is the long march rocket flight 116th.Third0:12 on January 17, 2010, Chinas “Long March three rocket from the Xichang satellite launch center, the success of the third Beidou navigation satellite into orbit, which marks the construction of Beidou satellite navigat
26、ion system project is an important step, satellite network is steadily according to plan.Schematic diagram of the Beidou satellite navigation systemAccording to the Chinese satellite navigation engineering center responsible person, is the implementation of the Beidou satellite navigation system (CO
27、MPASS, Chinese, named BeiDou) construction work, planning launched 5 satellites in geostationary orbit and non geostationary orbit 30 satellites, built Beidou satellite navigation system covering the whole world. Previously, has successfully launched two Beidou navigation satellite, the satellite in
28、to geostationary orbit satellite. In 2012, according to the construction plan, the Beidou satellite navigation system will be the first to provide coverage in the Asia Pacific region navigation, timing and short message communication service ability. Around 2020, built global coverage Beidou satelli
29、te navigation system.FourthThe evening of June 2, 2010 at 23:53, Chinas “Long March three rocket from the Xichang satellite launch center, the fourth Beidou navigation satellite into space orbit, which marks the network construction of the Beidou satellite navigation system is an important step, Chi
30、na satellite navigation system project management office responsible person said, at present, Chinese Beidou navigation satellite launch network has entered the intensive stage.Beidou satellite navigation system is a global satellite navigation system of autonomous development, China is implemented
31、independently, its construction goal: to build a global coverage of the Beidou satellite navigation system independent, open and compatible, advanced technology, stable and reliable, promote the satellite navigation industry chain formation, the formation of a sound national satellite navigation ind
32、ustry support and promotion and security system, promote the wide application of satellite navigation in the national economic and social sectors.Working principleThe working process of the Beidou satellite navigation system is: first to the satellite I and satellite II and sends the interrogation s
33、ignal from the central control system via satellite transponder to users in radio service area. One of the satellites, the user response to the interrogation signal, and also to the two satellite transmits a response signal via satellite transmitted to the central control system. The central control
34、 system to receive and demodulate the users signal, the corresponding data processing according to the application user and service content. The location for the central control system, measure two time delay: from the center of the control system sends out the interrogation signal by a satellite fo
35、rwarded to users, the user sends positioning response signal delayed by the same satellite transmitted to the central control system; and a request signal from the central control, the same satellite arrived the user, user sends a response signal, the delay of another satellite transmitted to the ce
36、ntral control system. Because of the central control system and two satellite locations are known, so from the above two delay amount can be calculated by the user to the first satellite distance, and users to two satellites and distance, so as to know the user in a first satellite for a sphere surf
37、ace, and to two. As the intersection between satellite focus on ellipsoid. In addition to the central control system from the storage in the computer digital topographic map to search the user can know the user elevation value in a parallel and ellipsoidal earth reference ellipsoid surface. To the c
38、entral control system can finally calculate the 3D coordinates of the point where the user, the coordinate encrypted by outbound signal sent to the user.Schematic diagram of the Beidou satellite navigation systemShort message communication: one can transmit up to 120 messages Chinese characters.Prec
39、ision timing accuracy: up to 10 ns.Positioning accuracy: the level of accuracy of 100 meters (1 sigma), after the establishment of the calibration station is 20 meters (similar to differential state). Working frequency: 2491.75MHz.System capacity: 540000 households per hour.Construction principleThe
40、 construction and development of the Beidou satellite navigation system, in order to promote the application and development of industry as the basic goal, not only to build the system, but also to use the system, emphasis on quality, safety, efficiency, application, follow the following principles
41、of construction:1, open. The construction of the Beidou satellite navigation system development and application will be open to the world, to provide high quality services for free users worldwide, and actively carry out exchanges and cooperation with other countries in the world widely and deeply,
42、promoting the compatible satellite navigation systems and interoperability, promote the development of satellite navigation technology and industry.2, autonomy. Chinese self construction and operation of the Beidou satellite navigation system, Beidou satellite navigation system can provide services
43、for independent users worldwide.3, compatibility. The International Committee on global navigation satellite systems (ICG) and ITU (ITU) under the framework of the Beidou satellite navigation system and the satellite navigation system to achieve compatibility and interoperability, so that all users
44、can enjoy the fruits of the development of satellite navigation.4, progressive. China will actively and steadily push forward the construction and development of the Beidou satellite navigation system, and constantly improve the service quality, and realize the seamless connection of each stage.Comp
45、ared with the GPS systemCoverageBeidou navigation system is China local coverage area navigation system. The coverage of about 70 degrees -140 degrees east longitude, latitude 5 degrees -55. GPS is an all-weather navigation system covering the whole world, to ensure that any place on the earth at an
46、y time can also observed 6-9 satellites (in fact, most can be observed in 11).Schematic diagram of the Beidou satellite navigation system advantagesThe number of satellites and orbital characteristicsBeidou navigation system is a set of 2 geostationary satellites in the earths equatorial plane, sate
47、llite equatorial angular distance is about 60 degrees. GPS is a set of 24 satellites in 6 orbital planes, equatorial orbit at an angle of 55 degrees, 60 degrees angle equatorial orbit plane. GPS navigation satellite orbit for quasi synchronous orbit around the earth, 11 hours and 58 minutes a week.T
48、he positioning principleBeidou navigation system is active two-way ranging two-dimensional navigation.The center of the ground control system solution for the user, three-dimensional positioning data. GPS is a passive pseudo code ranging 3D navigation. Is your solution independent of three-dimension
49、al positioning data from the user equipment. The working principle of Beidou “has two aspects, one is the user location and lost radio concealment, the military is adverse, on the other hand, because the equipment must include a transmitter, so in the volume, weight, price and power consumption at a disadvantage.positioning accuracyThe 3D positioning accuracy of the Beidou navigation system about several tens of meters, the timing accuracy of about 100ns. GPS 3D positioning accuracy P code has increased from 16m to 6m, the C/A code has been increased from 25-100m to 12M, the ti
