Beidou navigation system
Encyclopedia
The BeiDou Navigation System or BeiDou (Compass) Navigation Satellite System is a project by China
to develop an independent satellite navigation system. It may refer to either one or both generations of the Chinese navigation system.
The first BeiDou system, officially called BeiDou Satellite Navigation Experimental System, or known as BeiDou-1, consists of 3 satellites and has limited coverage and applications. It has been offering navigation services mainly for customers in China and from neighboring regions since 2000.
The second generation of the system, known as Compass
or BeiDou-2, which will be a global satellite navigation system consisting of 35 satellites, is still under construction. It is planned to offer services to customers in Asia-Pacific region by 2012 and the global system should be finished by 2020.
The chief designer of BeiDou navigation system is Sun Jiadong
.
constellation
, which is known in Chinese as Běidǒu. The name literally means "Northern Dipper", the name given by Chinese astronomers to the seven brightest stars of Ursa Major or 'the Great Bear' constellation. Historically, this set of stars was used in navigation to locate the North Star Polaris
. As such, BeiDou also serves as a metaphor for the purpose of the satellite navigation system.
According to the China National Space Administration
, the development of the Chinese global navigation system would be carried out in three steps:
The first two satellites, BeiDou-1A was launched on 30 October 2000, BeiDou-1B followed on 20 December 2000. The third satellite BeiDou-1C (as backup satellite), was put into orbit on 25 May 2003. The successful launch of BeiDou-1C also meant the establishment of the BeiDou-1 navigation system.
On November 2, 2006, China announced that from 2008 BeiDou would offer an open service with an accuracy of 10 meters, timing of 0.2 nanoseconds, speed of 0.2 meter/second.
It followed that in February 2007, the fourth and also the last satellite of BeiDou-1 system, the BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.
In April 2007, the first satellite of BeiDou-2, namely Compass-M1 (to validate frequencies for the BeiDou-2 constellation) was successfully put into its working orbit. The second BeiDou-2 constellation satellite Compass-G2 was launched on 15 April 2009. The third satellite (Compass-G1) was carried into its orbit by LM-3C
on January 17, 2010. On the 2nd of June 2010, the fourth satellite was launched successfully into orbit. The fifth orbiter was launched into space by LM-3I carrier rocket from Xichang Satellite Launch Center
on August 1, 2010. Three months later, on November 1, 2010, the sixth satellite was sent into orbit by LM-3C. It is reported that another satellite (BeiDou-2 IGSO) will be launched by the end of the year.
On January 15, 2010 the official website of BeiDou Navigation Satellite System went online.
project and was to invest €
230 million (USD
296 million, GBP
160 million) in Galileo over the next few years. It's believed that China's "BeiDou" navigation system would then only be used by its armed forces. In October 2004, China officially joined the Galileo project by signing the Agreement on the Cooperation in the Galileo Program between the "Galileo Joint Undertaking" (GJU) and the "National Remote Sensing Centre of China" (NRSCC). Based on the Sino-European Cooperation Agreement on Galileo program, China Galileo Industries (CGI), the prime contractor of the China’s involvement in Galileo programs was founded in December 2004. By April 2006, eleven cooperation projects within the Galileo framework had been signed between China and EU.
The Hongkong based South China Morning Post
reported in January 2008 that China was unsatisfied with its role in the Galileo project and was to compete with Galileo in Asian market.
geostationary communications satellite and had a launch weight of 1,000 kilograms (2,200 pounds) each.
Unlike the American GPS, Russian GLONASS
, and European Galileo
systems, which use medium Earth orbit
(MEO) satellites, BeiDou-1 uses satellites in geostationary orbit
(GEO). This means that the system does not require a large constellation of satellites, but it also limits the coverage to areas on Earth where the satellites are visible. The area that can be serviced is from Logitude 70°E to 140°E, and from Latitude 5°N to 55°N.
In 2007, the official Xinhua News Agency
reported that the resolution of the BeiDou system was as high as 0.5 metres, considerably better than unaided GPS. With the existing user terminals appears that the calibrated accuracy is 20m (100m, uncalibrated).
As of 2008, one BeiDou-1 terminal costs about RMB , almost 10 times the price of GPS counterpart. It's said that the reason why is the terminal so expensive is due to "using expensive imported Chips"，but China seemed to have found replacement and the price could lower to less than RMB. By the China High-Tech Fair ELEXCON 2009 (November 16–21, 2009) in Shenzhen
, China
, a terminal solution costing no more than RMB was presented.
According to Sun Jiadong, chief designer of the navigation system, "Many organizations have been using our system for a while, and they like it very much."
As of April 2011, eight satellites for BeiDou-2 have been launched. According to an official report , "the eighth Beidou satellite marks the completion of basic function of Beidou (Compass) Navigation Satellite System...collaborate with five navigation satellites...will be able to provide services to most regions in China after a period of orbiting running tests and system integration."
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
to develop an independent satellite navigation system. It may refer to either one or both generations of the Chinese navigation system.
The first BeiDou system, officially called BeiDou Satellite Navigation Experimental System, or known as BeiDou-1, consists of 3 satellites and has limited coverage and applications. It has been offering navigation services mainly for customers in China and from neighboring regions since 2000.
The second generation of the system, known as Compass
Compass navigation system
The COMPASS system is a project by China to develop an independent global satellite navigation system.COMPASS is not an extension to the previously deployed Beidou-1, but a new GNSS similar in principle to GPS, GLONASS, and Galileo.-General:The new system will be a constellation of 35 satellites,...
or BeiDou-2, which will be a global satellite navigation system consisting of 35 satellites, is still under construction. It is planned to offer services to customers in Asia-Pacific region by 2012 and the global system should be finished by 2020.
The chief designer of BeiDou navigation system is Sun Jiadong
Sun Jiadong
Sun Jiadong , was born in Fuxian, Liaoning Province. He is a Chinese scientist and an expert in carrier rocket and satellite technology...
.
Nomenclature
The BeiDou Navigation System is named after the Big DipperBig Dipper
The Plough, also known as the Big Dipper or the Saptarishi , is an asterism of seven stars that has been recognized as a distinct grouping in many cultures from time immemorial...
constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
, which is known in Chinese as Běidǒu. The name literally means "Northern Dipper", the name given by Chinese astronomers to the seven brightest stars of Ursa Major or 'the Great Bear' constellation. Historically, this set of stars was used in navigation to locate the North Star Polaris
Polaris
Polaris |Alpha]] Ursae Minoris, commonly North Star or Pole Star, also Lodestar) is the brightest star in the constellation Ursa Minor. It is very close to the north celestial pole, making it the current northern pole star....
. As such, BeiDou also serves as a metaphor for the purpose of the satellite navigation system.
BeiDou system
Original ideas of a Chinese satellite navigation system had been conceived and worked on by Chen Fangyun and coworkers in the 1980s.According to the China National Space Administration
China National Space Administration
The China National Space Administration is the national space agency of the People's Republic of China responsible for the national space program. It is responsible for planning and development of space activities...
, the development of the Chinese global navigation system would be carried out in three steps:
- 2000 - 2003: experimental BeiDou navigation system consisting of 3 satellites
- by 2012: regional BeiDou navigation system covering China and neighboring regions
- by 2020: global BeiDou navigation system
The first two satellites, BeiDou-1A was launched on 30 October 2000, BeiDou-1B followed on 20 December 2000. The third satellite BeiDou-1C (as backup satellite), was put into orbit on 25 May 2003. The successful launch of BeiDou-1C also meant the establishment of the BeiDou-1 navigation system.
On November 2, 2006, China announced that from 2008 BeiDou would offer an open service with an accuracy of 10 meters, timing of 0.2 nanoseconds, speed of 0.2 meter/second.
It followed that in February 2007, the fourth and also the last satellite of BeiDou-1 system, the BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.
In April 2007, the first satellite of BeiDou-2, namely Compass-M1 (to validate frequencies for the BeiDou-2 constellation) was successfully put into its working orbit. The second BeiDou-2 constellation satellite Compass-G2 was launched on 15 April 2009. The third satellite (Compass-G1) was carried into its orbit by LM-3C
Long March 3C
The Long March 3C , also known as the Chang Zheng 3C, CZ-3C and LM-3C, is a Chinese orbital carrier rocket. It is launched from Launch Complex 2 at the Xichang Satellite Launch Centre. A 3-stage rocket with two strapon liquid rocket boosters, it is a member of the Long March 3 rocket family, and...
on January 17, 2010. On the 2nd of June 2010, the fourth satellite was launched successfully into orbit. The fifth orbiter was launched into space by LM-3I carrier rocket from Xichang Satellite Launch Center
Xichang Satellite Launch Center
The Xichang Satellite Launch Center also known as Base 27 , is a People’s Republic of China space vehicle launch facility approximately 64 km northwest of Xichang City, Liangshan Yi Autonomous Prefecture in Sichuan Province....
on August 1, 2010. Three months later, on November 1, 2010, the sixth satellite was sent into orbit by LM-3C. It is reported that another satellite (BeiDou-2 IGSO) will be launched by the end of the year.
On January 15, 2010 the official website of BeiDou Navigation Satellite System went online.
Involvement in Galileo
In September 2003, China intended to join the European Galileo positioning systemGalileo positioning system
Galileo is a global navigation satellite system currently being built by the European Union and European Space Agency . The €20 billion project is named after the famous Italian astronomer Galileo Galilei...
project and was to invest €
Euro
The euro is the official currency of the eurozone: 17 of the 27 member states of the European Union. It is also the currency used by the Institutions of the European Union. The eurozone consists of Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,...
230 million (USD
United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....
296 million, GBP
Pound sterling
The pound sterling , commonly called the pound, is the official currency of the United Kingdom, its Crown Dependencies and the British Overseas Territories of South Georgia and the South Sandwich Islands, British Antarctic Territory and Tristan da Cunha. It is subdivided into 100 pence...
160 million) in Galileo over the next few years. It's believed that China's "BeiDou" navigation system would then only be used by its armed forces. In October 2004, China officially joined the Galileo project by signing the Agreement on the Cooperation in the Galileo Program between the "Galileo Joint Undertaking" (GJU) and the "National Remote Sensing Centre of China" (NRSCC). Based on the Sino-European Cooperation Agreement on Galileo program, China Galileo Industries (CGI), the prime contractor of the China’s involvement in Galileo programs was founded in December 2004. By April 2006, eleven cooperation projects within the Galileo framework had been signed between China and EU.
The Hongkong based South China Morning Post
South China Morning Post
The South China Morning Post , together with its Sunday edition, the Sunday Morning Post, is an English-language Hong Kong newspaper, published by the SCMP Group with a circulation of 104,000....
reported in January 2008 that China was unsatisfied with its role in the Galileo project and was to compete with Galileo in Asian market.
Description
BeiDou-1 is an experimental regional navigation system, which consists of four satellites (three working satellites and one backup satellite). The satellites themselves were based on the Chinese DFH-3Dong Fang Hong
Dong Fang Hong , meaning The East is Red, is a space satellite program for the People's Republic of China, which started in 1970. Satellites in this series were placed in either low Earth orbit or geostationary orbit and carried out a variety of purposes: testing, remote sensing,...
geostationary communications satellite and had a launch weight of 1,000 kilograms (2,200 pounds) each.
Unlike the American GPS, Russian GLONASS
GLONASS
GLONASS , acronym for Globalnaya navigatsionnaya sputnikovaya sistema or Global Navigation Satellite System, is a radio-based satellite navigation system operated for the Russian government by the Russian Space Forces...
, and European Galileo
Galileo positioning system
Galileo is a global navigation satellite system currently being built by the European Union and European Space Agency . The €20 billion project is named after the famous Italian astronomer Galileo Galilei...
systems, which use medium Earth orbit
Medium Earth Orbit
Medium Earth orbit , sometimes called intermediate circular orbit , is the region of space around the Earth above low Earth orbit and below geostationary orbit ....
(MEO) satellites, BeiDou-1 uses satellites in geostationary orbit
Geostationary orbit
A geostationary orbit is a geosynchronous orbit directly above the Earth's equator , with a period equal to the Earth's rotational period and an orbital eccentricity of approximately zero. An object in a geostationary orbit appears motionless, at a fixed position in the sky, to ground observers...
(GEO). This means that the system does not require a large constellation of satellites, but it also limits the coverage to areas on Earth where the satellites are visible. The area that can be serviced is from Logitude 70°E to 140°E, and from Latitude 5°N to 55°N.
Completion
The first satellite, BeiDou-1A was sent into its orbit on October 31, 2000. The second satellite, BeiDou-1B was successfully launched on December 21, 2000. The last satellite of the constellation, BeiDou-1C was carried into its orbit position on May 25, 2003, this launch also completed the construction of the experimental system.Position calculation
To calculate a position, the following procedure is used:- A signal is transmitted skyward by a remote terminal.
- Each of the geostationary satellites receive the signal.
- Each satellite sends the accurate time of when each received the signal to a ground station.
- The ground station calculates the longitude and latitude of the remote terminal, and determines the altitude from a relief map.
- The ground station sends the remote terminal's 3D position to the satellites.
- The satellites broadcast the calculated position to the remote terminal.
In 2007, the official Xinhua News Agency
Xinhua News Agency
The Xinhua News Agency is the official press agency of the government of the People's Republic of China and the biggest center for collecting information and press conferences in the PRC. It is the largest news agency in the PRC, ahead of the China News Service...
reported that the resolution of the BeiDou system was as high as 0.5 metres, considerably better than unaided GPS. With the existing user terminals appears that the calibrated accuracy is 20m (100m, uncalibrated).
Terminal
The terminal can communicate with the ground station by sending and receiving short messages.As of 2008, one BeiDou-1 terminal costs about RMB , almost 10 times the price of GPS counterpart. It's said that the reason why is the terminal so expensive is due to "using expensive imported Chips"，but China seemed to have found replacement and the price could lower to less than RMB. By the China High-Tech Fair ELEXCON 2009 (November 16–21, 2009) in Shenzhen
Shenzhen
Shenzhen is a major city in the south of Southern China's Guangdong Province, situated immediately north of Hong Kong. The area became China's first—and one of the most successful—Special Economic Zones...
, China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, a terminal solution costing no more than RMB was presented.
Applications
- Over 1000 BeiDou-1 terminals were used in the 2008 Sichuan earthquake2008 Sichuan earthquakeThe 2008 Sichuan earthquake or the Great Sichuan Earthquake was a deadly earthquake that measured at 8.0 Msand 7.9 Mw occurred at 14:28:01 CST...
, providing informations from the earthquake area. - As of October 2009, all Chinese border guards in YunnanYunnanYunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
are equipped with BeiDou-1 devices.
According to Sun Jiadong, chief designer of the navigation system, "Many organizations have been using our system for a while, and they like it very much."
Description
BeiDou-2 is not an extension to the existing BeiDou-1. The new system will be a constellation of 35 satellites, which include 5 geostationary orbit (GEO) satellites, for backward compatibility with BeiDou-1, and 30 non-GSO satellites (27 in Medium Earth Orbit (MEO) and 3 in Inclined GSO (IGSO)), that will offer complete coverage of the globe. There will be two levels of service provided; free service to civilians and licensed service to Chinese government and military users:- The free service will have a 10 meter location-tracking accuracy, will synchronize clocks with an accuracy of 10 ns, and measure speeds within 0.2 m/s.
- The licensed service will be more accurate than the free service, can be used for communication, and will supply information about the system status to the users.
Completion
It is planned that BeiDou-2 system will have more than 10 satellites by 2012 and may offer services for the Asia-Pacific region; The global navigation system should be finished by 2020.As of April 2011, eight satellites for BeiDou-2 have been launched. According to an official report , "the eighth Beidou satellite marks the completion of basic function of Beidou (Compass) Navigation Satellite System...collaborate with five navigation satellites...will be able to provide services to most regions in China after a period of orbiting running tests and system integration."
List of Satellites (as of April 10, 2011)
| Date | Launcher | Satellite | Orbit | Usable | System |
|---|---|---|---|---|---|
| 10/31/2000 | LM-3A Long March 3A The Long March 3A , also known as the Chang Zheng 3A, CZ-3A and LM-3A, is a Chinese orbital carrier rocket. It is a 3-stage rocket, and is usually used to place communications satellites and Beidou navigation satellites into geosynchronous transfer orbits.It has formed the basis of the Long March... |
BeiDou-1A | GEO Geostationary orbit A geostationary orbit is a geosynchronous orbit directly above the Earth's equator , with a period equal to the Earth's rotational period and an orbital eccentricity of approximately zero. An object in a geostationary orbit appears motionless, at a fixed position in the sky, to ground observers... 59°E |
? | BeiDou-1 |
| 12/21/2000 | LM-3A | BeiDou-1B | GEO 80°E | Yes | |
| 5/25/2003 | LM-3A | BeiDou-1C | GEO 110.5°E | Yes | |
| 2/3/2007 | LM-3A | BeiDou-1D | supersync orbit | No | |
| 4/14/2007 | LM-3A | Compass-M1 | MEO Medium Earth Orbit Medium Earth orbit , sometimes called intermediate circular orbit , is the region of space around the Earth above low Earth orbit and below geostationary orbit .... ~21,500 km |
Testing only | BeiDou-2 (Compass) |
| 4/15/2009 | LM-3C Long March 3C The Long March 3C , also known as the Chang Zheng 3C, CZ-3C and LM-3C, is a Chinese orbital carrier rocket. It is launched from Launch Complex 2 at the Xichang Satellite Launch Centre. A 3-stage rocket with two strapon liquid rocket boosters, it is a member of the Long March 3 rocket family, and... |
Compass-G2 | Drifting | No | |
| 1/17/2010 | LM-3C | Compass-G1 Compass-G1 Compass-G1, also known as Beidou-2 G1 is a Chinese navigation satellite which will become part of the Compass navigation system. It was launched in January 2010, and became the third Compass satellite to be launched after Compass-M1 and Compass-G2.... |
GEO 144.5°E | Yes | |
| 6/2/2010 | LM-3C | Compass-G3 | GEO 84°E | Yes | |
| 8/1/2010 | LM-3A | Compass-IGSO1 Compass-IGSO1 Compass-IGSO1, also known as Beidou-2 IGSO1 is a Chinese navigation satellite which will become part of the Compass navigation system. It was launched in July 2010, and became the fifth Compass satellite to be launched after Compass-M1, G2, G1, and G3.... |
118°E incl 55° | Yes | |
| 11/1/2010 | LM-3C | Compass-G4 | GEO 160°E | Yes | |
| 12/18/2010 | LM-3A | Compass-IGSO2 | 118°E incl 55° | Yes | |
| 04/10/2011 | LM-3A | Compass-IGSO3 | 118°E incl 55°, 200~35,991km | Yes | |
| 07/26/2011 | LM-3A | Compass-IGSO4 | 35698 x 35871 km incl 55.2 deg long: 78 to 110 deg E |
- Note: all dates are based on China Standard Time
External links
- Official website of BeiDou (Compass) Navigation Satellite System (in Chinese)
- BDstar Navigation
- BeiDou (Big Dipper) - GlobalSecurity.org
- Aviation International News
- BeiDou-1 - SinoDefence.com
- BeiDou-2 - SinoDefence.com