Beidou (satellite navigation)

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Beidou ( Chinese  北斗 , Pinyin Běidǒu  - " Big Bear ", abbreviation BDS ) is a Chinese satellite navigation system . The system can be used worldwide and is approved for civil users with an accuracy of ± 10 meters. Beidou, operated by the Xi'an Satellite Control Center of the People's Liberation Army's Strategic Combat Support Force , aims to reduce China's dependence on the US Global Positioning System (GPS). The civil services are marketed by the “Office for the Administration of the Chinese Satellite Navigation System ” (中国 卫星 导航 系统 管理 办公室 , Zhōngguó Wèixīng Dǎoháng Xìtǒng Guǎnlǐ Bàngōngshì ).

history

As early as the late 1970s, after the USA launched the first GPS satellite in 1978 , China was considering a commercial, satellite-based positioning system as part of its reform and opening-up policy . The project called "Lighthouse" (灯塔, Pinyin Dēngtǎ ) then came to nothing for various reasons, primarily because of China's lack of economic power. After the Soviet Union launched its first three GLONASS satellites on October 12, 1982 , and after US President Ronald Reagan opened the GPS system to civilians on September 16, 1983 as a result of the shooting down of Korean Air Lines flight 007 Announced its use, there was renewed interest in a satellite navigation system in China. Chen Fangyun from the Xi'an Satellite Control Center , in view of the then still limited economic opportunities in China, suggested, unlike in the USA and the Soviet Union, that only two geostationary communications satellites , which had been in development since 1975, and one ground station should be used: the ground station Send a signal via the satellites to the device at the user and this sent a response signal via the satellites back to the ground station, where the position of the user was determined from the different transit time delays in both satellites, which in turn was communicated to the user via the satellites. The working title of the project was " Dual Satellite Positioning System " ( 双星 定位 系统 , Shuāngxīng Dìngwèi Xìtǒng ).

On April 8, 1984, China placed a geostationary satellite in orbit for the first time, Dong Fang Hong 2-2 . A year later, in April 1985, Chen Fangyun publicly presented his concept at a conference. In March 1986, a preliminary application was made to develop the twin satellite positioning system, and a feasibility assessment meeting was held in April 1986. Three central questions emerged:

  • Why do we need this dual satellite positioning system when the GPS system already exists?
  • Is the system feasible with our technology level?
  • Can we finance it?

Apart from the advantage that the dual satellite positioning system, as it ran via communication satellites, in contrast to GPS, would also allow the transmission of short text messages, the meeting participants agreed after a heated discussion that from a geostrategic point of view and to ensure the security of the country, It is important to develop your own navigation system. 17 sub-projects were defined, Sun Jiadong ( 孙家栋 , * 1929) was appointed chief designer of the satellites, and Chen Fangyun - at the age of 70 - chief designer of the electronic systems. The double satellite project could not cover the whole earth - in theory 24 satellites were required for this - but two satellites were sufficient for the Chinese national territory.

The engineers began to raise research funds from various ministries, from the Ministry of Railways to the Forestry Administration. In 1989, the 13 companies and agencies involved in the project finally carried out their first practical tests with communications satellites that were already in orbit and the ground stations subordinate to the Xi'an satellite control center . It was possible to determine the position of a measuring team to an accuracy of 30 m. This was far better than had been hoped for. After the destruction caused by the USA in the Second Gulf War in 1991 with its GPS-guided missiles had deeply impressed those responsible in the People's Liberation Army , the Chinese government approved a start in 1993 on January 10, 1994, under the influence of the Yinhe incident in August 1993 The Chinese Academy of Space Technology submitted the plan for the construction of the Beidou-1 satellites, with which the "Beidou satellite navigation test system" should be set up.

Beidou satellite navigation trial system (Beidou 1)

Reception area of ​​the Beidou test system (2003)

The Beidou satellite navigation trial system ( 北斗 衛星 導航 試驗 系統  /  北斗 卫星 导航 试验 系统 , Běidǒu Wèixīng Dǎoháng Shìyàn Xìtǒng ) was still based on Chen Fangyun's original concept of two satellites in geostationary orbit. The name change from the bulky “ dual satellite positioning system” to “Beidou” was inspired by Liu Huan 's “ Hero's Song ” ( 好汉歌 ), which was very popular in 1994 , where the stars in the sky or the 108 heroes of Liang Shan who became human -Moor all orientate towards the Great Bear. The plan provided for a satellite to be stationed over the equator at 80 ° and 140 ° east longitude, so that an area between 70 ° and 140 ° east longitude and 5 ° to 55 ° north latitude could be covered, i.e. from the west , The north and east borders of China down to Ceylon. In the event that one of the two satellites failed, a reserve satellite was to be stationed between them at 110.5 ° east longitude, which, together with the other, could maintain the system.

The test system operated by the Office for Topography and Cartography at the General Staff under the direction of Brigadier General (from July 2008 Major General) Yuan Shuyou ( 袁树友 ) was designed to provide 540,000 users per hour with data, 150 of them simultaneously. The horizontal accuracy was 100 m, after setting up reference stations and using difference methods it was 20 m. Under optimal conditions, i. This means that if there was a line of sight to both satellites, a new location was determined every 5 seconds. Text messages with up to 120 characters (around six long sentences) could also be transmitted. Unlike later the satellites of the actual Beidou system, the experimental satellites did not yet have their own rubidium oscillators or hydrogen maser clocks on board, but instead obtained their time signal from the Xi'an satellite control center ; the accuracy of the timer was 20-100 nanoseconds. In addition, the system did not have the ability to measure the speed of the user, making it impossible to use it to control guided missiles.

On April 18, 2000, the International Telecommunication Union approved the People's Republic of China's application for a transmission frequency (2491.75 MHz) and the orbits of the satellites. The first two satellites, Beidou-1A and Beidou-1B, were launched from the Xichang cosmodrome on October 30 and December 20, 2000, respectively, followed by the Beidou-1C reserve satellite on May 24, 2003. On February 2, 2007, a fourth satellite, Beidou-1D, was launched, which after more than six years at 144 ° east longitude was to serve as a reserve for Beidou-1A (the ones based on the DFH-3 bus , without fuel, 1100 kg heavy satellites had a regular lifespan of five years). However, this satellite had a problem with the southern solar panel shortly after launch , which resulted in it no longer being able to be brought into correct orbit. After two months of remote maintenance by the Research Institute 513 of the Chinese Academy for Space Technology in Yantai , it was finally possible on April 11, 2007 to place the satellite in the correct orbit, where it worked properly from then on.

Serial
No.		 Start (UTC) carrier
rocket		 Satel-
liten-
name		 orbit Position
(east
longitude)		 Catalog
No.
( AFSC )		 COSPAR
name		 comment
Beidou-1
1 Oct 30, 2000 CZ-3A 1A GEO 140 ° 26599 2000-069A out of service since 2011
2 Dec 20, 2000 CZ-3A 1B GEO 80 ° 26643 2000-082A out of service since 2011
3 May 24, 2003 CZ-3A 1C GEO 111 ° 27813 2003-021A out of service since 2012
4th 0Feb 2, 2007 CZ-3A 1D GEO 144 ° 30323 2007-003A out of service since 2009

While in the American Global Positioning System the satellites circling in various orbits constantly transmit their current position, from which the receiver then calculates its own position, communication in both directions took place in the Beidou test system. This required a transmitter in the user's end device, which made said devices relatively large, heavy and expensive, and they also had a high power consumption. In 2008, a device manufactured by Space Star Weltraumtechnologie GmbH ( 航天 恒星 空间 技术 应用 有限公司 , a subsidiary of the Chinese Academy of Space Technology through China Spacesat Corporation ) cost 20,000 yuan, almost ten times the price of a GPS receiver. Back then, a large bowl of beef noodle soup cost 3.50 yuan; Although the Beidou system, which went into operation in December 2003, was released for Chinese civilian users in April 2004, it was primarily used by the fisheries authorities of the Ministry of Agriculture , the military, border guards and the fire brigade, which was then subordinate to the People's Armed Police . In the latter application areas, the two-way principle was a major disadvantage: if a patrol in a mountain valley lost visual contact with the satellite during the relatively long-term position calculation, there was no correct position determination.

Nevertheless, the Beidou system proved to be extremely useful in the severe earthquake in Sichuan in 2008 . More than 1000 devices were issued to the rescue teams. The Xi'an satellite control center used the Chinese weather and earth observation satellites to get an overview of the destruction in the remote villages from space, guided the rescue teams via Beidou to the worst affected locations, and these then transmitted via the short messages Function of the system detailed reports on the situation on site.

Asia Pacific (Beidou 2)

Beidou 2 reception area (2012)

Due to the need to maintain line of sight with two satellites that are 60 ° apart and located deep on the southern horizon, the Beidou test system was not really suitable for military purposes, especially in the mountainous terrain of southwest China. In addition, with Chen Fangyun's system, the position calculation took place in the central ground station. In the event of an armed conflict, it would have been enough to shut down the Xi'an satellite control center and the entire system would have been paralyzed. Already at the beginning of 2000, before the World Radio Conference in Istanbul (May 8 to June 2) and before the first satellite of the test system was launched, the International Telecommunication Union had applied for frequencies and orbits for a global passive positioning system that the user did not have Transmitters required more and, in addition to geostationary, also used satellites in inclined orbits, just like GPS or GLONASS . On April 18, 2000, said frequencies and orbits were approved by the ITU.

Now you had seven years to send the first satellite into space, then the unused frequencies would expire. After the trial system was successfully put into operation in December 2003, the question arose as to whether the final system wanted to build a global network from the beginning, or whether it should proceed gradually. After a controversial discussion, the decision was made for the latter: first to cover the Asia-Pacific region, then the whole world. In 2004, the project known as “Beidou 2” ( 北斗 二号 , Běidǒu Èr Hào ) for the Asia-Pacific region was approved by the Chinese government.

Given the deadline set by the International Telecommunication Union, that was very late. It normally takes five years to develop a satellite. With numerous overtime succeeded then but still, beginning of April 2007 the first, for a medium earth orbit (MEO) with an orbital inclination of 57 ° imaginary satellite together with a carrier rocket of the type Changzheng 3A for Xichang Satellite Launch Center to bring. The rocket was assembled, the satellite mounted, and during the third main inspection, shortly before take-off, it was noticed that the signal sent by the satellite's transponder was unstable. This was a core component of the satellite. A major repair ran the risk of not being able to meet the ITU deadline, and if you didn't fix the problem, you risked the Beidou users not receiving a signal. In addition, the manufacturer of the transponder was located in Shanghai and could not be reached within the time limit of three days set by the cosmodrome. The decision was then made to set up a laboratory in Chengdu , to remove the transponder from the launch tower at a height of 50 m and to take it to the provincial capital in an adventurous journey over winding mountain roads. The launch finally took place on April 14, 2007 at 4:11 am local time, and on April 17, at 8 p.m. Beijing time, four hours before the deadline, the satellite sent its first signal.

In addition to the political conditions at that time and the chronic underfunding of the project, the reason for the chaos was that two competing concepts for Beidou 2 had been in circulation since 2000, which were again revised several times. One concept, called Compass-GEO for international use , envisaged four satellites in a geostationary orbit (GEO) and nine satellites in a geosynchronous orbit inclined by 50 ° (IGSO). The other concept, Compass-GEO & MEO , envisaged four geostationary satellites and 12 satellites in a central orbit inclined at 55 °. In the end, all three types of orbits were used. When the Beidou-2 system, i.e. the Asia-Pacific region, was officially put into operation on December 27, 2012, it comprised 5 satellites in geostationary orbit, 5 satellites in inclined geosynchronous orbit and 4 satellites in a mean earth orbit of around 21,500 km altitude, so a total of 14 active satellites. The Beidou-2 G2 geostationary satellite, launched on April 14, 2009, began to drift west a few months after reaching its position, then back east again, and was not part of the system. The first satellite, launched in April 2007, was only used as a test satellite and was not included in the Beidou-2 system when it was officially commissioned in 2012.

Serial
No.		 Start (UTC) carrier
rocket		 Satel-
liten-
name		 PRN orbit Position
(east
longitude)		 Inkli-
nation		 Catalog
No.
( AFSC )		 COSPAR
name		 comment
Beidou-2
1 Apr 13, 2007 CZ-3A M1 C30 MEO - 57 ° 31115 2007-011A Test satellite
2 Apr 14, 2009 CZ-3C G2 - GEO drifts 1 ° 34779 2009-018A never in operation
3 Jan. 16, 2010 CZ-3C G1 C01 GEO 140 ° 2 ° 36287 2010-001A
4th 0June 2, 2010 CZ-3C G3 C03 GEO 110 ° 2 ° 36590 2010-024A
5 July 31, 2010 CZ-3A IGSO1 C06 IGSO 118 ° 55 ° 36828 2010-036A
6th Oct 31, 2010 CZ-3C G4 C04 GEO 160 ° 1 ° 37210 2010-057A
7th Dec 17, 2010 CZ-3A IGSO2 C07 IGSO 120 ° 55 ° 37256 2010-068A
8th 0Apr 9, 2011 CZ-3A IGSO3 C08 IGSO 118 ° 55 ° 37384 2011-013A
9 July 26, 2011 CZ-3A IGSO4 C09 IGSO 93 ° 55 ° 37763 2011-038A
10 0Dec 1, 2011 CZ-3A IGSO5 C10 IGSO 95 ° 55 ° 37948 2011-073A
11 Feb 24, 2012 CZ-3C G5 C05 GEO 59 ° 1 ° 38091 2012-008A
12 Apr 29, 2012 CZ-3B M3 C11 MEO - 56 ° 38250 2012-018A
13 M4 C12 MEO - 56 ° 38251 2012-018B
14th Sep 18 2012 CZ-3B / E M5 C13 MEO - 56 ° 38774 2012-050A
15th M6 C14 MEO - 56 ° 38775 2012-050B
16 Oct 25, 2012 CZ-3C G6 C02 GEO 80 ° 1 ° 38953 2012-059A

At the time when regular operations began, the Chinese government had spent a total of more than 20 billion yuan on the Beidou satellite navigation system since the project began in 1994, most recently from the Fund for National Major Scientific and Technical Projects . On the other hand, various companies had already made a total of 120 billion yuan in sales in the one year since the interface standards were published on December 27, 2011 with the manufacture of end devices etc., although this figure is due to the relatively high price of said devices. At the same time, the office for the administration of the Chinese satellite navigation system under the direction of Ran Chengqi ( 冉 承 其 ), who has been running the system since the start of test operation on December 27, 2011, initiated model projects with various ministries and authorities to make the system known close. For example, in cooperation with the Ministry of Transport, Beidou receivers were installed in 100,000 trucks to avoid wandering and save fuel. A marine navigation system for the Pearl River Delta was set up in cooperation with Guangdong Province , and the Guangzhou City Government installed Beidou terminals in more than 10,000 public service vehicles. Since Beidou 2 had taken over from Beidou 1 the possibility of sending short messages - for a fee - and the automatic location reporting of the recipient, the use of company cars for private journeys, a phenomenon that was widespread at the time, could be greatly reduced.

Another important customer for Beidou devices was and is the People's Liberation Army . In 2014, for example, all regiments of the Army and all ships of the Navy were equipped with terminals, in the case of special units such as tele-spies or airborne troops down to the group level . As far as the accuracy of Beidou 2 is concerned, on December 27, 2012, civil users between 55 ° and 180 ° east longitude and 55 ° south latitude and 55 ° north latitude were guaranteed the following free minimum standards:

  • Horizontal location: 10 m
  • Vertical positioning: 10 m
  • Speed ​​determination: 20 cm / s or 0.72 km / h
  • Timer: 50 nanoseconds

The signals for the free civil service are sent on 1561.098 MHz, with a bandwidth of 4.092 MHz, and since 2013 also on 1207.14 MHz with a bandwidth of 24 MHz. In addition, there is a third frequency - 1268.52 MHz with a bandwidth of 24 MHz - for military purposes, where the accuracy of the location was already 2.5 m in 2014. There are also paid services on the first two frequencies. In addition to the ability to send short messages and automatic location reporting, the military and civilian services, which are subject to a fee, offer greater accuracy - NASA estimated about 6 m horizontally in 2015 - and are interference-free. The Beidou-2 satellites manufactured by Dong Fang Hong Satellites GmbH, a subsidiary of the Chinese Academy of Space Technology, are based on the DFH-3 satellite bus and have an empty weight of 1180 kg (MEO), 1280 kg (IGSO) and 1380– 1550 kg (GEO). They have a lifespan of eight years. The satellites have broadband antennas for the three navigation signal frequencies and a laser retroreflector for satellite laser ranging . The five geostationary satellites also have an antenna for transmitting text messages in the C-band (3950–5800 MHz).

Beidou-3 trial system

After the unpleasant events when purchasing the atomic clocks for the Beidou-2 satellites in Switzerland (see below), those responsible in China decided in 2005 to manufacture the timers for the global version of the satellite navigation system in their own country. A working group was set up at the China Aerospace Science and Technology Corporation , the China Aerospace Science and Industry Corporation and at the Shanghai Astronomical Observatory to deal with the problem. The CASC and the research institute 203 of CASIC were assigned the development of satellite - compatible rubidium oscillators , internationally known as the Rubidium Atomic Frequency Standard or RAFS . The first hydrogen maser clocks were developed at the Shanghai Observatory as early as the mid-1970s , and the laboratory there was for time and frequency generators and is the only facility in China where hydrogen maser watches are mass-produced. Therefore, the order for these watches went there.

Active hydrogen masers are relatively complex and heavy, up to 90 kg, which is why only passive hydrogen masers ( Passive Hydrogen Masers or PHM ) are possible for use on satellites , which are less precise but much lighter (the PHM on board the Galileo satellites weighs only 18 kg). After two years of development, both the rubidium oscillators and the hydrogen masers were ready for use, the latter with an intrinsic frequency drift of 8 × 10 −15 per day, which was not as good as with the observatory's active measles - the frequency drift is included there 2 × 10 −15 per day - but good enough for the purpose. This meant that when the Beidou system was expanded in 2007, it was completely independent of foreign technology.

Frequencies used by navigation satellites (COMPASS = Beidou)

After the approval for the third expansion stage of the satellite navigation system was granted in 2009, a Beidou-3 test system ( 北斗 三號 試驗 系統  /  北斗 三号 试验 系统 , Běidǒu Sān Hào Shìyàn Xìtǒng ) was initially implemented, similar to the Beidou-1 system. with five test satellites launched in 2015/16. On the one hand, these test satellites sent the old free Beidou 2 signals at 1561.098 MHz with a bandwidth of 4.092 MHz, called the "B1 band" by the engineers, and on the other hand the signals intended for Beidou 3 at 1207.14 MHz with a Bandwidth of 24 MHz (E5 band) for public use and chargeable special services, 1268.52 MHz with a bandwidth of 24 MHz (B3 band) for military purposes and 1575.42 MHz with 32.736 MHz bandwidth (L1 band) for public use Use and paid special services. The latter frequency overlaps with signals from GPS and European Galileo satellites. The Beidou 3 IGSO 2-S test satellite launched on September 29, 2015 and manufactured by the Chinese Academy of Space Technology, which was placed in a geosynchronous orbit inclined at 55 ° to the equator , was the first to feature a hydrogen maser watch in Chinese space travel for use.

Beidou 3

On December 27, 2018, exactly six years to the day after the activation of Beidou 2, the Beidou 3 basic version ( 北斗 三號 基本 系統  /  北斗 三号基本系统 , Běidǒu Sān Hào Jīběn Xìtǒng ) was released for general use . At the time, there were 15 Beidou-2 satellites and 18 Beidou-3 satellites launched on November 5, 2017, which now operated together. Theoretically, China offered the Beidou services to the entire world from that day on, but due to the position of the satellites, initially only the countries of Africa and Asia were able to use the system meaningfully. Ran Chengqi, the head of the office for the administration of the Chinese satellite navigation system, was able to guarantee the following free minimum standards for civil customers:

  • Horizontal location: 10 m
  • Vertical positioning: 10 m
  • Speed ​​determination: 20 cm / s or 0.72 km / h
  • Timer: 20 nanoseconds
  • Usable: 95% of the day

The following paid services are offered:

  • Short messages with up to 1000 characters
  • Sending photos
  • Voice communication

Since additional ground stations for telemetry, orbit tracking and control of the satellites had been set up in the ASEAN countries since 2013 (see below), the accuracy of the location determination in the horizontal and vertical directions was 5 m each. In the course of 2019, a total of 9 satellites were launched into space with six rocket launches, completing the expansion of the core constellation in December of that year. At that point in time, a year after the activation of the Beidou 3 basic version, there were still blind spots in North and South America and in the East Pacific, where sometimes no satellite could be seen, in the areas well covered by the system, i.e. Europe , Africa and Asia, however, location accuracy has been increased to better than 5 m everywhere, both horizontally and vertically. With the launch on June 23, 2020, all planned satellites are now in space. From October 2020 - apart from a few reserve satellites - the Beidou-2 satellites will be gradually taken off the grid when they reach their age limit.

By 2035, when a uniform national positioning, navigation and timing system with Beidou as the core is to go into operation, the number of active satellites in the system is to be kept at 35 - 5 in geostationary orbits (GEO), 27 in medium orbits (MEO ) and 3 in inclined geosynchronous orbits (IGSO). The geostationary satellites should ideally be stationed at 57.75 °, 80 °, 110.5 °, 140 ° and 160 ° east longitude. The MEO satellites are distributed over three orbit planes inclined by 55 ° , the intersection of which with the equator is 120 ° apart. Since the satellites launched in 2010 have a regular life expectancy of 15 years, this often requires the launch of new satellites. The satellites in the current network are partly based on the DFH-3B bus , which was developed for the Beidou-2 system from 2008 , and partly are custom-made by the Chinese Academy for Space Technology and the Shanghai Engineering Office for Microsatellites ( 上海 微小 卫星 工程 中心 or Shanghai Engineering Center for Microsatellites , SECM for short ), a non-profit association founded by the Chinese Academy of Sciences and the Shanghai City Government in December 2003. The unladen weight of the Beidou-3 satellites is around 1000 kg (MEO) or 3000 kg (IGSO and GEO).

The Beidou-3 satellites can communicate with each other and form a network in space that is independent of the network of ground stations. The Xi'an satellite control center responsible for the operation of the satellites only needs to issue a command to a single satellite, which then transmits said command to all other satellites in the constellation. In the same way, the individual satellites first transmit their telemetry data to a satellite, which then transmits them collectively to Xi'an. In this way, a large amount of resources are saved for the ground stations, which have to carry out more than 200 orbital monitoring operations per day (as of 2019). On July 31, 2020, the Beidou 3 satellite navigation system was officially released for worldwide use.

Current satellite list

Serial
No.		 Start (UTC) carrier
rocket		 Satel-
liten-
name		 PRN orbit Position
(east
longitude)		 Inkli-
nation		 Catalog
No.
( AFSC )		 COSPAR
name		 comment
Beidou-2
1 Apr 13, 2007 CZ-3A M1 - MEO - 57 ° 31115 2007-011A Out of service
2 Apr 14, 2009 CZ-3C G2 - GEO drifts 1 ° 34779 2009-018A Out of service
3 Jan. 16, 2010 CZ-3C G1 C01 GEO 140 ° 2 ° 36287 2010-001A
4th 0June 2, 2010 CZ-3C G3 - GEO 97 ° 2 ° 36590 2010-024A Out of service
5 July 31, 2010 CZ-3A IGSO1 C06 IGSO 118 ° 55 ° 36828 2010-036A
6th Oct 31, 2010 CZ-3C G4 C04 GEO 160 ° 1 ° 37210 2010-057A
7th Dec 17, 2010 CZ-3A IGSO2 C07 IGSO 118 ° 55 ° 37256 2010-068A
8th 0Apr 9, 2011 CZ-3A IGSO3 C08 IGSO 118 ° 56 ° 37384 2011-013A
9 July 26, 2011 CZ-3A IGSO4 C09 IGSO 95 ° 55 ° 37763 2011-038A
10 0Dec 1, 2011 CZ-3A IGSO5 C10 IGSO 95 ° 55 ° 37948 2011-073A
11 Feb 24, 2012 CZ-3C G5 C05 GEO 59 ° 1 ° 38091 2012-008A
12 Apr 29, 2012 CZ-3B M3 C11 MEO - 55 ° 38250 2012-018A
13 M4 C12 MEO - 55 ° 38251 2012-018B
14th Sep 18 2012 CZ-3B / E M5 - MEO - 55 ° 38774 2012-050A Out of service
15th M6 C14 MEO - 55 ° 38775 2012-050B
16 Oct 25, 2012 CZ-3C G6 C02 GEO 80 ° 1 ° 38953 2012-059A
22nd 29 Mar 2016 CZ-3A IGSO6 C13 IGSO 96 ° 56 ° 41434 2016-021A
23 June 12, 2016 CZ-3C G7 C03 GEO 110 ° 1 ° 41586 2016-037A
32 0July 9, 2018 CZ-3A IGSO7 C16 IGSO 112 ° 55 ° 43539 2018-057A
45 17th May 2019 CZ-3C G8 C18 GEO 80 ° 1 ° 44231 2019-027A
Beidou-3
17th 30th Mar 2015 CZ-3C / YZ-1 IGSO 1-S C31 IGSO 98 ° 55 ° 40549 2015-019A Test satellite
18th July 25, 2015 CZ-3B / YZ-1 M1-S C57 MEO - 55 ° 40748 2015-037A Test satellite
19th M2-S C58 MEO - 55 ° 40749 2015-037B Test satellite
20th 29 Sep 2015 CZ-3B IGSO 2-S C18 IGSO 95 ° 55 ° 40938 2015-053A Test satellite
21st 0Feb. 1, 2016 CZ-3C / YZ-1 M3-S - MEO - 55 ° 41315 2016-006A Test satellite
24 0Nov 5, 2017 CZ-3B / YZ-1 3 M1 C19 MEO - 55 ° 43001 2017-069A
25th 3 M2 C20 MEO - 55 ° 43002 2017-069B
26th Jan. 11, 2018 CZ-3B / YZ-1 3 M3 C27 MEO - 55 ° 43107 2018-003A
27 3 M4 C28 MEO - 55 ° 43108 2018-003B
28 Feb 12, 2018 CZ-3B / YZ-1 3 M5 C22 MEO - 55 ° 43207 2018-018A
29 3 M6 C21 MEO - 55 ° 43208 2018-018B
30th 29 Mar 2018 CZ-3B / YZ-1 3 M7 C29 MEO - 55 ° 43245 2018-029A
31 3 M8 C30 MEO - 55 ° 43246 2018-029B
33 29th July 2018 CZ-3B / YZ-1 3 M9 C23 MEO - 55 ° 43581 2018-062A
34 3 M10 C24 MEO - 55 ° 43582 2018-062B
35 24 Aug 2018 CZ-3B / YZ-1 3 M11 C26 MEO - 55 ° 43602 2018-067A
36 3 M12 C25 MEO - 55 ° 43603 2018-067B
37 19 Sep 2018 CZ-3B / YZ-1 3 M13 C32 MEO - 55 ° 43622 2018-072A
38 3 M14 C33 MEO - 55 ° 43623 2018-072B
39 Oct 15, 2018 CZ-3B / YZ-1 3 M15 C35 MEO - 55 ° 43647 2018-078A
40 3 M16 C34 MEO - 55 ° 43648 2018-078B
41 0Nov 1, 2018 CZ-3B / G2 3 G1 C59 GEO 145 ° 2 ° 43683 2018-085A
42 Nov 18, 2018 CZ-3B / YZ-1 3 M17 C36 MEO - 55 ° 43706 2018-093A
43 3 M18 C37 MEO - 55 ° 43707 2018-093B
44 April 20, 2019 CZ-3B / G2 IGSO-1Q C38 IGSO 107 ° 55 ° 44204 2019-023A
46 June 24, 2019 CZ-3B / G2 IGSO-2 C39 IGSO 98 ° 55 ° 44337 2019-035A
47 22 Sep 2019 CZ-3B / YZ-1 3 M23 C46 MEO - 55 ° 44542 2019-061A
48 3 M24 C45 MEO - 55 ° 44543 2019-061B
49 0Nov 4, 2019 CZ-3B / G2 IGSO-3 C40 IGSO 125 ° 59 ° 44709 2019-073A
50 23 Nov 2019 CZ-3B / YZ-1 3 M21 C44 MEO - 55 ° 44793 2019-078A
51 3 M22 C43 MEO - 55 ° 44794 2019-078B
52 16 Dec 2019 CZ-3B / YZ-1 3 M19 C41 MEO - 55 ° 44864 2019-090A
53 3 M20 C42 MEO - 55 ° 44865 2019-090B
54 09 Mar 2020 CZ-3B / G2 3 G2 C60 GEO 80 ° 3 ° 45344 2020-017A
55 June 23, 2020 CZ-3B / G2 3 G3 C61 GEO 110.5 ° 3 ° 45807 2020-040A

As of July 28, 2020

Recipient support

The Samsung S5, S6, S7, S8, S9 series, the XCover 4 and the Nokia 8 are listed as BDS-capable.

The OnePlus 5T, OnePlus 6, OnePlus 6T, OnePlus 7 and OnePlus 7Pro smartphones are BDS-capable. The Xiaomi smartphone Redmi Note 5 supports GLONASS as well as Beidou. The module manufacturer u-blox offers embedded modules (series M8030) that can receive Beidou in addition to other satellite navigation systems.

use

The People's Republic of China uses the navigation system and the applications it enables for its international relations, military and economic policy. Even before the global Beidou-3 service went online, the service was deployed in over 70 countries and districts selected by the Chinese government. Examples of the applications with a political and economic background are the planning and control of inland navigation in Myanmar and the urban modernization measures and smart tourism in Brunei.

After the initial experience with Beidou 1, China originally planned to join the European Galileo system . On 28 May 2003, the issued Council of the European Union of the European Commission's approval to enter into formal negotiations with China. After an initial meeting in Brussels on April 23, 2003, another meeting took place in Beijing on September 18, 2003, with François Lamoureux (1946–2006), head of the European Commission's Directorate-General for Energy and Transport , and Shi Dinghuan ( 石 定 环 , * 1943), Secretary General of the Ministry of Science and Technology of the People's Republic of China, signed a draft contract in which cooperation on satellite-based navigation and time signals was agreed, both in science and technology as well as in production, services and marketing, also joint Standards for the frequencies used and the certification. China agreed to contribute 230 million euros to the Galileo project, about a fifth of the then expected cost of 1.1 billion euros for a network with 30 satellites.

The contract was only finally signed at the EU-China summit on October 30, 2003, but on September 19 the “China-Europe Global Navigation Satellite System Technical Training and Co-operation Center” was opened in the Beijing high-tech district of Zhongguancun ) was inaugurated, in which all Chinese Galileo activities were to be bundled. The center was jointly operated by the Ministry of Science and Technology, the National Center for Remote Sensing ( 国家 遥感 中心 ), the European Commission and the ESA , and was intended to serve as a platform where European companies could come together with Chinese partners to jointly develop applications for the To develop the Galileo system. At the time, the European arms industry in particular hoped to do business with China. It was assumed that if a country opted for Galileo, it would design military systems such as guided missiles etc. in such a way that they would be compatible with Galileo. On the other hand, there were politicians in the EU who saw China's participation in Galileo as an attempt to undermine Europe's strategic partnership with the USA. A British expert believed that China wanted to adopt European technology and use it in the military applications of its own Beidou system, something that was difficult to stop China from doing. In addition, Taiwan and the US put pressure on the EU and other states to reduce cooperation with China from the start.

The pressure had an effect. After the Chinese government approved the Beidou-2 project for the Asia-Pacific region in 2004, the People's Republic entered into negotiations with the Swiss company Spectratime (then Temex Time ) to purchase rubidium oscillators as timers for the satellites. The negotiations went well at first, until Spectratime suddenly no longer wanted to sell the atomic clocks to China. In 2006 a contract was signed according to which Spectratime China would supply 20 old oscillators that the company had in stock since the mid-1990s from a canceled order from Russia. However, the incident led China to believe that foreigners cannot be relied on. In December 2007, the People's Republic de facto withdrew from the Galileo project. The partnership was officially ended in 2010.

The cooperation with the Asian countries works much better. At a conference of scientists and engineers in Beijing on January 19, 2013, Wan Gang , then Minister of Science and Technology , announced that China would be joining forces with the Association of Southeast Asian Nations ( 中国 东盟科技 伙伴 计划 ) wanted to set up ground stations for the Beidou system in each member country of the association. As a result, the accuracy of the position determination for public use in the Asia-Pacific region could be increased from 10 m to 5 m by 2018. As it is with the help of the tracking stations and a software developed by Zhao Qile ( 赵 齐 乐 , * 1975) and his colleagues at the Research Institute for the Technology of Satellite-Aided Navigation and Position Determination (卫星 导航 定位 技术 研究 中心) at Wuhan University called Position And Navigation Data Analysis (PANDA) it is possible to determine the position of the satellites with a precision of a few millimeters, in the Asia-Pacific region it is technically feasible to determine the position while stationary to within a few centimeters, if the user moves, then in the decimeter range. This would enable satellite support for the so-called “ vehicle ad hoc network ” ( 车 联网 ), for autonomous driving and automatic parking. Since the Beidou system, which is accessible to civil users, is superior to the American standard positioning service in terms of precision, China sees a promising field of business in this area.

First of all, however, this concerns applications in agriculture. In Tunis , where the Office for the Management of the Chinese Satellite Navigation System opened a Sino-Arab Beidou Center on April 10, 2018 together with the Arab Organization for Information and Communication Technologies (AICTO) in the Elgazala Technopark, a meeting on April 1 / 2. April 2019 presented a self-propelled tractor. On March 10th that year, engineers from UniStrong AG from Beijing installed an electric steering wheel and a Beidou device in a tractor from the Majaz al Bab agricultural college within a few hours, which enabled the tractor to maintain a precise course without human intervention. He circled stones kept in his way at a close distance and then returned to his old course. A similar system from the Rongwei Electronics Technology Development Company ( 成都 蓉 威 电子 技术 开发 公司 ) from Chengdu was used for the spring sowing 2020 in Xinjiang , where the fields are particularly suitable for machining due to the often flat terrain . By sowing in precise rows, which are covered with foil in the same operation, it is hoped - in addition to making work easier for the farmers - to be able to increase the harvest yield by 7% to 15%.

In Pakistan, however, Beidou is used primarily for military purposes. In 2011 a delegation of Pakistan's nuclear forces ( Pakistan Strategic Forces Command ) visited the Office for Topography, Cartography and Navigation ( 总参谋部 测绘 导航 局 , now the Office for satellite-based operations), which was part of the General Staff Operations Command ( 中国人民解放军 总参谋部 作战 部 ) Navigation of the Joint General Staff at the Central Military Commission ), where an agreement was signed giving Pakistan access to their specially secured signals in return for servicing the Beidou satellites from the Karachi ground station of the Space and Upper Atmosphere Research Commission . Via the ground station originally built for the Paksat 1R communications satellite , the Pakistani army was also able to use the position feedback and the short message service of the Beidou system. The final contract between SUPARCO and the office for the administration of the Chinese satellite navigation system took place at the end of September 2012 in Karachi.

See also

Web links

Individual evidence

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