BeiDou: what is it in a smartphone. Beidou satellite system Which smartphones support Beidou

When buying a smartphone or studying its capabilities, you come across information that this device supports Beidou or BDS.

In this regard, many become interested in what system we are talking about, what it is, and what new functions and capabilities it offers.

What is Beidou?

Beidou is a new navigation system developed in China. It was named after the constellation Ursa Major, or rather its Chinese name. Beidou was launched in 2000. This system is a direct analogue and competitor of the GPS system developed in the USA and the Russian GLONASS system. It is also used for both the armed forces and ordinary civilian users.

Title and relevance

To draw conclusions about the relevance of Beidou for smartphone owners outside of China, you need to know about the technology's coverage area, as well as the number of satellites and ground base stations that provide navigation support.

Currently, Beidou operates in limited functionality mode, since stable satellite signal reception has only been achieved over China. Over the rest of the land the signal is less stable, which is explained by the insufficient number of orbital devices. Chinese developers promise complete coverage of the entire globe by 2020. At the beginning of 2017, a stable signal from six satellites was observed over the European part of Russia, as well as over eastern Europe, and one base station was successfully built and launched in Belgium.

Of course, China’s creation of its own navigation system gives this country a number of advantages both in foreign policy and in general civil spheres. This country plans to significantly increase the number of operating satellites, and in number they will significantly exceed the existing GLONASS and GPS satellites.

Beidou in smartphones

But let’s leave aside discussions about the military sphere and world domination, let’s talk about ordinary smartphone owners. It is obvious that Chinese citizens will have access to the most stable navigation system in the near future. Due to the large number of satellites, access to geodata must be open even in difficult conditions, such as in tunnels.

What steps are smartphone manufacturers taking in this direction? Most Chinese brands provide parallel operation of Beidou, GPS and GLONASS. Other companies divide gadgets based on the market to which they will be supplied.

The ability of a smartphone to use the Beidou system is welcome, but not required. Of course, it's nice to have an additional navigation system, but at the moment it's unlikely to be useful to users outside of China.

History of the BeiDou GNSS

The Chinese navigation system is called Beidou Series BNTS (BeidouNavigationTestSatellite). The name of the devices comes from the Chinese name for the constellation Ursa Major.

The idea of ​​creating a Chinese regional navigation system of two spacecraft in geostationary orbit was proposed in 1983 by Chen Fangyun. The concept was experimentally tested in 1989. The experiment was carried out on the basis of two DFH-2/2A spacecraft in orbit.

According to the Chinese side, tests have shown that the accuracy that can be achieved using a system of two geostationary spacecraft is comparable to the accuracy provided by the GPS system. This statement seems highly controversial. Apparently, when comparing accuracy, we are talking about a system that includes not only GEO spacecraft, but also several ultra-long-wave ground stations. Together, they form a single network of radio navigation reference points and make it possible to create a difference-range radio navigation system. The difference between such a system and, for example, GPS or GLONASS is the impossibility of using speed measurements. The accuracy of determining the consumer’s coordinates in such a system is, in principle, comparable to the accuracy provided by the “civilian” signal of the GPS system in the selective access mode, provided that the current position of the navigation spacecraft on the GSO is known with high accuracy.

In 1993, the Beidou program was officially launched. The design of the device uses the same base unit as that of the DFH-3 communications satellite. The spacecraft is built on the basis of the DFH-3 geostationary communications platform.

China began independently developing satellite navigation systems in 1994. Before that, such scientific and technical inventions were only able to be created in the USA, Russia and Europe.

In 2000, the design of the second generation of a navigation system began, which will include a larger number of satellites and serve not only the territory of the PRC, but also other areas.

On December 15, 2003, China's first-generation Beidou system was put into operation, allowing the country to become one of the top three countries with its own satellite navigation system.

The creation of the China Global Navigation System was announced in 2006. Currently, China has launched five navigation satellites into Earth orbit. They allow you to navigate only in some areas of the country. An additional 30 satellites should provide Beidou with worldwide coverage. The start date of the system on a global scale is still unknown.

In November 2017, the Sino-American Joint Statement on the Compatibility and Complementarity of Beidou and GPS was signed.

In November 2018, an agreement was concluded between the Governments of the Russian Federation and the People's Republic of China on cooperation in the use of the GLONASS and Beidou global navigation satellite systems for peaceful purposes.

The system of ground-based functional additions includes 155 base stations and 2,400 regional stations deployed in the PRC.

In 2018, the deployment of the core infrastructure of the iGMAS monitoring and assessment system, consisting of 24 ground stations and various processing and analysis centers, was completed, resulting in improved quality of Beidou-2 services, incl. Positioning accuracy in the service area has been improved to better than 5 m.

On August 2, 2019, a law was signed on the ratification of the Russian-Chinese intergovernmental Agreement on cooperation in the field of application of the GLONASS and Beidou global navigation satellite systems.

The agreement was signed to ensure compatibility and complementarity of navigation satellite systems - Russian GLONASS and Chinese Beidou. In particular, the parties pledged to place measuring stations of the GLONASS system in China and the Beidou system in Russia.

Moscow and Beijing also agreed to develop and produce civil navigation equipment using these systems.

Operating principle of BeiDou GNSS

The Beidou spacecraft is controlled from the Satellite Control Center in Xi'an (Shanxi Province). China's own regional navigation system for Southeast Asia and the Pacific based on the Beidou (Big Dipper) satellites (Compass) is under deployment and is planned to be transformed into a limited-capability global navigation system with space segment of 25 spacecraft.

The system should include four geostationary satellites, 12 spacecraft in inclined geosynchronous orbits and nine spacecraft in circular orbits at an altitude of 22,000 km.

Chinese representatives also noted that issues regarding frequency ranges have yet to be resolved with the Russian, American and European sides, which also own satellite navigation constellations. For BeiDou-2 satellites in geostationary orbit, the reserved positions are 58.75°, 80°, 110.5° and 140° East. The system is registered with the International Telecommunication Union under the designation “Compass”. The first of four geostationary satellites, Beidou-2, was launched on April 12, 2007. These devices will be compatible with the three already launched Beidou-1.

By 2015, China plans to complete the creation of its own global navigation system, Xinhua reports. A source at the China Aerospace Science and Technology Corporation said that 30 satellites should be launched into orbit.

Composition and structure of BeiDou GNSS

The system covers an area in the latitude range from approximately 5 to 55 degrees north latitude. and in longitude from approximately 70 to 140 degrees east. An interesting feature of all three satellites is that they are in geostationary orbits, unlike GPS and GLONASS satellites, which are in medium altitude orbits. This fact makes it possible to provide a fairly large coverage area using only two satellites. The ground system includes a central control station and three radar stations.

The system provides a location accuracy of 100 meters and can operate simultaneously with 150 terminals. First, the central station sends a signal to the user through two satellites. When the user's terminal receives a signal from one of the satellites, it sends it back to both. The central station receives this signal from both satellites and determines the user's two-dimensional position. It is then compared to a 3D map of the surface and sent to the user via the same satellites. Since this method of operation requires two-way communication with geostationary satellites, the user terminal must have a powerful antenna. Therefore, the terminals are much larger and more expensive than those used in a GPS system.

The second system, Beidou-2, is usually called simply Beidou or Compass. It will consist of 35 satellites, 5 of which will be in geostationary orbit. The remaining satellites, as usual, will be in medium-altitude orbit. Note that this choice of altitude for navigation satellites allows the use of global navigation systems to determine the orbital position of satellites located in low orbits. Like other positioning systems, Beidou will provide two separate services, for civilian use and for military use.

In addition to the fact that a new global positioning system will simply appear, we can expect a qualitative improvement in the positioning service provided. Due to the fact that the number of all satellites will exceed three quarters of a hundred, the speed of signal reception and the operation of receivers in cities, including indoors, will significantly improve. As you know, at present it is almost impossible to catch a signal from a satellite of any global positioning system indoors or near tall buildings. Owners of communicators and smartphones with a positioning module will especially benefit from such changes, since its power often does not allow them to be used in the described conditions. Using several navigation systems simultaneously to improve the quality of the service provided can be especially simple and effective due to the fact that the data transmission frequencies of the Beidou and Galileo systems overlap significantly. It is interesting that this data became known back in 2007 after the launch of the first Compass-M1 satellite, although it was not officially announced at what frequencies this satellite operates, launched for the purpose of testing certain systems, and primarily the data transmission system. However, within about two months, specialists from CNES (National Center for Space Research, France) fully determined all the characteristics of the communication used. Let us recall that initially the PRC did not plan to deploy its own global positioning system. In September 2003, China expressed its desire to participate in the development and deployment of the Galileo system, and about a year later officially joined the development. However, at the beginning of 2008, the PRC announced dissatisfaction with the cooperation and decided to develop its own system. This may explain the similar data transmission systems used in the Beidou and Galileo satellites.

Description of BeiDou GNSS ground infrastructure

Tracking stations

The tracking stations are equipped with dual-frequency UR240 receivers and UA240 antennas, developed by the Chinese company UNICORE and capable of receiving GPS and Compass signals. 7 of them are located in China: Chengdu (CHDU), Harbin (HRBN), Hong Kong (HKTU), Lhasa (LASA), Shanghai (SHA1), Wuhan (CENT) and Xi'an (XIAN); and 5 more in Singapore (SIGP), Australia (PETH), UAE (DHAB), Europe (LEID) and Africa (JOHA).

Receivers

The navigator in the Chinese system is not only a receiver, but also a signal transmitter. The monitoring station sends a signal to the user via two satellites. The user's device, after receiving the signal, sends a response signal through both satellites. Based on the signal delay, the ground station calculates the user’s geographic coordinates, determines the altitude from the existing database and transmits signals to the user segment device.

Space segment

Current state of the satellite constellation

Currently, the BeiDou system provides satellite navigation services to consumers in China and neighboring regions, within a service area of ​​55°N. - 55° S and 55°E - 180° E, i.e. operates in servicing mode for regional consumers.

The development of the second generation BeiDou system began in 2004. In 2009, the creation of a third generation system began

By the end of 2011, 8 spacecraft were launched into orbit, BeiDou was put into operation as a regional system to provide consumers with BDS navigation services, including wide-area differential correction and short message transmission.

By the end of 2016, 14 more satellites had been launched (5 geostationary satellites, 5 inclined geosynchronous orbit (GOOS) satellites and 4 medium orbit satellites), completing the deployment of the BeiDou-2 constellation.

During the period from the beginning of 2017 to the 1st quarter of 2018, 4 pairs of BeiDou-3 satellites were successfully launched: 11/05/2017, 01/12/2018, 02/12/2018, 03/30/2018. The satellites are not yet used for their intended purpose purpose.

With the launch of the 17th and 18th medium-orbit satellites and the first geostationary satellite in November 2018, the basic Beidou-3 orbital constellation was deployed. Thus, at the end of 2018, the Beidou-3 orbital constellation included:

In medium orbits - 18 satellites; - in geostationary orbit – 1 satellite.

The systematic development of the BeiDou system continues with the release of technical information updates, the publication of plans for new launches, as well as the demonstration of the possibility of implementing a global short text message service.

On December 27, 2018, China announced the successful completion of the second phase of the BDS-3 system and the beginning of the provision of primary navigation services of the BeiDou system on a global scale.

On April 20, 2019, China launched the 44th BEIDOU spacecraft, which is also the first third-generation satellite Beidou-3 (BDS-3) in inclined geosynchronous Earth orbit.

After on-orbit testing, the spacecraft will work with 18 other BDS-3 spacecraft in medium circular orbit and another IGEO spacecraft.

The positioning accuracy of BEIDOU has reached 10 meters globally and 5 meters in the Asia-Pacific region after the system began providing global services late last year, Xinhua reported.

The positioning accuracy of the system for civilians is less than 10 meters, and the speed measurement accuracy is less than 0.2 meters per second. For military needs, positioning is carried out with an accuracy of 10 cm.

Satellite constellation in 2020

On September 30, 2015, the first BDS-3 satellite was launched, which marked the beginning of the creation of the 3rd generation of the BeiDou system (BDS-3), which by 2020 should provide a global area for providing users with navigation services with open and authorized access.

The full deployment of the BDS-3 phase orbital constellation is planned to be completed by the end of 2020. Currently, the constellation consists of 42 spacecraft, including 5 spacecraft in geostationary orbit, 3 spacecraft in inclined geosynchronous orbits and 27 spacecraft in medium-altitude orbits, including spacecraft in reserve.

On September 23, 2019, China successfully launched two Beidou-3 satellites. This was done using the Long March 3B launch vehicle and the Yuanzheng 1 upper stage rocket.

China's Beidou global navigation system will be fully operational by 2020. Dozens of spacecraft will operate in orbit to ensure its functioning. The PRC has already developed and deployed three generations of its navigation system satellites in space (BDS-1, BDS-2 and BDS-3). They help achieve precise positioning.

This launch was the 312th for the Long March series launch vehicle. Today there are 42 Beidou satellites in orbit, of which 34 are used for their intended purpose.

China is actively developing its national space program. Chinese specialists are developing meteorological, telecommunications and navigation satellites. They are also working on creating technology for lunar exploration. In addition, the exercise is implementing a project to study asteroids and Mars. They plan to begin studying it in 2020–2025.

Russia will explore the Moon together with China.

Types of spacecraft

Spacecraft in geostationary and geosynchronous inclined orbit:

BEIDOU SC IN MIDDLE-ALTITUDE ORBIT:

1. 2000-2003: Beidou experimental system of three satellites.
2. by 2012: Regional system to cover China and surrounding areas.
3. by 2020: Global navigation system.

Beidou-1

The first satellite, Beidou-1A, was launched on October 30, 2000. The second, Beidou-1B, was launched on December 20, 2000. The third satellite, Beidou-1C, was sent into orbit on May 25, 2003. The system was considered put into operation with the successful launch of the third satellite.

On November 2, 2006, China announced that Beidou would offer open services with 10-meter location accuracy from 2008. Beidou system frequency: 2491.75 MHz.

On February 27, 2007, a fourth satellite within Beidou-1, sometimes called Beidou-1D and sometimes called Beidou-2A, was also launched. It served as a safety net in case one of the previously launched satellites failed. It was reported that the satellite had problems with its control system, but these were subsequently corrected.

Beidou-2

In April 2007, the first satellite of the Beidou-2 constellation, named Compass-M1, was successfully launched into orbit. This satellite is a tuning satellite for Beidou-2 frequencies. The second satellite, Compass-G2, was launched on April 15, 2009. The third (“Compass-G1”) was launched into orbit by the Changzheng-3C carrier on January 17, 2010. The fourth satellite was launched on June 2, 2010. The Changzheng-3A carrier launched the fourth satellite from the Xichang satellite site on August 1, 2010.

On February 24, 2011, 6 operational satellites were deployed, 4 of them are visible in Moscow: COMPASS-G3, COMPASS-IGSO1, COMPASS-IGSO2 and COMPASS-M1.

According to some sources, at the beginning of 2011, the State Council of the People's Republic of China reviewed the system architecture and made adjustments to the spacecraft launch plan. It was decided to complete the formation of an orbital constellation to serve the regional consumer by the beginning of 2013. According to the adjusted schedule, the Compass/Beidou system constellation by the beginning of 2013 will include 14 spacecraft, including: 5 satellites in geostationary orbit (58.5°E, 80°E, 110.5° E, 140°E, 160°E); 5 satellites in inclined geosynchronous orbit (altitude 36,000 km, inclination 55°, 118° E); 4 satellites in medium-Earth orbit (altitude 21,500 km, inclination 55°).

On December 27, 2011, Beidou was launched in test mode, covering the territory of China and adjacent areas.

On December 27, 2012, the system was launched into commercial operation as a regional positioning system, with a satellite constellation of 16 satellites.

On May 8, 2014, the system underwent expert testing, during which it was found that in the Tianjin city area the accuracy was less than 1 meter thanks to the newly built ground correction station. .

Beidou-3

It is planned to deploy a global navigation system consisting of 35 spacecraft by 2020 (according to other sources - 36 spacecraft, according to third sources - 37 spacecraft), including: 5 satellites in geostationary orbit; 3 satellites in inclined geosynchronous orbit; 27 satellites in medium Earth orbit; several additional satellites may form an orbital reserve.

5 geostationary satellites ( Beidou-3G) will be located at orbital positions of 58.5°, 80°, 110.5°, 140° and 160° east longitude and will be launched as the service life of the existing second-generation devices expires. The satellites are based on the Chinese space platform DFH-3B, their launch mass will be about 4600 kg.

3 satellites ( Beidou-3I), which will be located in a geosynchronous orbit with an inclination of 55°, are based on the same platform, with lower power and lighter weight - about 4200 kg.

27 satellites ( Beidou-3M) for placement in medium-Earth orbit (altitude about 21,500 km, inclination 55°) are made on the basis of a new, more compact space platform using some parts of the proven DFH-3B platform. The dimensions of the satellite when folded will be 2.25 × 1 × 1.22 m, the launch mass will be 1014 kg. After completing the launch of all satellites into space, they will be placed on 3 orbital planes with 9 devices in each. Can be launched into orbit individually using the Changzheng-3C launch vehicle and upper stage YZ-1; 2 satellites each using the Changzheng-3B launch vehicle and the YZ-1 upper stage; as well as 4 satellites at a time using the future Changzheng-5 launch vehicle and YZ-2 upper stage.

In 2015, the first satellites of a new generation were launched: 2 into medium Earth orbit (BDS M1-S and BDS M2-S) and 2 into inclined geosynchronous orbit (BDS I1-S and BDS I2-S).

BEIDOU– Northern Dipper is the Chinese name for the constellation Ursa Major) Chinese national satellite navigation system.

The BEIDOU system will provide two types of global and two types of regional services. Global services are services with open and authorized access. Regional services are wide area differential correction service and short message service.

Beidou satellite constellation

The Beidou-3M/G/I satellites represent the orbital segment of the third stage of deployment of China's Beidou navigation system, using medium-Earth orbit and inclined geosynchronous orbit satellites.

Global availability of this system is planned by 2020, when all satellites will be launched. The program is managed by the China Satellite Navigation Control Center.

The concept of a system using two geostationary spacecraft (working name of the Twinsat system) was experimentally tested in 1989. The experiment was carried out on the basis of two DFH-2/2A communications spacecraft already in orbit. In 1993, Beidou was established as a program to provide China with independent access to regional and global navigation, no longer relying on foreign systems such as the American GPS and Russian Glonass system.

The first generation of experimental Beidou satellites, launched in 2000 (Beidou-1A and 1B) and 2003 (Beidou 1C), were based on the DFH-3 geostationary communications platform. In 2004, the Beidou regional navigation system began operating with an accuracy of up to 20 meters.

Another satellite, Beidou-1, was launched into geostationary orbit in 2007 to ensure that the gap between the experimental and operational Beidou systems was bridged.

During the upgrade from experimental to operational Beidou system, China plans to launch a total of 35 satellites - 5 in geostationary orbit, 27 in medium orbit and 3 in inclined geosynchronous orbits.

CAST has developed three different satellites:

1. Beidou-3M for medium orbit (27 satellites),
2. Beidou-3I in inclined geosynchronous orbits (3 satellites),
3. Beidou-3G Satellites - geostationary orbits (5 satellites).

Beidou will provide two types of services:

• a free service that is open to everyone with a compatible terminal;
• limited service for military and other applications.

Free service will provide 10 meter position accuracy, 0.2 m/s velocity measurement and 10 nanosecond timing accuracy.

The limited service will have a tracking accuracy of 10 centimeters and will include signaled data to provide system status information to users.

Beidou-2

In 2010 and 2011, five Beidou-2I satellites were launched on powerful Long March 3A rockets to insert satellites into inclined geosynchronous orbits (55°) covering China and surrounding areas. By the end of 2011, the Beidou-2 system entered service for operators in China and surrounding areas with an initial accuracy of 25 meters, which was expected to improve as more satellites were launched.

Geostationary Beidou-3G satellites are based on the DFH-3B satellite platform provided by the China Academy of Space Technology (CAST), taking components from the flight-proven DFH-3 platform and expanding its capabilities with more advanced payloads and reducing the overall weight of the platform.

The DFH-3B platform has a hexagonal shape measuring 2.2 by 2.0 by 3.1 meters with a mass of 3800+ kilograms. The Beidou satellites have a planned mass of about 4,600 kilograms with two three-segment solar panels that generate 6,800 watts of electricity. The satellite uses advanced navigation systems, including star and earth sensors, and attitude actuators, providing excellent stabilization on all three axes.

The accuracy of the station in geostationary orbit is +/- 0.05 degrees.

Beidou RNSS operates like the European Galileo and the American GPS, also using similar frequency bands. Rubidium atomic clocks provide the precise timing solutions needed to calculate the time delay from the time a signal is sent to its arrival at the receiver, which in turn allows the distance to the satellite to be calculated. In order for the receiver to calculate an accurate position, three simultaneous distance measurements to three different satellites are required.

The Beidou-2 spacecraft currently in operation transmit B1 and B2 signals, enabling open, free services in the Asia-Pacific region. It is assumed that navigation radio signals will be emitted in three frequency bands B1, B2 and B3, located in the same areas of the L-band as signals from other GNSS.

After the launch of a new generation spacecraft in 2015, the management of the Beidou program announced a change in the structure of the B1 navigation signal:

1. shift of the center frequency from 1561.098 MHz to 1575.42 MHz (like civil GPS L1 and Galileo E1 signals) and
2. changing the QPSK modulation to MBOC (similar to the modulation of the future GPS L1C and Galileo E1 signal).

This is aimed at ensuring the complementarity of the Beidou system with GNSS GALILEO and GPS.

Beidou uses eight different signals in four bands ranging from 1100 to 1600 MHz:

• B1 (carrier frequency: 1561.098 MHz / bandwidth: 4.092 MHz / modulation: QPSK),
• B1-2 (1589.742 / 4.092 / QPSK),
• B2 (1207.140/24/QPSK),
• B3 (1268.520/24/QPSK),
• B1-BOC (1575.42 / 16.368 / MBOC),
• B2-BOC (1207.140 / 30.69 / BOC 10.5),
• B3-BOC (1268.520 / 35.805 / BOC 15, 2.5),
• L5 (1176.450 / 24 / QPSK).

Beidou Ground Control Complex

It is built according to a classic centralized scheme: a network of request-free measuring stations generates readings of primary measurements of navigation parameters of radio signals from navigation spacecraft and transmits them to the system control center, which generates information placed on board the spacecraft through special earth stations.

The Beidou network of request-free measuring stations is also located in China. The long-term development strategy for the system involves the creation of a global network of stations to improve the accuracy of the Beidou system's navigation services.

Beidou navigation services became available in the Asia-Pacific region starting in December 2012.

Beidou land terminals were used after the 2008 Sichuan earthquake and became standard equipment for Chinese border guards. To measure plane coordinates, at least two satellites are required (accuracy increases with the third and fourth), which are in contact with the user terminal and a central ground station.

The user terminal receives a signal from one satellite and transmits a signal that is received by both satellites, which relay it to a ground station where the user's 2D position is calculated through the time delay of the two signals, which can be processed into 3D information using a topographic map in an algorithm that gives the user's position, which is then transmitted back via an encrypted satellite link. 150 users can be served simultaneously with this type of position search.

Priorities 2014: serve society, benefit humanity - the system is developing!

Chengchi RenRan),

general manager Chinese

Satellite Navigation Bureau

TranslationarticlesDirections 2014: Serve the World, Benefit Mankind - A System Matures (GPS World, 1 December 2013) completedJSC « PRIN» V 2013 year.

Adhering to the principles of independence, openness, interoperability, and gradual development, China is progressively deploying its own BeiDou global navigation satellite system (BDS), following the planned three-stage development strategy.

By 2000, the BeiDou demonstration satellite navigation system of the first phase of development was created. By December 2012, the regional navigation satellite system had been deployed, with five geostationary geostationary orbit (GEO), five inclined geosynchronous orbit (IGSO) satellites, and four medium earth orbit (MEO) satellites launched to form an operational constellation, and the provision of navigation services to Asia-Pacific officially began. Pacific region.

Chengchi RenRan is the Director General of the China Satellite Navigation Bureau and the Spokesperson of the Bei Navigation Satellite System.Dou. He graduated from Tsinghua University with a master's degree in industrial engineering and was previously director of the General Department of Technology at the China Satellite Navigation Project Center.

The contribution of BDS to users in China and around the world is widely recognized. The system will be fully functional and provide services to users around the world presumably by 2020.

Deploymentsystems

Taking this further, new satellites will be launched in 2014 to complement the existing constellation, while regional operational capabilities will be upgraded and expanded to international levels. In total, about 40 satellites should be launched by 2020.

Currentsystem performance

Determination accuracies from single-frequency observations in plan, height, and space were achieved at levels of less than 10 meters, 10 meters, and 14 meters, respectively. Time synchronization accuracy is less than 50 nanoseconds. The speed determination accuracy is less than 0.2 meters per second. The accuracy of the differential carrier phase solution is about 2-3 centimeters. Over the past year, the BDS system has been continuously improved and expanded, and its performance in some regions has significantly exceeded previous indicators.

Assistance in application

The use of BDS plays an important role in China, especially in the field of science and technology promotion. Chinese scientists and engineers have consciously and enthusiastically embraced the emergence of an independent navigation satellite system, and have made great strides in the research and development of navigation satellite technology, as well as new achievements in the production of navigation chips, antennas, terminals and integrated services.

In 2012, the total output of China's satellite navigation and location services industry reached 81 billion yuan (equivalent to $13.2 billion), accounting for 8 percent of the industry worldwide. At the end of 2012, the number of BDS devices for civilian use was 230,000 units, and the total output value of the BDS-related industry was close to 4 billion yuan ($652 million), accounting for about 5 percent of the total national product.

China's policy to expand the use of satellite navigation is under development. The mid- and long-term development plans for the national satellite navigation industry were issued. Satellite navigation has become one of the emerging industries of strategic importance. BDS is moving China's satellite navigation and location-related industry into a new era.

Distributionvisiblein orbitsatellitesBeiDou.

International cooperation

China upholds and adheres to the concept of "BeiDou for China and for the world", advocating the compatibility and complementarity of all navigation satellite systems, and strives to promote the global application of navigation satellite systems. To provide users with more reliable and reliable satellite navigation services, BDS has joined the international GNSS monitoring and quality assessment community. Using tracking stations around the world, international exchange of observations, and collaborative assessment studies, BDS strives to offer reliable monitoring, assessment and data to users.

To more quickly achieve the intended BDS coverage area, campaigns have been initiated to implement, demonstrate and test the BeiDou system. "BeiDou Asia Pacific Tour" and "BeiDou ASEAN Tour" were launched to accelerate the application of satellite navigation systems in many countries. To popularize satellite navigation technology, particularly to increase its acceptance and application in developing countries, BDS provided academic education, short-term training and topical lectures with the support of the International GNSS Center for Exchange and Training.

China also holds an annual satellite navigation conference, actively participates in international exchange events in the field of satellite navigation, and promotes scientific exchange, high-level forums and knowledge popularization.

Looking to the future

BDS is actively interested in:

• establishing navigation satellite differential correction systems in the Asia-Pacific region and around the world, developing more efficient services to provide real-time decimeter-level accuracy and post-processing centimeter-level accuracy;
• creation of certification and testing centers for the quality of satellite navigation products;
• accelerating the development of rules and intellectual property rights;
• joining international organizations such as the International Civil Aviation Organization (ICAO), the International Maritime Organization (IMO), the consortium developing specifications for mobile telephony (3GPP);
• strengthening compatibility and interoperability with other navigation satellite systems;
• promoting the application of BDS/GNSS in transportation, energy, government, finance, telecommunications, disaster risk reduction, relief, etc., to realize the goals of BDS to serve peace and humanity.

BDS will take full advantage of the unique advantages of navigation, communications, and differential correction services to enhance its own Short Message Service (SMS), as well as provide operational positioning and timing capabilities. BDS effectively integrates satellite and terrestrial differential correction systems and insists on introducing compatibility and complementarity between different GNSS. This will ensure its seamless integration with mobile communications, positioning services, the Internet, high quality, reliable and efficient operation for environmental and social development, public safety, and individual users.

Modern Trimble GNSS receivers support the reception of BeiDou system satellite signals with the ability to post-process the received data and operate in RTK mode: , - as standard, R8s, R9s, and - optional. All PrinCe receivers support Beidou system satellites by default.

25 /01
2019

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