Directions 2019: BeiDou accelerates global deployment

Yang Changfeng, chief architect of China’s BeiDou navigation satellite system. (Photo: BeiDou)

By Yang Changfeng
Chief Architect, BeiDou Navigation Satellite System

As one of the core GNSS, the BeiDou Navigation Satellite System (BDS) has been developed following a three-step development strategy. By around 2020, BDS will form a space constellation consisting of 30 satellites, including three satellites in geostationary earth orbit (GEO), three satellites in inclined geosynchronous satellite orbits (IGSO), and 24 satellites in medium earth orbits (MEO). It will provide free open and high-quality services, including navigation, positioning, timing, short message communication, search and rescue, and so on to the users worldwide.

In 2018, BDS has made fruitful results in the aspects of system construction, integrated applications, and international development.

System Construction

The stable operation of the BDS-2 constellation and construction of the BDS-3 constellation have resulted in solid achievements, while the deployment of the ground-based and satellite-based augmentation systems has made remarkable progress, and the International Multi-GNSS Monitoring and Assessment System (iGMAS) has been in stable and continuous operation

BDS-2 Improved Regional Services. Through upgrades and enhancements of the ground system, the service performance, stability and availability of the BDS-2 constellation has been improved. The analysis results shows that the nominal positioning accuracy of BDS-2 in its coverage area is better than 5 meters. To achieve user-oriented services, the Interface Control Document (ICD) for the open service signal B3I has been released.

The basic system of iGMAS has been completed, consisting of 24 ground stations and various centers, to provide raw data, basic products, and monitoring and assessment information services to users through the Internet and smartphones.

BDS-2 Positioning Performance. (Chart: BeiDou)

BDS-3 Constellation Deployment. By late 2018, 16 MEO BDS-3 satellites and 1 BDS-3 GEO satellite were in orbit. China successfully launched the 18th and 19th BDS satellites on Nov. 19. Deployment of the basic BDS-3 constellation has been accomplished.

The BDS-3 satellites are equipped with the higher-performance rubidium atomic clocks with stability of E-14 as well as hydrogen atomic clocks with stability of E-15. The signal-in-space (SIS) accuracy will be superior to 0.5m, the position accuracy will reach 2.5 to 5 meters, and the overall performance will be dramatically improved. The in-orbit test results have indicated that the BDS-3 satellites are in sound condition, and the performances can satisfy nominal parameters. For the convenience of public applications, the ICDs of the new signals, B1C and B2a, have been released.

BDS-3 will inherit the short message communication service from its predecessors, and will further enhance the basic PNT service capabilities. Satellite-Based Augmentation System (SBAS) and Search and Rescue (SAR) services will be developed according to the international standards.

Ground-Based Augmentation. The BDS/GNSS Ground-based Augmentation System has completed the deployment of 155 framework reference stations and nearly 2,400 regional stations in China. The system has carried out high-precision applications in many fields, such as surveying, national resources, disaster mitigation, transportation, meteorology, and offered basic services for users, including real-time navigation services at meter-level and decimeter-level, as well as precise positioning services at centimeter-level and millimeter-level.

China’s National Reference Station Network. (Image: BeiDou)

First SBAS GEO Satellite. The BeiDou Satellite-based Augmentation System (BDSBAS) is being developed in accordance with the International Civil Aviation Organization (ICAO) standards, to offer navigation services with superior accuracy and integrity.

In November 2018, the first GEO satellite with SBAS and SAR payloads has been successfully launched. The short message communication service offered by the satellite will be fully compatible with that of BDS-2, while the service volume will be increased by 10 times and the user’s transmit power will be reduced to 1/10. As the result, the user terminals will possess smaller size, higher integration and enhanced capacity.

Integrated Applications

As the system construction accelerates, BDS is also making great efforts to strengthen the development of fundamental products and applications in various fields. The integrated applications adopt the “BDS+” model, to stimulate the growth of satellite navigation industry.

Fundamental Products. At present, the fundamental BDS products have been used in mass market applications, of which the performance has reached or close-to the world-class level. By the 3rd quarter of 2018, the sales volume of BDS navigation chips and modules exceeded 70 million pieces, and the amount of the BDS-enabled terminals surpassed 500 million pieces or sets. In 2017, the domestic output value is more than RMB 250 billion (US $ 36 billion), in which the BDS contribution exceeds 80%.

Industrial Applications. BDS continues to facilitate the integrated applications and development of related industries; to bring GNSS high-precision services in combination with cloud computing, internet of things, big data and other technologies; to push forward the fusion among BDS-related industries and high-end manufacturing, software, integrated data industries, and to enable BDS-based applications to solve the problems associated with national economy and people’s livelihood. BDS has been integrated into various national significant infrastructures, by providing time and space references for transportation, meteorology, agriculture, electricity, communications, finance and other industries.

Meanwhile, “BDS+” and “Time and Space+” applications targeted towards the mass market are enjoying a broader future prospect. The BDS-based navigation services have been adopted by various enterprises in the fields of smart mobile terminal manufacture, location-based services (LBS), e-commerce, and so on. The BDS-based LBS have been widely use in the public consumption sector and people’s livelihood, which have been changing people’s life by providing more conveniences for the public.

BDS International Development. BDS continuously pushes forward international development, carries out practical cooperation and exchanges, and promotes the development of GNSS community, to better serve the world and benefit mankind.

BDS actively participates in related activities under the framework of the United Nations, other international organizations and multilateral platforms. In June, 2018, BDS took part in the UNISPACE+50 Exhibition and donated a BDS-3 satellite model to the United Nations Office for Outer Space Affairs.

In November 2018, the 13th Meeting of the International Committee on Global Navigation Satellite Systems (ICG-13) was successfully held in Xi’an, China. His Excellency Xi Jinping, President of the People’s Republic of China, sent a congratulatory letter to the ICG-13, and expressed that “China is willing to work with all countries, to share the construction and development achievements of BDS, and to jointly promote the development of global satellite navigation.” More than 400 representatives from 16 nations and 16 regional and international organizations attended the meeting and made in-depth exchanges on over 20 topics related to satellite navigation.

BDS has always been exploring joint applications with other compatible navigation satellite systems, and carrying out bilateral coordination and cooperation.

In November 2017, the Joint Statement of BDS and GPS Signal Compatibility and Interoperability was signed, which stated that the two systems were radio-frequency compatible within the framework of ITU, and BDS B1C civil signal and GPS L1C civil signal had achieved interoperability.

In November 2018, the Agreement between the Government of the People’s Republic of China and the Russian Federation on Cooperation in the Field of the Use of BDS and GLONASS for Peaceful Purposes was signed, which would facilitate the complementarity and integrated development, promote practical cooperation projects, and contribute to more efficient and reliable services for global users.

At present, BDS has covered more than 50 countries and over the population of 3 billion people. The BDS-related products have accessed to the markets of over 80 countries and regions. In April, 2018, the first overseas BDS/GNSS Center was opened by China Satellite Navigation Office and the Arab Information and Communication Technology Organization, to enrich the public awareness, experience and applications of BDS in Arab nations.

The international GNSS Monitoring and Assessment System (iGMAS) has contributed to the implementation of the Asia-Pacific Space Cooperation Organization project, iGMA-International GNSS Service Pilot experimental project, and Sino-Russian monitoring and assessment cooperation, and has provided GNSS users with authentic third-party assessment results.

Future Plans

BDS will continuously promote joint applications of multiple navigation satellite systems, and provide global users with diversified choices for better application experiences. BDS welcomes users and equipment providers worldwide to participate in the Global Users’ Experience and Evaluation Campaign (relevant information can be referred to the BDS official website), and will release the experience and evaluation results when appropriate.

By the end of 2018, BDS-3 will possess the initial operational capability and implement all-round validation on its global service performance. Between 2019 and 2020, BDS will keep improving its continuous stability and service accuracy, maintain the BDS-2 service performance stable and enhanced, and continue the BDS-3 deployment by launching another 6 MEO satellites, 3 IGSO satellites, and 2 GEO satellites, to eventually possess global service capabilities by 2020.