BDS: Enhancing system operations and application development, and advancing new technologies

December 21, 2023  - By
Figure 1. Global position accuracy of the BDS B1C signal (95%) Chart: Test and Assessment Research Center of China Satellite Navigation Office

Figure 1. Global position accuracy of the BDS B1C signal (95%)  Chart: Test and Assessment Research Center of China Satellite Navigation Office

Over the past year, the BeiDou Navigation Satellite System (BDS) has been continuously striving for world-class excellence throughout its development, especially in the system operation and the development of applications and new technologies. With this relentless innovation and pursuit of excellence, BDS continues to surpass its benchmarks.

System Operation and Services

The establishment of an on-orbit support system and the enhancement of on-orbit operational controls, combined with in-orbit software reengineering and real-time ground diagnostics, have significantly improved BDS’s functionality and service performance. Both space and ground segment operational statuses are regularly evaluated within the engineering framework. Various data sets and schemes are rigorously tested and reviewed to ensure the utmost level of user satisfaction.

In addition, the system integrates new techniques, such as joint satellite-to-ground and inter-satellite control, unified information transmission and coordinated processing of observation data. Combined with artificial intelligence, cloud platforms and big data analytics, the continuous global monitoring and assessment capability for BDS/GNSS has been upgraded.

In May, the first BDS-3 GEO backup satellite was successfully launched. Currently, BDS operates a total of 46 satellites in orbit, comprising 15 in the BDS-2 constellation and 31 in the BDS-3 constellation. Since its official commissioning, BDS has been consistently providing reliable services with steadily improving performance metrics. Data from the International GNSS Monitoring and Assessment System (iGMAS) in 2023 indicate that the BDS space signal availability is 100%, signal continuity is 99.996%, and the global positioning accuracy is 5 m, with notable enhancement observed specifically within the Asia-Pacific region. Figure 1 shows the positioning accuracy of the BDS B1C signal assessed with global monitoring stations. Figure 2 shows the number of visible BDS satellites, with a minimum of six to eight satellites consistently in view globally.

BDS remains committed to serving the global community and benefiting humanity by promoting innovations that seamlessly integrate the fundamental positioning, navigation, and timing functions of the system, while building four major service platforms to support the development of BDS distinctive service applications. The International Search and Rescue Service Platform provides MEO search and rescue services that comply with COSPAS-SARSAT standards and offer BDS-based characteristic return link services. The satellite-based augmentation system (SBAS) service platform provides the single-frequency augmentation service using the B1C signal in accordance with APV-I requirements as well as the dual-frequency augmentation service using the B2a signal in accordance with CAT-I requirements. The short message service platform achieves seamless integration with terrestrial mobile communication systems and the Internet, marking a breakthrough in enabling smartphones to connect directly to satellites and bringing regional short message communication services to mainstream smartphone users. The ground-based augmentation service platform has a nationwide network of ground stations and provides high-precision positioning augmentation services in real time, with accuracy levels ranging from meters, to decimeters, to centimeters and even to millimeters for post-processing, to meet the needs of various industries and the general public.

System Applications and Industrialization

Xie Jun

Xie Jun

The BDS application industry has experienced sustained growth. In 2022, China’s satellite navigation and location-based service industry reached a total output value of RMB 500.7 billion (approximately $71.5 billion USD). A complete industrial chain has been established, including chips, modules, antennas, boards, receivers and comprehensive services.

The basic BDS products have been continuously developed and have reached a production scale of hundreds of millions. In 2022, the sales of in-car navigation devices in China exceeded 12 million units. Sales of various receivers, including those for IoT, wearables, vehicles and high-precision equipment, exceeded 100 million units. Intensive research and development efforts are underway to integrate BDS navigation capability with inertial, mobile communication and visual navigation methods to enhance the user experience in various application scenarios.

BDS is extensively used in a wide range of sectors and is proving to be a key technological driver of socio-economic growth. In the transport sector, more than 7.9 million road vehicles, more than 40,000 postal and express delivery vehicles, more than 47,000 ships, more than 13,000 aids to navigation on waterways and nearly 500 general-purpose aircraft use BDS.

In agriculture, forestry, livestock and fisheries, more than 100,000 autonomous agricultural machine units, more than 20,000 intelligent livestock tracking collars and more than 100,000 fishing vessels are equipped with BDS receivers. In the water resource management area, the BDS Short Message Service supports hydrological monitoring of more than 2,500 reservoirs. In digital construction, the synergy of BDS with multi-sensor and Internet technologies has proven essential for projects such as the Chengdu-Kunming Railway, the Shenzhen Mawan Undersea Tunnel and the Xinjiang Desert Highway, significantly improving construction quality and efficiency while reducing labor and material costs.

Significant progress has been made in consumer applications. In 2022, 260 million of the newly registered smartphones in China supported BDS, accounting for 98.5% of the total. The BDS short message service has been seamlessly integrated into mainstream smartphones, eliminating the need to change SIM cards, phone numbers or add external devices. Consumers can now access BDS-3’s short message services. BDS-based lane-level navigation has been piloted in eight cities in China, with nationwide deployment planned. BDS-enabled features such as “Dynamic Traffic Light Countdown” and “Traffic Light Status” have covered millions of traffic signals in China, with daily signal queries exceeding 1.4 billion. Moreover, prominent domestic on-line mapping service providers deliver BDS satellite positioning service hits more than 300 billion times daily.

Figure 2. Number of visible BDS satellites Chart: Test and Assessment Research Center of China Satellite Navigation Office

Figure 2. Number of visible BDS satellites Chart: Test and Assessment Research Center of China Satellite Navigation Office

International Cooperation and Exchange

China has strengthened bilateral partnerships to expand cooperation initiatives. In March 2023, the China-Russia Satellite Navigation Major Strategic Cooperation Project Committee was upgraded to the China-Russia Satellite Navigation Cooperation Subcommittee, which held its inaugural meeting in October. The fourth China-Arab States BDS Cooperation Forum was successfully convened in October. Active participation in international events under multilateral organizations such as the United Nations and academic exchanges in the field of satellite navigation have promoted joint discussions on global satellite navigation, ensuring the compatibility and interoperability of navigation satellite systems worldwide.

China has promoted the integration of BDS into international standards set by sectors including civil aviation, maritime, mobile communication, as well as search and rescue. In November 2022, the BDS Short Message Service System became the third global satellite communication system for maritime distress and safety, as recognized by the International Maritime Organization (IMO). In June 2022, the technical standards for BDS B2a and B3I signals were approved by 3GPP, leading to the formal release of BDS-assisted positioning standards for fourth- and fifth-generation mobile communication systems. In November 2022, China officially became a space segment provider for COSPAS-SARSAT.

Intensive efforts have been made to create an enabling “soft environment” through policymaking, standardization and IPR protection to maintain open communication and sustainable development. With the release of “The BeiDou Satellite Navigation Standard System (version 2.0)” in 2022, China has submitted more than 7,000 patent applications related to satellite navigation, underscoring its commitment to innovation and high-quality development. In November 2022, the Information Office of the State Council of China released a white paper entitled “China’s BeiDou Navigation Satellite System in the New Era,” which captures BDS’ transformative journey: unveiling new service capabilities, driving industrial growth, promoting collaborative initiatives and charting future paths.

In April, the 13th China Satellite Navigation Conference was successfully held under the theme “Digital Economy —Intelligent Navigation.” For the first time, challenges related to satellite navigation and positioning, navigation and timing (PNT) systems were solicited and later published on the official BDS website. These challenges cover current and emerging GNSS technologies, services and applications, including the establishment and maintenance of GNSS satellite-based spatial-temporal reference services, the provision of high-precision navigation and timing services in lunar space, the provision of accurate positioning services in complex environments, and the deployment of intelligent applications. In addition, proposals were made to develop a unified theory of multi-source heterogeneous spatial-temporal information for PNT applications, aiming to further integrate BDS, PNT and other new information technologies.

Prospects of Future Development

In the future, two to four backup satellites are scheduled to be launched to strengthen the robustness and accessibility of the BDS constellation. Commitments have also been made to continuously raise the standards of intelligent BDS ground operations and maintenance to ensure stable operation and performance improvement. In addition, system management and routine assessments will be strengthened, with a comprehensive strategy for both space- and ground-based operations to optimize the operational ecosystem and enrich BDS services and user experience.

In the area of emerging technologies, research on improving navigation with low-Earth orbit technologies, as well as its practical applications, will be further promoted to strengthen the precision and integrity of the system and to meet the requirements of an era characterized by ubiquitous connectivity and intelligent devices. Efforts will also include studies on multi-layer space constellations and the fundamentals of lunar space navigation to extend the coverage of BDS services. In addition, research will continue on satellite-based autonomous timekeeping technologies and pulse star technologies, with the aim of establishing and maintaining GNSS satellite-based spatial-temporal reference systems.

With the fundamental philosophy of “independent innovation, open integration, unity of all, and pursuit of excellence” in mind, the integration of BDS with innovative realms such as 5G, artificial intelligence, and big data will be accelerated steadfastly, aiming to shape a national PNT system that’s more ubiquitous, integrated, and intelligent by 2035.

The vast cosmic arena beckons for collaborative exploration. BDS will remain anchored to its mission. BDS is developed by China, dedicated to the world and strives to be first class. With a resolute ambition to promote progress, BDS strives to make significant contributions to the development of human society and a community with a shared future for mankind.

About the Author: Xie Jun

Xie Jun is the Deputy Chief Architect, The BeiDou Navigation Satellite System.