BeiDou Navigation Satellite System is operating continuously and stably

TIAN Miao International Cooperation Center, China Satellite Navigation Office

Would you like to update our readers with the status of BeiDou?

In the aspect of system development, BeiDou Navigation Satellite System (hereinafter referred to as “BDS”) has successfully accomplished the second step of the mission under the “threestep” development strategy, and already formally possessed Full Operational Capability (FOC) for the Asia-Pacific region. At present, the system is operating continuously and stably, while the performance values are steady and rising. Meanwhile, the third step of the BDS development is well under way. BeiDou satellites with better performance will be launched this year. It is planned to completely establish the BDS with global coverage by about 2020.

In the aspect of application promotion, The BDS-related industries have made remarkable progresses, and already formed a complete application industry chain, which consists of fundamental products, user terminals, system applications and operating services. All-round breakthroughs have been made in some key technical areas, such as BDS core chips and modules. The related products have been used in transportation, marine fisheries, hydrological monitoring, geodetic surveying, disaster relief and reduction, mass market, and many other fields.

In the aspect of international cooperation, BDS has been continuously implementing compatibility and interoperability coordination with GPS, GLONASS, GALILEO, and other systems, accelerated to push forward BDS to join international organizations, such as the International Civil Aviation Organization (ICAO), International Maritime Organization (IMO), and Third-Generation mobile communication standard Partnership Project (3GPP). At the same time, we have established cooperation mechanism with some countries in the Asia-Pacific region, through jointly organizing “BeiDou Asia-Pacific Tour”, and carrying out extensive cooperation in sectors of precision agriculture, disaster prevention and reduction, etc.

Which are the coverage areas benefitted by BeiDou?

Since BDS possessed FOC, it mainly provides positioning, navigation and timing services for the Asia-Pacific region, and the coverage area is from 55 degree south latitude to 55 degree north latitude, 55 degree to 180 degree east longitude.

BDS has brought more navigation satellites resources to the Asia-Pacific region, where the positioning accuracy can reach 10 meters; while in some areas, especially those with low geographic latitude, the positioning accuracy is much better and can reach 5 meters.

Owing to the unique hybrid, asymmetric constellation, which consists of GEO, IGSO and MEO satellites, BDS enjoys outstanding advantages and anti-shielding capabilities based on the large number of satellites positioned in high elevation orbits. Users can enjoy more qualified services, particularly in the city canyon, multi-level interchange, and trees-sheltered environment.

With the launch of additional satellites for global constellation deployment, BDS expects to witness the gradual expansion of coverage area and increasingly enhancement of service performance. Ultimately, worldwide users will be able to enjoy free-ofcharge open services provided by BDS.

What are your plans to ensure interoperability?

What are the issues related to interoperability? BDS always upholds the principles of “openness, cooperation, resources sharing”, adheres to the concept of “BeiDou is of China, and also of the world”, and extensively participates in international exchange and cooperation, so as to realize the compatibility and interoperability among GNSS.

In the upcoming 5th session of China Satellite Navigation Conference (CSNC’2014), an interoperability workshop will be hosted by the Working Group-A under the framework of the International Committee on GNSS, on May 23rd, in Nanjing, Jiangsu Province. We plan to inquire related users and industries about the demands on interoperability, so as to provide reference for interoperability design among GNSS. During this workshop, international famous experts will discuss following technical matters in the field of interoperability, mainly including interoperable signals, GNSS differential system interoperability, time system interoperability, etc.

BDS is the advocator and facilitator of interoperability. In future, we plan to keep carrying out compatibility and interoperability coordination with GPS, GLONASS, GALILEO, and other systems, comply with international standards, and strengthen cooperation in sectors of system performance monitoring and assessment, system performance standards, so as to jointly provide better services for the world.

What is the progress in developing user standards?

In order to enable users to gain a better understanding about BDS and to make BDS serve the users better, China Satellite Navigation Office released the “BDS Signal-In- Space Interface Control Document (version 1.0)” on Dec 27th, 2012, as well as the “BDS Open Service Performance Standard (version 1.0)” and the “BDS Signal-In-Space Interface Control Document (version 2.0)” on Dec 27th, 2013. Both Chinese and English versions of above document are available on the official BeiDou website (http://www.beidou.gov.cn).

Among which, the “BDS Open Service Performance Standard (version 1.0)” provides detailed descriptions for BDS overall structure, SIS characteristics and performance specifications, system performance characteristics and specifications, etc. The “BDS Signal-In-Space Interface Control Document (version 2.0)” defines the specification related to open service signal B1I and B2I between the space segment and the user segment of BDS, identifies the coordinate system and time system adopted by BDS, specifies B1I and B2I signal structure, basic signal characteristics and ranging code, and provides NAV message. With the publication of the ICD (version 2.0), BDS has become the first system which possesses two civil navigation signal frequencies with full service capability, while relevant enterprises can develop dual-frequency, high-precision BDS receivers, to enable the users enjoy navigation services with higher accuracy.

What are your plans in developing BeiDou market?

With the aim of developing BDS market, firstly, we will make our commitment with responsibility that BDS will provide open services free-of-charge, currently for the Asia-Pacific region and eventually worldwide; secondly, we will continue to implement BDS/GNSS application demonstration and experience campaign, through promoting enterprises exchanges, organizing technical symposiums, constructing demonstration programs, to enable international users gain a better insight into BDS and practically enjoys the benefits of BDS; thirdly, we will improve and enrich the development plan of BDS and related industries, enhance policy guarantee to push forward the exploration of market and boosting of application industries; fourthly, we will keep upgrading core technologies, speed up constructing BDS ground-based augmentation system and China Location- Based Network, to lay a foundation for industrial ecosystem of BDS.

Could you highlight the challenges before BeiDou?

So far, BDS has completed the 2nd step of development plan smoothly. In the near future, it will focus on ensuring continuous and stable operation, offering stable and reliable PVT services for users; facilitating industrial applications and development; promoting the joint development of GNSS, to enable resource-sharing and mutual complementarity among GNSS.

Since the GNSS industry has entered into a multi-sytem integration era instead of a single system, satellite navigation is developing towards better performance, more reliability and higher efficiency. During such a process, BDS is faced up with the long-term challenges to provide stable and reliable PVT services for users, make not only neighboring users but also global users benefit from the development of BDS, and accomplish the objective of “serve the world and benefit the mankind” at the earliest stage. All above are the challenges we are confronted with.