China launches last piece of BeiDou Navigation Satellite system into orbit
China’s final BeiDou-3 satellite for its global navigation system was launched on June 23, 2020, at 9.43am, from the Xichang Satellite Launch Centre in the southwest province of Sichuan. A Long March 3B rocket carried the satellite into geostationary orbit, completing the third-generation network for the BeiDou Navigation Satellite System (BDS). BDS is the fourth major global satellite navigation system, following GPS built by the US, Russia’s Glosnass and the European Union’s Galileo.
Carrying the last satellite of China’s domestically developed BeiDou Navigation Satellite System, or BDS, the Long March-3B launch vehicle blasted off from the Xichang Satellite Launch Center on Tuesday morning.
And after a flight of around 30 minutes, the spacecraft, the third geostationary Earth orbit (GEO) satellite and 30th of the third-generation series of the BeiDou system, or BDS-3, successfully entered its planned orbit, marking the completion of the global geolocation network, which is also China’s largest space-based system and one of the four global navigation networks, along with the US’ GPS, Russia’s GLONASS and the European Galileo.
The launch of the final satellite of China’s indigenous BeiDou system had been previously scheduled on June 16, but was delayed after technical problems were found with the Long March-3B rocket in pre-launch tests.
Space launches have always been full of challenges and sometimes faced with high risks of failure. The postponement of the final BeiDou launch and resumption after resolving the problems once again demonstrated that Chinese space scientists uphold the scientific spirit, allowing zero errors at any stage of the mission, insiders said.
The latest GEO satellite is the 55th BDS system, and will work with other members of the network, allowing global users to access high-accuracy navigation, positioning and timing as well as communication services.
Compared to previous generation series, the constellation of BDS-3 with an array of 30 satellites flying on three different orbit planes – three at the GEO, three at the inclined geosynchronous orbits, and 24 at the medium Earth orbit, have higher bandwidth, enabling enhanced communication capability and carrying more accurate and stable atomic clocks to improve the precision of timing and navigation services, according to the project contractor China Academy of Space Technology under the state owned space giant China Aerospace Science and Technology Corporation (CASC).
The BDS-3 also possesses better messaging capability, increasing its unique short message service capacity from 120 Chinese characters to 1,200 per message, and the higher communication bandwidth also expands the user capacity from 500,000 to 5 million users.
BDS-3 is also capable of providing precise point positioning service (PPP) with a decimeter-level dynamic accuracy and centimeter-level static accuracy, meaning it can support applications such as auto-pilot for vehicles and precision docking of ships.
Yang Changfeng, the chief architect of the BDS, told the Global Times on Monday that China’s BDS is compatible with the US’ GPS, Russia’s GLONASS and Europe’s Galileo, and users worldwide can freely choose any four satellites with the best signals from the global navigation satellite systems with over 100 satellites.
According to the chief architect, the BDS has satellites on three orbit planes in the Asia-Pacific region, which makes it more capable of resisting disturbances from occlusion even in such environments with multi-layer surfaces in the urban areas as well as in forests.
Users in low latitude areas in the Asia-Pacific region can enjoy non-stop navigation services from the BDS in these circumstances, and the accuracy of the BDS service is just as good as that of the US’ GPS, and of world-class quality globally, Yang noted.
According to the China Satellite Navigation Office on Tuesday, the majority of the world have started using the BDS.