Develop all payloads for the Beidou-1 and Beidou-2 satellites, and provide all payload ...... for 20 of the 30 Beidou-3 satellites for the global networkIn the past 30 years, the Xi'an Branch of the Fifth Academy of Aerospace Science and Technology Group (hereinafter referred to as the Xi'an Branch), located in the space base, has been the core unit of the overall design of China's Beidou navigation satellite payload and the development of system products, and has promoted China's Beidou satellite navigation system to achieve three leaps from scratch, from active to passive, and from regional to global.
Beidou-1 opens a new chapter
In January 1994, the Beidou-1 project was officially established, and China began to build an independent Beidou satellite navigation system.
The Xi'an Branch undertook the technical research and product development of the satellite payload system and tracking subsystem, including the development of the first-class device subsystem, antenna subsystem and tracking subsystem.
From the successful launch of the first Beidou navigation test satellite to the fourth Beidou navigation test satellite going to space, in the development process of the four satellites, the research team of Xi'an Branch has accumulated a lot of reserves for the follow-up mission in terms of technology and system integration, laying the foundation for the implementation of the Beidou-2 satellite and the follow-up mission.
Multi-technology breakthroughs help Beidou take another step
The successful operation of the Beidou-1 satellite navigation system has made China the third country in the world to have an autonomous navigation and positioning system. At the same time, the strategic goal of the Beidou Navigation Satellite System to achieve regional networking and provide global navigation and positioning functions needs to be realized urgently.
In September 2004, the Beidou-2 satellite navigation system was officially approved. The Xi'an Branch undertook the research and development of all the satellite navigation subsystems and antenna subsystems of Beidou-2. Not long ago, breakthroughs were made in the development of satellite payloads, such as spaceborne rubidium clocks, precision spread-spectrum ranging, and navigation information processing.
At that time, as a new generation of navigation system in China, navigation engineering was generally faced with problems such as difficulty in achieving high-precision indicators and improving anti-interference capabilities. In this regard, the technology of satellite payload system is facing a number of breakthroughs in key technologies represented by high-stability spaceborne atomic clock technology, spaceborne precision ranging technology, and continuous and stable navigation signal generation technology.
Among them, the rubidium atomic clock is known as the "heart" of navigation satellites in the industry, and the time benchmark it provides will directly affect the function and performance of navigation satellites. After joint research and fierce competition by a number of units, the research and development team of Xi'an Branch successfully delivered more than 30 positive spaceborne rubidium clocks to achieve perfect performance in orbit.
At 4:11 a.m. on April 14, 2007, China successfully launched a Beidou navigation satellite into space with the "Long March-3A" carrier rocket at the Xichang Satellite Launch Center. Photo by Xinhua News Agency reporter Li Gang.
In April 2007, the first Beidou navigation satellite was launched into orbit, which not only completed the in-orbit verification of payload technologies such as domestic rubidium clock and navigation signal design, but also completed the important tasks of seizing frequency resources, exploring the orbital electromagnetic environment and establishing a positive state.
In October 2012, the construction of China's Beidou-2 satellite navigation constellation was successfully completed, and it began to provide satellite navigation services to the Asia-Pacific region.
The "Beidou Network" covers the whole world.
The space segment of the Beidou-3 Global Navigation Satellite System consists of 30 networked satellites, and the Xi'an Branch undertook the development of all the payloads of 20 satellites and incremental payloads such as global short message communication and search and rescue.
In March 2020, the 54th Beidou navigation satellite was successfully launched, and the Xi'an Branch provided payload products such as navigation subsystem, antenna subsystem, and first-class device subsystem for the satellite, helping the Beidou-3 global satellite navigation system networking usher in the "race point".
In the same year, the Beidou-3 global navigation satellite system was officially launched. It can not only provide high-precision, high-reliability positioning, navigation and timing services for all kinds of users around the world around the clock, all day, but also has a unique short message communication function.
After the completion of the Beidou-3 global satellite navigation system, the spaceborne rubidium atomic clock developed by the Xi'an Branch has achieved an accuracy of one second in 3 million years, and the navigation service capability is at the world's advanced level. In 2023, three Beidou-3 network replenishment satellites will be launched one after another, and the Xi'an Branch will participate in the development of all payloads.
Sun Jiadong, the first chief designer of China's Beidou satellite navigation system project, once praised the research and development team of Xi'an Branch as "promising". After 30 years, both Xi'an Branch and China Beidou have changed from "promising" to "promising".