From "to catch up" to "to run", from "controlled by others" to "autonomous and controllable"
China's Beidou Breakout Road
Finally, the Chinese ushered in this moment of glory, a global satellite navigation system independently developed by our country, Beidou, which completed the deployment of the global satellite navigation system constellation on June 23.
On the same day, my country's 55th Beidou Navigation Satellite, the last global networking satellite of the Beidou-3, ran from the Xichang Satellite Launch Center to Tianjiang and settled in the "big game" of the Beidou global networking. At this point, all 30 Beidou satellites are in place.
From the establishment of the Beidou-1 system project in 1994 to the completion of the Beidou-3 satellite launch mission, the Chinese Beidou people have achieved the development and launch of 55 satellites in more than 20 years. In the meantime, the Chinese Beidou people have gone through the arduous journey from "together to catch up" to "leading the leader", from "subject to control" to "independent and controllable", from "regional service" to "global guidance".
"Beidou soul asks four times"
"How to build a high-precision space lighthouse?" "Who will measure our own position?" "How does China Beidou maintain stability?" "How can many satellites of China Beidou work safely and reliably?"
In an interview with reporters, Xie Jun, deputy chief designer of the Beidou-3 project of the China Aerospace Science and Technology Corporation and chief chief designer of the Beidou-3 satellite, said that he himself was often asked such questions, and some Beidou people also asked him Call it "the four questions of the Beidou soul".
Xie Jun told reporters that the "Four Questions" involves four aspects: satellite body structure, overall navigation technology, core stand-alone development, and independent innovation breakthrough. The road to localization is difficult, and through the exploration and practice of the three-generation Beidou system, China Aerospace In the end, the person gave up a shiny answer sheet.
"We have also experienced the frustration of key single machines and components being "stuck neck" in some countries, but we have never been determined to shake the path of independent control." Xie Jun said that Beidou people know that Beidou is a national weapon and it is related to national defense. Modernization and national economic development.
"The key core technology is whether it is coming, not being able to buy it, not being able to get it." To a certain extent, this sentence is an important reason for my country's independent development of the Beidou satellite navigation system.
Chen Zhonggui, chief designer of Beidou-3 satellite, told reporters that Beidou navigation system is oriented to national security, socio-economic development, and people's life, and provides time and space location benchmarks. It has a great impact on the country and people's lives.
"If the key core technology is provided by others, where does the sense of security come from?" Chen Zhonggui said, for example, the current hot new infrastructure will be an important direction for the next stage of China's construction and development. Time benchmarks and spatial location benchmarks are crucial foundations. "The Beidou navigation system is the infrastructure of the new infrastructure, the foundation of the foundation."
As the ending star of Beidou Global Navigation System, the Beidou-3 satellite launched this time, adhering to the idea of Beidou Development has always been firmly on the road to localization, and is also a masterpiece in localization.
According to Chen Zhonggui, at the end of 2000, China built the Beidou-1 system, which solved the most basic problems of satellites, such as solar panels for power supply and distribution, which provide satellites with components that turn light into electricity, as well as the rotating mechanism of the control system. "The localization of these core products gives Beidou Satellite a "Chinese physique"."
At the end of 2012, my country completed the Beidou No. 2 system. Xie Jun said that Beidou No. 2 broke the foreign technical blockade and overcame many key technologies represented by the overall technology of navigation satellites and high-precision satellite-borne atomic clocks, which made the satellite navigation system “heart” beat out of “Chinese heart rate”.
Beidou No. 3 is the leader, starting the journey from running to leading. Xie Jun said that the Chinese Beidou people took the lead in proposing the world’s first new high-school orbit inter-satellite link hybrid system, forming a system plan with independent intellectual property rights for inter-satellite link network protocols, autonomous orbit determination, time synchronization, etc. Domestic blank.
"It is even more worth mentioning that we have established an integrated system for the localization of device components from development, verification to application, completely breaking the long-term dependence of core components on imports and being subject to people!" Xie Jun said that at this point, Beidou navigation system casting "Chinese soul".
Beidou's "Three Steps" Road
In fact, as long as the Beidou project was born, my country had worked hard in the field of satellite navigation and carried out related work in theoretical exploration and research and development. According to Chen Zhonggui, as a pioneer, the "Beacon Project", which was established in the late 1960s, was eventually terminated due to technological transformation and limited financial resources, but it was like a bright light in the night, accumulating for the latecomers. Valuable engineering experience.
At that time, the Chinese Beidou people experienced a difficult choice.
In 1983, experts and scholars represented by Academician Chen Fangyun proposed an idea to use two geostationary orbit satellites to determine ground and air targets. Later, through a large number of theoretical and technical research work, this was called the "double star positioning system" The concept of "gradually became clearer.
"The next Beidou Road, one step to the global network, or to go in stages?" Chen Zhonggui said, this issue caused a lot of controversy at the time.
In the end, the idea of "first regional, then global" was determined, and the "three-step" Beidou route was laid out.
However, in the 1990s, some countries adopted a technical blockade against my country, and domestic component manufacturers were not yet mature. The development of Beidou No. 1 could only be started in the trial and error. According to Fan Benyao, an academician of the Chinese Academy of Engineering and the chief designer of Beidou No. 1 of the fifth academy of China Aerospace Science and Technology Group, the localization started from the solar windsurfing of Beidou No. 1. At that time, many satellites did not dare to go. "Yes, I had to bite the bullet.
Afterwards, the localization of research was even more difficult. Whether it was the emergence of the Dongfanghong No. 3 platform or the key components that affected the long life span, it became a problem facing the Chinese Beidou people.
Yang Changfeng, chief designer of China Beidou Satellite Navigation System Engineering, took the atomic clock as an example. This is the core component of Beidou II. In the initial stage of development, the relevant personnel planned to import from abroad, but due to foreign reasons, they failed to achieve cooperation. The foreign technical blockade became the biggest bottleneck restricting the construction of the Beidou satellite navigation system.
"There is no core thing, our system, our entire development project will be hindered. We Beidou people firmly believe that we must come up with our own atomic clock." Yang Changfeng said.
Later, it took the Chinese Beidou team only two years to overcome the biggest technical bottleneck of the atomic clock. What is even more amazing is that the accuracy index of the spaceborne atomic clock is generally one second in 100,000 years, but now, the accuracy of the spaceborne atomic clock in the Beidou system has been increased to one second every 3 million years.
"Later, we have more independent intellectual property rights and core technologies. The localization rate of Beidou navigation satellites and key components has reached 100%. The controllable core technology is the key to the innovation and development of China's space industry. People are the most sincere gift." Chen Zhonggui said.
The legend of Chinese Beidou, to be continued
Talking about the 8 years of development of Beidou No. 2 passion burning, many Beidou people still have a fresh memory.
In 2007, it was a crucial moment for the development of the first Beidou-2 satellite. According to ITU's rules, frequency resources are time-limited and expired.
Yang Changfeng remembered that the satellite had already entered the launch tower with the rocket and was waiting for launch. Some technicians found that the satellite's transponder was abnormal. In order to prevent the satellite from having problems, the development team reopened the fairing.
"Time doesn't wait for anyone!" Xie Jun remembered that the satellite team was competing to complete all the preliminary research at the time. In order to save time, all the test participants entered the launch site and worked hard for 3 days, moving equipment, carrying cabinets, and laying cables. .
There was no respite for a moment, followed by a 200-hour uninterrupted power-up test. This time, academicians, model managers and technicians work together to rule out the danger.
Finally, at 4:11 a.m. on April 14, 2007, the rocket was successfully launched and the satellite accurately entered its intended orbit. Two days later, Beijing obtained a clear signal from the flight test star, at which time there were less than 4 hours left until the spatial frequency failed.
"After receiving this signal, we jumped with joy and excitement, and everyone's tears came out." Yang Changfeng said that through the efforts of the entire team, China's orbital frequency resources have been preserved.
In 2012, my country successfully built the world's first hybrid constellation regional satellite navigation system. At this point, my country's Beidou navigation "three-step" strategy successfully completed the first two big steps, and the foot was steady.
Just before Beidou-2 officially provided regional navigation and positioning services, the demonstration and verification of Beidou-3 global navigation system kicked off, and the development requirements were clarified, and the development goals of building independence, openness, compatibility, advanced technology, stability and reliability were determined. Since then, a new journey has begun.
"Beidou is an open system. China's Beidou and the world's Beidou. China's development of satellite navigation technology is an important infrastructure for the national economy. It is also an infrastructure that provides time and space coordinates for all mankind. Service continuity and stability Very important." Chi Jun, the chief commander of the Beidou-3 satellite of China Aerospace Science and Technology Corporation, told reporters that just as water and power cuts affect urban life, once the satellite navigation service is interrupted, the normal operation of the country and society will be greatly affected. Therefore, scientific and technological personnel have put forward strict design requirements for the reliability and continuity of satellite navigation.
According to him, in order to improve the reliability of satellite on-orbit service, Beidou-3 satellite has adopted a number of reliability measures to make the design life of the satellite reach 12 years-the advanced level of international navigation satellites, continuous service for Beidou system , Stability provides a basic guarantee.
Beginning in December 2009, the Chinese Beidou people accelerated their sprint and successfully achieved a one-year 19-star launch in 2018, once again refreshing the "Chinese speed" in space. Today, the deployment of the Beidou-3 global system constellation is fully completed, and the "three-step" strategic path has changed from "dream to hope" to "dream to hold".
Yang Changfeng revealed that in the next step, my country plans to build a national comprehensive positioning, navigation and timing system with the Beidou system as the core, more ubiquitous, more integrated and more intelligent by 2035. The legend of the Chinese Beidou is unfinished.
China Youth Daily · China Youth Daily reporter Qiu Chenhui Source: China Youth Daily
08 June 2020 Edition