At 5:10 on September 23, 2019, China successfully launched the 47th and 48th Beidou navigation satellites at the Xichang Satellite Launch Center in the form of "one arrow and two stars".
At 5:10 on September 23, Beijing time, China successfully launched the 47th and 48th Beidou navigation satellites in the "One Arrow Double Star" mode with the Long March 3B carrier rocket and the supporting expedition No. 1 at the Xichang Satellite Launch Center. Guo Chaokai / Wen Zhang Wenjun / photo
Since 1994, China launched the construction of the Beidou No. 1 system project. China’s Beidou has been moving forward. In accordance with the “three-step” development strategy, it has developed an innovative development path suited to China’s national conditions.
Today, Beidou has become an important force in the global satellite navigation system. For the global network, Beidou has launched a comprehensive sprint. In the future, China Beidou will work alongside other satellite navigation systems to provide positioning, navigation and timing services with higher precision, more stable operation and more reliable functions. It will become a major public service space infrastructure for the whole world, and build a community of human destiny. "China contribution."
Grab the "Navigation Club" before "closing the door"
In the Gulf War of 1990, GPS-loaded precision strike weapons were used for the first time on a large scale, and the operational effectiveness shocked the world.
If the missile is a gun, the atomic bomb is a bullet, and satellite navigation is a precise sight. As early as the 1970s, Chinese astronauts started the “Lighthouse One” project to explore, but the project was forced to dismount due to difficulties in economic and technical support.
But the Chinese’s determination to build a satellite navigation system has not wavered. After continuous exploration, China has gradually formed a "three-step" strategy from the construction of the Beidou No. 1 test system to the Beidou-2 regional navigation system to the Beidou No. 3 global system.
In 2000, China launched two geostationary orbit Beidou satellites, which creatively achieved dual-star active positioning, and provided both time-based and short-message communication services. The program utilizes China's existing mature technology to realize the autonomous controllability of satellite navigation system construction with minimum input and minimum period.
At the start of the Beidou No. 1 project, the US GPS and Russian GLONASS have launched more than 20 navigation satellites respectively, occupying the most suitable golden band for satellite navigation. China and the European Union, which is building the Galileo system, are pushing ITU to squeeze a small segment from the aeronautical navigation band for use. On April 18, 2000, the Beidou and Galileo systems were simultaneously declared. According to the ITU rules, it is necessary to launch a navigation satellite within 7 years and successfully transmit and receive the corresponding frequency signal in order to obtain the orbital position and frequency resources, otherwise the legal status cannot be obtained.
In 2005, the European Union launched its first Galileo navigation satellite. At this time, although China has launched three Beidou test satellites, it does not have the ability to actively transmit downlink signals. The Beidou-2 satellite, which complies with ITU regulations, is still under development and time is tight.
The Beidou people have a back-to-back battle, and the development cycle has been greatly shortened. At the same time, Xichang Satellite Launch Center also overcomes many challenges such as using the newly-reformed launching station for the first time, using the remote control mode for the first time, and launching the first-round orbiting satellite for the first time, analyzing risks, formulating measures, and controlling nodes for this task. Well prepared.
At 4:11 on April 14, 2007, the Beidou satellite, carrying an important mission, took off and signaled back at 20 o'clock on April 17. at this time. There are only less than four hours left in ITU's “seven-year limit”.
The first hybrid navigation constellation
Satellite navigation systems such as GPS adopt a single orbital constellation configuration, and all networked satellites operate in a medium-circle orbit at a height of 20,000 kilometers.
However, the Beidou system cannot establish ground monitoring stations around the world like GPS. Yang Hui, chief designer of Beidou No. 2 Engineering Satellite System, said that due to the limitations of the national land station, Beidou must create a constellation that can be jurisdictiond within the national territory. For this reason, it is necessary to adopt a hybrid network of high- and medium-rail satellites. But this faces a series of worldwide problems.
Through unremitting efforts, the Beidou team solved the problems of attitude control and high-precision temperature control of high-orbit navigation satellites, and improved the accuracy, continuity and usability of system services. At the end of 2012, the Beidou-2 regional satellite navigation system consisting of 14 satellites was completed, providing positioning and navigation time service for most parts of Asia Pacific around the clock.
"Beidou No. 2 pioneered the synchronous orbiting navigation satellite in the world, and at the same time pioneered the hybrid navigation constellation with geosynchronous orbit satellites, tilted geosynchronous orbit satellites and medium-orbit satellites." The former deputy chief designer of the project, Beidou Li Zuhong, senior consultant of the system, said that for regional navigation systems, this combination can achieve the best coverage with the least number of satellites and has gained international recognition.
At the same time as the construction of Beidou No. 2 project, China launched the construction of the global system of Beidou No. 3 in 2009.
Traveling wave tube amplifiers are key components of communication satellites and have long relied on imports. In 2014, when China was conducting the development of the Beidou No. 3 test satellite, the foreign party suddenly notified that the supply was stopped due to government reasons.
However, the Beidou team has long recognized the importance of localization for the construction and stable operation of the Beidou system. At the same time as the construction of the Beidou No.3 system was launched, the Chinese Academy of Aerospace Science and Technology Group launched a technical research on the localization of key components such as wave tube amplifiers for a number of units within the United Nations.
The foreign party has learned that China's traveling wave tube amplifier technology has made breakthroughs. After the Beidou team decided to replace imported products with domestic products, it hurriedly indicated that it could supply and cut the price by half. This allowed the Beidou team to taste the sweetness of the core, and strengthened its determination to take the road of localization.
After several years of hard work, the long-term dependence on imported DC-wave amplifier components, microwave switches, high-power power controllers, momentum wheel assemblies, star sensors and other key products has achieved the main localization and backup. The localization rate of Beidou No. 3 satellite components reached 100%.
At 2:07 on November 19, 2018, China used the Long March 3B carrier rocket at the Xichang Satellite Launch Center to successfully launch the 42nd and 43th Beidou navigation satellites in a "one arrow and two stars" manner. The two satellites launched this time belong to the China Earth Orbiting Satellite and are the 18th and 19th satellites of the China Beidou III system. Liang Shuyan
China Beidou is open to the world
On February 28, 2017, China's first self-developed "meter-level rapid positioning Beidou chip" was officially launched, achieving the independent control of the basic products and reaching the international advanced level.
"The vast majority of smartphones in the world have already adopted chips that support Beidou." Director of China Satellite Navigation System Management Office, Qi Chengqi, revealed at the press conference held on December 27, 2018, that Beidou system has entered 3GPP International. Mobile communication organization.
In addition to the “Beidouxin”, China Beidou has also formed a complete industrial chain consisting of basic products, application terminals, application systems and operational services. Beidou has been standardized in key national industries and key areas, and is applied in a large-scale application in the mass consumption field.
According to statistics, the output value of the domestic satellite navigation industry has exceeded 300 billion yuan in 2018; it is estimated that by 2020, the scale of China's satellite navigation industry will exceed 400 billion yuan, and Beidou will drive more than 300 billion yuan in market share.
As of April 2019, there were more than 6.2 million operating vehicles, 30,000 postal and express vehicles in China, about 80,000 buses in 36 cities, more than 3,200 inland navigation facilities, and more than 2,900 maritime navigation facilities. More than 50,000 sets of agricultural machinery and equipment, and more than 45,000 sets of Beidou terminals...
With the integration of emerging technologies and industrial models such as Internet+, 5G, artificial intelligence and sharing economy, satellite navigation technology has also spawned new models and industries for economic development such as precision agriculture, precision logistics, autonomous driving, intelligent transportation, and smart cities. The development of new formats is being integrated into all aspects of society in an unprecedented depth and breadth.
In today's world, GPS, Beidou, GLONASS, and Galileo are four major satellite navigation systems. How do you view the relationship with other navigation systems? The Beidou system has given the answer since the beginning of construction: It has always practiced the concept of “China’s Beidou, the world’s Beidou”, which is compatible with other satellite navigation systems and develops together to benefit the “family” of the world.
Today, China Beidou has opened its mind and waits for the acceptance of the world.