On June 23, after the successful launch of the 55th Beidou satellite, it was tested in orbit for nearly a month. The test results were all qualified. The Beidou satellite navigation system is about to realize global networking. This indicates that the Beidou satellite navigation system will side by side with other global satellite navigation systems to provide positioning, navigation and timing services for the world. This is my country's first major global public service space infrastructure.
After 30 years of arranging stars from Beidou-1 to Beidou-3, what are the unknown stories behind the birth of Beidou navigation system?
30 years of sharpening a sword
The Beidou satellite navigation system grew out of nothing, from weak to strong!
The Beidou-1 satellite navigation system project was officially launched in 1994, and the Beidou-3 system will be completed in 2020 to provide services to the world. After nearly 30 years of hard work, China has now become the third country in the world with an autonomous satellite navigation system after the United States and Russia.
Xie Jun, the deputy chief designer of the Beidou-3 project and the chief designer of the Beidou-3 satellite of the Fifth Academy of Aerospace Science and Technology Group, is a witness of my country's navigation satellites from scratch. After tens of thousands of days and nights, he and his team successfully achieved thousands of breakthroughs in key technologies. As a result, the Beidou satellite navigation system can provide global users with all-weather, all-weather, high-precision positioning, navigation and timing services.
Chen Bin is the deputy chief designer of the Beidou-3 satellite control subsystem of the Fifth Academy of Aerospace Science and Technology Group. The control sub-system is the commander-in-chief of the satellite maintaining the correct orbit and the correct attitude in the sky. It collects the satellite's orbit and attitude information in real time, and once it finds a deviation, it will command the satellite to return to its normal state. Therefore, the moment Star Arrow separated, their work really began. At 9:43 on June 23, when the rocket soared into the sky and the fairing separated from the rocket, Chen Bin kept tugging his heart. He was waiting for the solar panel to open automatically. The satellite has a complete source of energy only after the solar panels are normally opened. For the previous 54 Beidou satellites, the deployment of solar panels requires human intervention on the ground to determine the working conditions and conditions before they can be deployed. The entire process takes 40 minutes. And this time, the satellite will unfold the solar panels autonomously for the first time, and the entire unfolding process will be completed within 2 minutes.
Chen Bin said that as the designer of the Beidou-3 control subsystem, they have to eliminate hundreds of possible problems and provide a variety of failure plans before the satellite is launched. On the table in Chen Bin's laboratory, there are a dozen products such as central management unit, sun sensor, gyroscope, etc., which are exactly the same as the control subsystem of the last Beidou-3 satellite. They are combined with the simulator to form the same operating environment as the Beidou-3. Not only can the feasibility of the failure plan be verified here, once there is any failure of the satellite during the flight, it can also be reproduced, found and solved immediately.
At 10:08 on June 23, 2020, 70 seconds after the separation of the stars and arrows, the solar panels unfolded on their own, and Chen Bin's heart that had been hanging was finally released.
With the stars and the moon, the wind and rain
There is such a group of people who are striving for the "Beidou"!
On the afternoon of June 30th, the final star of my country's Beidou-3 global navigation system passed 5 orbit changes, after 8 days of long-distance travel, and finally entered a 36,000-kilometer circular orbit and successfully fixed its position at the working orbit of 110.5°E. However, the closing star who successfully entered his job did not formally "start". At the same time, Nie Xin, the overall chief designer of the Beidou-3 satellite of the Fifth Academy of the Aerospace Science and Technology Group, is preparing with colleagues to conduct a comprehensive "physical examination" for the Beidou Final Star, which has just entered the scheduled orbit, to ensure that the final star is on. Under actual propagation conditions, the performance and signal of each channel are stable and normal.
Although the space is vast and vast, many frequencies and signal resources are limited in time. According to the standards of the International Civil Aviation Organization, the number of spreading codes applied by any country is time-limited. If it is not used before the specified date, there is a risk of being withdrawn. Nie Xin told the reporter of "Economic Half an Hour" that he was responsible for the overall control of the quality of more than a dozen systems and hundreds of single machines in the entire star of the "Ending Star", which made him feel unprecedented pressure. They need to race against time to ensure that the satellite reaches a specific orbital position within a specific time limit. From the beginning of the project, Nie Xin and the others sprinted at a speed of 100 meters to run this extraordinary marathon.
EMC, or electromagnetic compatibility, is one of the most concerned issues before satellite launch. Because once an electromagnetic compatibility problem occurs, it will affect the normal operation of the satellite in orbit, and the ground may receive wrong information or even lose information. In order not to make mistakes, Nie Xin and the others carried out thousands of analysis tests and solved difficult problems one after another.
At the time when the Beidou-3 "Ending Star" was the busiest and most critical point, Nie Xin's mother was seriously ill with lung cancer and urgently needed surgery. In order not to delay Nie Xin's work, the family did not tell Nie Xin's mother the specific time of the operation, until one day, he suddenly received a call from his wife.
Nie Xin
While worrying about his mother's body and worrying about the upcoming satellites on the other, Nie Xin couldn't sleep for several days. Fortunately, after treatment, his mother's body gradually improved, and he was relieved.
The long road to the Beidou, the support of family members and the full dedication of scientific researchers have allowed Xie Jun and Nie Xin, like thousands of Beidou people, to overcome obstacles and escort the Beidou satellite. The dream of Beidou is in the hands of a new generation of engineers. create. Nie Xin said that all navigation systems are compatible. The larger the number of Beidou satellites, the greater the weight in the positioning process, the more accurate the positioning accuracy it can provide. In a mobile phone application that can test real-time satellite signals, you can clearly see the Beidou navigation system in China, the GPS system in the United States, the GLONASS system in Russia, and the QZSS system of Japan's quasi-zenith satellite, and the BeiDou satellite has the largest number.
Statistics released by the Ministry of Transport show that at present, China has more than 6.6 million road operating vehicles, 51,000 postal express delivery vehicles, 1356 government ships of the Ministry of System, 8,600 water-assisted navigation facilities, and 109 coastal foundation reinforcement stations. , 300 general aircrafts have applied the Beidou system. The Beidou system was also installed on the first transport aircraft, achieving a zero breakthrough. The data disclosed in the "2020 China Satellite Navigation and Location Service Industry Development White Paper" shows that the overall output value of China's satellite navigation and location service industry reached 345 billion yuan in 2019, an increase of 14.4% over 2018, which is directly related to the development and application of satellite navigation technology The core output value of the industry is 116.6 billion yuan, accounting for 33.8% of the total output value. At present, domestic basic Beidou products have been exported to more than 120 countries and regions. With the completion of the global deployment of the Beidou satellite navigation system, the output value of my country's satellite navigation market is expected to exceed 430 billion yuan in the future.
[Half-Hour Observation] From being blank, to struggling to catch up, to standing side by side with the world's leading global navigation system, Beidou Wentian Road is condensed by the efforts of several generations of scientific researchers. On this rugged road, researchers have no shortcuts to take. They can only rely on their own hard work, independent innovation, and self-transcendence to blaze a unique path of exploration.
Beidou asks the sky and creates the soul