This year marks a significant milestone as the BeiDou Satellite Navigation System celebrates its 30th anniversary. Today, the stable "China Coordinate" not only stands tall in space but also permeates our daily lives like water and electricity. How does this celestial BeiDou system integrate into our surroundings? What role does it play in our lives? Recently, the program "Kaijiangla" invited the chief designer of the BeiDou-3 satellite system, Lin Baojun, to provide a detailed interpretation of the BeiDou system that is closely related to us.

 
Ⅰ."BeiDou is like air, Imperceptible yet ubiquitous."

"When you stand still and look up, how many BeiDou satellites are above your head?"

In the program, Lin Baojun presented a distribution map showing 31 visible stars from the BeiDou system, which is more than the combined satellites of the other three major navigation systems: GPS, GLONASS, and Galileo. "The more visible stars there are, the faster the positioning speed and the higher the accuracy."

"Despite the abundance of visible stars, it seems difficult for us to notice them in daily life. In response, Lin Baojun remarked, 'The BeiDou system is like the air we breathe, indispensable yet imperceptible.'"

"The timely ringing of the morning alarm clock is made possible by the precise time synchronization of BeiDou and 5G; the closest shared bicycle downstairs, the optimal routes chosen by commuter buses, and the countdown prediction of traffic lights all rely on precise positioning and navigation provided by BeiDou. Moreover, during ticket snatch-ups at concerts and stock exchanges, BeiDou satellites are constantly providing precise timing services for them."

"In addition, BeiDou also deploys unique 36,000-kilometer-high geostationary satellites in the Asia-Pacific region. 'These satellites are positioned at a high altitude with a wide field of view, making it less likely for their signals to be obstructed by skyscrapers in urban areas. This results in better navigational availability and continuity compared to navigation systems in other countries. The enhanced user experience in car navigation systems nowadays can be attributed to this,' explained Lin Baojun."

Ⅱ."The 'BeiDou Enthusiast' behind the BeiDou Navigation System

From 'not being the bottom' to surpassing the former leader

Lin Baojun has a nickname, 'BeiDou Enthusiast.' 'Enthusiast' refers to his willingness to use new technologies, even those that have never been used in the world before."

"In the aerospace industry, there is an unwritten rule that no more than 30% of new technologies should be used in a spacecraft. However, during the development of the BeiDou-3 system, over 160 key technologies were incorporated, with an innovation level exceeding 70%. Many of these were entirely new to the world, and Lin Baojun implemented them in the design of the BeiDou-3 system."

"In his opinion, new technology does not equate to unreliability. If combined with mature components and processes, along with thorough testing, it is possible to overcome the challenges that cannot be learned, purchased, or bypassed."

In the early stages of the BeiDou system's design, the team set a goal of "not being at the bottom" - "when the young members of the team grow old, BeiDou can be on par with GPS, then our lives will not have been in vain."

However, as the BeiDou system reached its maturity, it surpassed its goals and even exceeded GPS in terms of performance. Lin Baojun proudly praised his team, saying, "When we launched the first satellite of BeiDou-3, 81 people, with an average age of 31, took three years and three months to accomplish what would have taken the GPS-2 to GPS-3 transition 20 years, and we did it all."

To enhance positioning accuracy, the BeiDou system development team independently developed higher-precision hydrogen atomic clocks based on rubidium atomic clocks. In order to ensure the optimal functioning of the clocks, they also invented a seamless switching technology. "When the hydrogen atomic clock and rubidium atomic clock work simultaneously, if the hydrogen atomic clock malfunctions, it can be seamlessly switched to the rubidium atomic clock within 20 picoseconds (one trillionth of a second), with virtually no user perception."

"Is matching the field of study important?"Lin Baojun speaks from experience

As the college entrance examination season and graduation season approach, many individuals who are about to choose their majors or seek employment may be concerned about the importance of "matching the field of study."

Is it really crucial for one's major to match their career? What happens if it doesn't? Appearing on the show, Lin Baojun, who changed majors with each academic promotion, provided his advice.

He emphasized that the most important factors are the methods of learning, interest in learning, and problem-solving skills. "Before the age of thirty, understanding what you want is already good. The darkness before dawn is the hardest to endure, so please hold on for one more second!"