Chen Fangyun

Chen Fangyun ( Chinese  陳芳允  /  陈芳允 , Pinyin Chén Fāngyǔn , born April 3, 1916 in Huangyan , † April 29, 2000 in Beijing ) was a Chinese communications engineer. He developed the orbit tracking, telemetry and control systems for the first Chinese satellites, was the father of the Beidou satellite navigation system and one of the initiators of the National High Technology Development Program . On September 18, 1999, he was awarded the Order of Merit "Two Bombs, One Satellite" (两弹一星 功勋 奖章).

Youth and Studies

Chen Fangyun was born on April 3, 1916 in Huangyan , now a township of Taizhou , Zhejiang Province , to an officer's son. At the age of five he started attending a private one-class school (私塾). The following year his mother died. It was not until 1928 that he started high school, graduated from Huangyan County High School and, from 1931, high school from Pudong High School , Shanghai . In 1934 he passed the entrance exam for Tsinghua University in Beijing, where he first studied mechanical engineering, then physics.

After the Marco Polo Bridge incident on July 7, 1937, Tsinghua University, together with Peking University and Nankai University , Tianjin , were relocated to the relatively safe Kunming , where they formed the United Southwest University . At that time, Ren Zhigong (任 之 恭, 1906–1995) and Meng Zhaoying (孟昭英, 1906–1995) taught communications engineering at the Faculty of Physics, with the lectures in applied communications engineering particularly arousing Chen Fangyun's interest. After graduating in 1938, he stayed at the United Southwest University on the suggestion and recommendation of Ren Zhigong and taught there at the Institute of Telecommunications for Radio Telecommunications.

Early developer work

Chen Fangyun later worked at the Radio Technology Factory of the Chengdu Aviation Commission . There he developed a radio direction finder, whereupon he was promoted to head of the research department and worked on navigation systems installed in aircraft. At the beginning of 1945, Chen Fangyun went to England to work in the research department of the electronics manufacturer AC Cossor Ltd. to work. First he worked on the development of circuits for color TVs at the London site ( AC Cossor had already brought the first black and white TV on the market in 1936), then he worked in the radar laboratory of the Manchester factory on the development and construction of radar devices for ships.

In May 1948, Chen Fangyun returned to China, where he initially worked at the Shanghai Institute of Physiology and Biochemistry on measuring nerve currents. The institute was subordinated to the Chinese Academy of Sciences as a branch institute in March 1950 . In 1951 he joined the Society of September 3 , a political party that represented the interests of academics. In 1953, Chen Fangyun was transferred to Beijing, where he worked on behalf of Academy Vice President Wu Youxun in the planning work for the establishment of the Institute for Electronics of the Academy of Sciences (中国科学院 电子 学 研究所). In 1955 he was promoted to the science council with the rank of professor (研究员) and began to work there after the establishment of the institute in 1956 as head of the 4th laboratory (第四 研究室), where one dealt primarily with the development of integrated circuits .

Space travel

When the Soviet Union launched the first artificial earth satellite Sputnik 1 on October 4, 1957 , Chen Fangyun carried out measurements of the Doppler shift of the carrier wave on the satellite transmitting on the known frequencies of 20.005 MHz and 40.002 MHz , which he used to determine the speed of the satellite and thus could calculate the orbital elements . After three weeks the batteries of the satellite were exhausted, and the further orbit observation took place with optical telescopes, in China from November 1957 through the "Satellite observation network of the Chinese Academy of Sciences" (中国 人造卫星 观测 网络, Pinyin Zhōnggúo Rénzào Wèixīng Guāncè Wǎngluò ) . From 1958 he supported Wang Shouguan (王 绶 琯, * 1923) from the newly founded Beijing Astronomical Observatory in setting up radio astronomical research in China. In that year he also began to develop a measuring device for short radio flashes in the nanosecond range. In 1963 he was able to manufacture the world's first device of this type. Based on the principles of this device, he had also developed a multi-channel pulse measuring device from 1960, which he made available to the Lop Nor nuclear weapons test site , where it was used on October 16, 1964 to measure the strength of the detonation of the first Chinese atomic bomb.

After Prime Minister Zhou Enlai and Vice Prime Minister Nie Rongzhen , the chairman of the Defense Technology Commission of the People's Liberation Army , approved written applications from Zhao Jiuzhang and Qian Xuesen to build a Chinese satellite in early 1965 , the Academy of Sciences first set up the "651 Project Planning Institute" ("651 ”设计院), the following year the“ Project Office 701 ”(“ 701 ”工程 处), which was supposed to deal specifically with tracking the orbit of the satellite later called Dong Fang Hong I. Astronomers, optics experts and electrical engineers worked there, including Chen Fangyun. In 1966, Project Office 701 was taken over by the Defense Technology Commission. The status of the scientists was ambivalent: half soldiers (which protected them from attacks by the Red Guards ), half civilians. When Chen Fangyun for "1967 Unit 436 " of the People's Liberation Army in Weinan was transferred, the nucleus of today's satellite control center Xi'an , he wore a blue Sun Yat-sen suit , and he neither rank (which had been abolished in 1965) nor official position had , he was simply addressed by the soldiers as an “honorable master” (老师傅).

In Weinan he was responsible for the trajectory monitoring systems of the satellite under construction, whereby he was able to fall back on his experience in determining the orbit parameters of Sputnik 1 - after the launch of the satellite on April 24, 1970, Doppler measuring devices were used again. This was not without controversy. The USA and the Soviet Union were already using long base interferometry (VLBI) to determine the position of their satellites. When the Chinese Academy of Sciences held a major meeting in late 1965 to discuss the orbit tracking methods to be used, the only thing that everyone agreed on was that the Academy's satellite observation network, established in 1957, should be incorporated into Project 651. However, the observatories on this network used optical theodolites , which required a cloud-free sky. The present project of national importance did not want to rely on it. The astronomers attending the meeting insisted that VLBI was the best system currently available. The electrical engineers wanted to use radar, and Chen Fangyun, who wanted to keep things as simple as possible given China's options at the time, advocated Doppler measurement. In the end, it was agreed that the point at which the satellite swings into orbit should be determined optically as well as with radar and Doppler devices to be on the safe side. From the second round, a VLBI system with one antenna each in Nanning and one in Kashgar should be tested.

Dong Fang Hong I was an automatic satellite. After he detached himself from the launcher, the antennas unfolded and the tape recorder on board began to play the song " The East is Red ". In the next step, a satellite returning to Earth, called 返回 式 卫星 (Pinyin Fǎnhuí Shì Wèixīng ) or "FSW" in China , control commands from Earth were necessary, as were geostationary communications satellites , where two orbit maneuvers were necessary to get around them to position after takeoff in the desired orbit over the equator. In connection with the Shuguang project for a manned space flight that began in 1970 , Chen Fangyun had studied the "Unified S-Band", which was first used in the American Apollo program , in which telemetry, voice communication and control signals are transmitted on a single carrier wave in the S-band were. The Shuguang project ended in 1972, but Chen Fangyun was of the opinion that the USB principle would also be suitable for satellites. Together with a few colleagues, he designed a corresponding system. The Jiuquan Cosmodrome Chief of Staff supported the plan, and when Chen Fangyun submitted the formal application to the People's Liberation Army Defense Technology Commission to build such a system , he found approval from both Qian Xuesen, then vice-chairman of the commission, and Sun Jiadong (孙家栋, * 1929), the chief designer of the satellites: By combining all TT&C functions on one carrier wave, only one antenna was needed for the satellite, which meant a considerable saving in weight.

National program for the development of high technology

On March 23, 1983 US President announced Ronald Reagan , the Strategic Defense Initiative at the United States, which provided for the establishment of a defense shield against intercontinental ballistic missiles. The European Research Coordination Agency EUREKA was founded in Paris on July 17, 1985 , followed by similar initiatives at the Council for Mutual Economic Assistance and in Japan . Under the influence of these events, the Chinese scholars found that China should not stand back. Chen Fangyun, nuclear physicist Wang Ganchang , satellite engineer Yang Jiachi (杨嘉 墀, 1919-2006) and laser pioneer Wang Daheng (王大珩, 1915-2011) proposed in a joint letter to the Chinese government on March 3, 1986 that China, in order to achieve international standards, should promote the development of domestic high technology. Deng Xiaoping , then chairman of the Central Military Commission , supported the proposal, whereupon the State Council of the People's Republic of China launched the “National Program for the Development of High Technology”, also known as “ Program 863 ” after the founding date . For the first 15 years, 10 billion yuan was made available to support projects in the 7 fields of biotechnology, space travel, information technology, lasers, automation, energy and materials science. By 2010, an economic value of 56 billion yuan was directly generated from the total of 5,200 funded projects; with secondary effects, the economic benefit was 200 billion yuan. "Program 863" is still in force today.

Positioning system

After the USA launched the first GPS satellite in 1978 and the Soviet Union launched the first three GLONASS satellites in 1982 , Chen Fangyun also started thinking about a satellite-based navigation system. In 1983, he suggested to some employees to use two geostationary satellites for this purpose. The working title of the project was "Dual Satellite Positioning System" (双星 定位 系统, Pinyin Shuāngxīng Dìngwèi Xìtǒng ). In contrast to the USA and the Soviet Union, where a system with numerous satellites was planned from the outset, Chen Fangyun and his colleagues designed a system that only required two satellites and a ground station in view of China's then still limited economic possibilities: the The ground station sends a signal via the satellites to the user's device and this sends a response signal via the satellites back to the ground station, where the position of the user is determined from the different transit time delays in both satellites, which in turn is communicated to the user via the satellites.

In April 1985, Chen Fangyun publicly presented this concept at a conference, in March 1986 a preliminary application was made to develop the dual satellite positioning system, and in April 1986 a feasibility assessment meeting was held. Three central questions emerged:

• Why do we need this dual satellite positioning system when the GPS system is ready?
• Is the system feasible with our technology level?
• Can we finance it?

Apart from the advantage that the dual satellite positioning system, unlike GPS, would also allow the transmission of short text messages, the meeting participants agreed after a heated discussion that it was important from a geostrategic point of view and to ensure the safety of the country to have a separate navigation system to develop. 17 sub-projects were defined, Sun Jiadong was appointed chief designer of the satellites, and Chen Fangyun - at the age of 70 - chief designer of the electronic systems.

Chen Fangyun died on April 29, 2000 and was unable to see the launch of the first Chinese navigation satellite - the system was later expanded to include several satellites and called Beidou - on October 30, 2000.

Web links

• Works by Chen Fangyun in the Chinese National Library (Chinese)
• Official website of "Program 863" (Chinese)

Individual evidence

1. ↑ 著名 科学家 陈芳允 逝世. In: peopledaily.com.cn. May 9, 2000, Retrieved August 29, 2019 (Chinese). 
2. ↑ 著名 无线电 电子 专家 陈芳允. In: gov.cn. September 26, 2007, Retrieved August 29, 2019 (Chinese). 
3. ↑ 历任 领导. In: ie.cas.cn. Retrieved August 29, 2019 (Chinese). 
4. ↑ At the time, the Academy each had its own institute for semiconductors, computers and automation.
5. ^ History. In: english.xao.ac.cn/. Retrieved on August 29, 2019 . 
6. ↑ Chen Fangyun did not officially join the People's Liberation Army until 1975, when he was almost 60 years old.
7. ↑ 赵 九章. In: 93.gov.cn. August 23, 2018, accessed August 29, 2019 (Chinese). 
8. ↑ 陈芳允: 卫星 上天 ， 我们 测控. In: cas.cn. Retrieved August 30, 2019 (Chinese). 
9. ^ National High-tech R&D Program (863 Program). In: most.gov.cn. Retrieved September 1, 2019 . 
10. ↑ In 1986, a large bowl of beef noodle soup cost about 1 yuan.
11. ↑ In 2010, the bowl of noodle soup with beef cost about 4 yuan.
12. ↑ 趙竹青: 國家 863 計劃 項目 ： 簡介 和 出台 背景. In: scitech.people.com.cn. July 23, 2010, accessed August 31, 2019 (Chinese). 
13. ↑ 我 所 喜获 国家 科技部 863 计划 重大 项目 课题 2 项. In: iapcm.ac.cn. Retrieved September 8, 2019 (Chinese). 
14. ↑ 高性能 分离膜 材料 的 规模 化 关键 技术 取得 突破. In: most.gov.cn. September 1, 2017, Retrieved September 8, 2019 (Chinese). 
15. ↑ 探秘 中国 北斗 导航 卫星: 最高 机密 到 民用 历时 20 年. In: tech.sina.com.cn. June 20, 2011, accessed September 1, 2019 (Chinese). 
16. ↑ 伽利略 挂 了 ， 再次 肯定 了 “北斗 人” 当年 的 选择. In: guancha.cn. July 16, 2019, accessed September 1, 2019 (Chinese). 
17. ↑ Beidou in the Encyclopedia Astronautica , accessed on September 1, 2019 (English).

Note: This article places the family name before the person's first name. This is the usual order in Chinese. Chen is the family name here, Fangyun is the first name.