94Ha Viewpoint
China has made a breakthrough in the field of satellite-to-ground laser communications, successfully completing the world’s first satellite-to-ground laser 100Gbps (gigabits per second) ultra-high-speed high-resolution remote sensing image transmission test, surpassing the Starlink system of SpaceX in this field.
According to reports from the Hong Kong South China Morning Post and the Beijing Daily client, Changguang Satellite Technology Co., Ltd. announced that the company used its self-developed vehicle-mounted laser communication ground station to conduct the first satellite-to-ground laser 100Gbps ultra-high-speed high-resolution remote sensing image transmission test with the “Jilin-1” platform 02A02 star-mounted laser terminal.
The company said that this achievement is 10 times the previous record and was completed between a truck carrying a ground station and the Jilin-1 constellation satellite. The report said that unlike conventional ground receiving devices, the Chinese team set up the observation station on a truck to make it mobile, which can speed up the application.
Wang Xingxing, technical director of Changguang Satellite Laser Communication Ground Station, said that this technology can increase the transmission rate to 100Gbps, “equivalent to transmitting 10 complete movies in one second”, marking an important step for China in the field of ultra-high-speed optical network transmission between satellites and the ground.
He said that although the Starlink system of Musk, the world’s richest man, has demonstrated the intersatellite laser communication system, it has not yet deployed satellite-to-ground laser communication.
According to reports, the Changguang Satellite team has successively overcome atmospheric channel compensation technology, high-precision time-frequency synchronization technology, Doppler frequency shift state correction technology, etc., and solved the problems of signal distortion caused by atmospheric turbulence, frequency drift caused by high-speed relative motion between satellites and the ground, weak light signal detection, and high-precision beam tracking.
It is reported that the laser communication device used in this test has been carried on the “Jilin-1” satellite constellation. The constellation currently has a total of 117 satellites in orbit, and plans to expand to 300 satellites by 2027, becoming the world’s largest sub-meter commercial remote sensing satellite constellation.
The application of new technologies will significantly improve the efficiency of data transmission, and will be used in the fields of national defense security, disaster monitoring, smart cities, etc., and provide technical support for the development of 6G.
The South China Morning Post reported that this breakthrough allowed China to surpass the United States in laser communication technology. Although Lockheed Martin and Verizon in the United States have cooperated to develop similar technologies, they can only achieve data transmission with a delay of 30 milliseconds within a distance of 100 meters.
