Chinese scientists have successfully conducted an experiment on laser communication between a satellite in geostationary orbit and a ground station, providing two-way data transfer at high speed 1 Gbit/s at a distance of more than 40 000 kilometers (slant range, usually, more than the height of the geostationary orbit). The successful conduct of this experiment by China paves the way for the creation of a new generation integrated earth-space network and the development of the deep space internet.
Laser communication at a distance 40 740 km
The experiment was implemented with the participation of the Chinese Academy of Sciences, Beijing University of Posts and Telecommunications та China Academy of Space Technology. Scientists have established a stable laser channel between an observatory in Yunnan province and a satellite in geostationary orbit.
The main achievements of the experiment:
distance — to 40 740 km;
transmission speed — 1 Gbps in both directions;
connection establishment time — 4 seconds;
continuous operation of the channel - over 3 years.
Research in the field of satellite-ground laser communication is developing in two key directions: increasing peak data transfer rates and ensuring long-term, stable, real-time two-way communication in high orbits. The second direction is especially important for satellites in geostationary orbit (GEO), which work at a height close to 36 000 km and are used for communication, surveillance and strategic tasks.
During the experiment, Chinese experts for the first time transferred the stability of the connection from the "minute" level to the "hour" level, which is considered a major technological leap. The conducted experiment means, that satellites in high orbit will be able to transmit large amounts of data at high speed, receive complex commands in real time, perform more intelligent data processing functions. This will allow Chinese scientists to gradually transform orbital vehicles from simple repeaters into full-fledged computing nodes of the space infrastructure.
A step towards lunar and martian connection:
The researchers emphasized, that the experiment confirmed the capabilities of ground stations to work with long-distance laser communication channels. In the future, such technologies can be used to create high-speed optical lines to the Moon, Mars, as well as to interplanetary probes of deep space.
The reliability and stability of the demonstrated system indicate the readiness of the technology for large-scale engineering implementation. The development of laser satellite communication is seen as a key element of future space networks for orbital infrastructure, support of autonomous missions, creation of high-speed space internet and ensuring the operation of satellite groups of the new generation.
Chinese experiment demonstrates increased competition in the field of space communications and acceleration of the transition from radio frequency to optical data transmission technologies.
https://www.chinadaily.com.cn/a/202603/04/WS69a7a006a310d6866eb3b91b.html