China builds laser communication ground station for massive satellite data transmission

A laser communication ground system with a 500mm-caliber antenna was successfully deployed Sunday on the Pamir Plateau in northwest China's Xinjiang Uygur Autonomous Region.

The system, developed by the Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences, marks the end of relying solely on microwave ground stations for satellite data reception. It is expected to significantly enhance the country's capacity for massive satellite data transmission.

With the rapid advancements in China's aerospace technology, the volume of data generated by satellite detection is growing exponentially. The current inability to transmit the massive amount of data promptly has become a significant problem, limiting the efficient utilization of China's space resources, said Li Yalin, a senior engineer of AIR.

Satellite-to-ground laser communications have abundant spectrum resources and a wider bandwidth, about 10 times to nearly 1,000 times wider than that of microwave communications. Additionally, this equipment is lighter, the system size is smaller, and it has lower power consumption. Li said it can address the growing demand for efficient and reliable transmission of information gathered by satellites.

However, weather conditions and atmospheric turbulence significantly affect the performance and availability of space-to-ground laser communications. Therefore, selecting an appropriate site can greatly mitigate the impact of complex and unstable atmospheric conditions.

The atmospheric conditions in the Mount Muztagata region on the Pamir Plateau are excellent, with high visibility and a dry and low rainfall climate, allowing for year-round space-to-ground laser communication operations, said Wang Jianping, another senior engineer of AIR and chief of the remote-sensing satellite ground station in Kashgar.

Facilities were constructed at 4,800 meters and 3,300 meters above the sea level, and the system will be operated remotely.

"Our team traveled about 300,000 kilometers on the Pamir Plateau to select the site of the station, and we faced tremendous difficulties," said Wang.

Recently, the project team successfully completed the first operational trial of daytime space-ground laser communications.

Huang Peng, a researcher with AIR and director of China Remote Sensing Satellite Ground Station, said the normalized operation of the newly built station will provide valuable engineering experience in satellite-ground laser communications, laying a solid foundation for planning China's next-generation massive satellite data transmission system.

AIR is planning and evaluating the feasibility of a laser communication ground station network to overcome the adverse weather conditions and improve the reliability of laser communications, according to Huang.