China sets new record with 120 Gbps satellite-to-ground laser transmission

The Aerospace Information Research Institute (AIR) of the Chinese Academy of Sciences has successfully achieved a peak transmission speed of 120 Gbps in a commercial experiment. This milestone involved a satellite-to-ground laser communications application with data rates surpassing 100 Gbps.

The results demonstrated a stable communication link and perfect data downlink quality. This landmark follows the team’s previous breakthroughs of 10 Gbps in 2023 and 60 Gbps in 2025, marking a leap in China’s capacity for operational satellite-to-ground laser communication.

The communication capacity of the AIRSAT-02 satellite’s laser payload was successfully doubled, increasing from 60 Gbps to 120 Gbps. This significant performance enhancement was achieved through on-orbit software reconfiguration, without requiring any hardware modifications to the satellite. The experiment utilized a self-developed 500 mm-aperture laser communication system at a ground station on the Pamir Plateau in northwest China’s Xinjiang Uyghur Autonomous Region, fully unlocking the payload’s potential.

This achievement establishes a new domestic record for the speed of satellite-to-ground laser communication. It successfully tackles major hurdles in ultra-high-speed links, specifically the need for rapid link setup, stable long-duration operation, and dependable, efficient data transmission.

The satellite and ground station achieved acquisition and link establishment within seconds during the experiment, with a success rate surpassing 93 percent. During the extended communication period, which lasted a maximum of 108 continuous seconds, a significant total of 12.656 terabits of data was successfully transmitted. The operation concluded with the successful reception and processing of high-quality remote sensing imagery.

The ground station used in this experiment is China’s first satellite-to-ground laser communication station to operate commercially and routinely. It has been operational since its completion in September 2024 and has since supported a number of missions.

Satellite-to-ground laser communication is widely considered the optimal solution for the ultra-high-speed transmission of massive spaceborne data. Ongoing operational validation signifies that the technology now possesses the core technical conditions and capabilities needed to support the downlink of large-scale space data in the future.