China achieves breakthrough in high-orbit satellite-ground laser communication

BEIJING -- Chinese research institutions have successfully conducted a laser communication experiment between a high-orbit satellite and the ground, achieving two-way data transmission at 1 gigabit per second over a distance exceeding 40,000 kilometers, the China Science Daily reported on Tuesday.

The current research on satellite-ground laser communication is advancing in two main directions. One is the pursuit of downlink peak rates to meet the demand of data surges in specific scenarios. The other is the enhancement of long-duration, stable, two-way and real-time communication capabilities in high-orbit environments, which are the foundations of space-based systems and advanced interactive applications.

The Chinese Academy of Sciences' Institute of Optics and Electronics, in collaboration with the Beijing University of Posts and Telecommunications, the China Academy of Space Technology and other institutions, has established a stable laser link between an observatory in Southwest China's Yunnan province and a geosynchronous satellite.

At distances of up to 40,740 kilometers, they achieved both uplink and downlink two-way communication at the high speed of 1 gigabit per second, setting records of 4 seconds for rapid link establishment and over 3 hours for uninterrupted link duration.

The experiment, conducted on the more challenging high-orbit platform, extended stable communication duration from the minute level to the hour level and ensured two-way, high-speed, real-time communication capabilities. This marks a critical step toward an integrated earth-space network in the future.

The breakthrough means that satellites can now not only transmit data at high speeds but also receive complex commands in real time, laying a foundation for upgrading high-orbit satellites from data relay stations into intelligent processing hubs.

Researchers noted that the experiment also validated the deep-space communication capabilities of ground stations, paving the way for establishing high-speed laser links with moon, Mars and distant space probes in the future. The demonstrated reliability indicates that the relevant technologies offer a mature engineering model for future large-scale applications.