SpaceX’s Starlink operates at a much lower altitude, usually offering speeds in the tens, rather than hundreds, of megabits-per-second (Mbps) – with Starlink satellites reaching just beyond 200 Mbps. Achieving a full gigabit from 36,000 kilometers (over 22,000 miles) above Earth could signify a significant advancement in the physics and engineering concerning space-to-ground connections. Historically, the Earth’s atmosphere posed the greatest challenge to laser-based communications. Atmospheric turbulence alters, scatters, and distorts light, rendering high-speed laser downlinks exceptionally challenging. To address this, scientists devised a novel strategy termed AO-MDR synergy. This technique combines two cutting-edge approaches: Adaptive Optics, which rectifies signal distortion, and Mode Diversity Reception, which aids in re-capturing usable light when the signal is partially scattered.
The initiative is attributed to Professor Wu Jian from Peking University of Posts and Telecommunications and Liu Chao from the Chinese Academy of Sciences. Although the laser technology remains in its testing phase, it suggests a potential future where satellites transmit fiber-like speeds to Earth without the limitations of conventional radio frequency systems.
