Satellite constellations, whether for high-speed Internet access or for Earth observation using high-resolution imagery, are leading to a sharp increase in the volume of data to be brought back to Earth. To meet the needs of these very high-speed communication links, from 10 Gbps to 1 Tbps, optical technologies are becoming essential. Radio frequency technologies currently in use can no longer cope with such data rates without threatening the allocation of frequencies on Earth (5G-6G) or in space. However, to work at high debit rates, broadband optical communication systems require small detectors, high performance amplifiers or coherent modulation schemes needing high efficiency coupling into SMFs, which is subject to atmospheric turbulence. Using Cailabs' core technology, Multi-Plane Light Conversion (MPLC), followed by a photonic integrated chip optical recombiner, we have developed and qualified a unique component for turbulence compensation. This architecture provides high-speed turbulence mitigation at several kHz with the advantage of a single SMF output. In this paper, we investigate the fading improvement provided by this system over direct single mode fiber coupling under various environmental conditions and technical implementations. This system is tested on a km-long test link at Cailabs at up to 10 Gbps under appropriate environmental conditions and at higher debit rates on a turbulence emulation bench. Several configurations are evaluated, including several levels of turbulence. Meanwhile, Cailabs is building its first optical ground station for the LEO-ground optical link. We will present the first experimental results obtained and the roadmap for satellite-ground communication.
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