Multi-Aperture Ground Receiver to Enhance Adaptive Optics Corrected GEO-Feeder Uplinks

We are interested in this paper to GEO-Feeder optical uplink. We consider a two ground apertures system and propose a phase estimation method at the point-ahead angle for adaptive optics pre-compensated ground to GEO satellite links based on downlink phase and log-amplitude measurements on the two ground apertures. This approach greatly improves the pre-compensation phase, especially decreasing the tip and tilt error by ~60%. It also improves the uplink coupled flux and fading statistics, decreasing the mean fade time duration by at least a factor two. It shows to perform better than the one aperture phase estimation scheme, especially in very severe atmospheric turbulence conditions. This method allows to make the GEO-Feeder telecommunication uplink reliable while using less power at the emission and shorter interleavers compared with the classical pre-compensation case.