Coupling of atmospheric perturbed optical beams with guided modes of propagation

Luca Rinaldi (1) , Vincent Michau (1) , Mathieu Boutillier (2)

1 DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon]
2 CNES - Centre National d'Études Spatiales [Toulouse]

Optical satellite-to-ground communications are disrupted by the effects of atmospheric turbulence which causes scintillation and phase distortion. By correcting the wave phase perturbations, adaptive optics allows the beam to be coupled into a single-mode optical fiber at reception with minimal fading. When the satellite is close to zenith, the scintillation rate is a few percent: conventional adaptive optics techniques are well suited. On the other hand, when the satellite elevation is low, the scintillation is high and conventional wavefront measurement techniques are no longer usable. We propose here a new approach to couple an incoming beam disturbed by turbulence with a set of propagation modes representative of a spatial multiplexer, including in the case of strong scintillation. We illustrate our approach by considering the case of the Laguerre-Gauss modes.

Mots clés: Adaptive optics; laguerre-gaussian modes; free-space optical communications; atmospheric turbulence

Domaines: Sciences de l'ingénieur [physics]; Physique [physics]

Luca Rinaldi, Vincent Michau, Mathieu Boutillier. Coupling of atmospheric perturbed optical beams with guided modes of propagation. COAT-2019 - workshop (Communications and Observations through Atmospheric Turbulence: characterization and mitigation), ONERA, Dec 2019, Châtillon, France. ⟨10.34693/COAT2019-S4-004⟩. ⟨hal-03146222⟩