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arXiv · 2106.09464

Free space optical communication receiver based on a spatial demultiplexer and a photonic integrated coherent combining circuit

Vincent Billault·Jerome Bourderionnet·Jean-Paul Mazellier·Luc Leviandier·Patrick Feneyrou·Anaelle Maho·Michel Sotom·Xavier Normandin·Herve Lonjaret·Arnaud Brignon
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Abstract

Atmospheric turbulences can generate scintillation or beam wandering phenomena that impairs free space optical (FSO) communication. In this paper, we propose and demonstrate a proof-of-concept FSO communication receiver based on a spatial demultiplexer and a photonic integrated circuit coherent combiner. The system collects the light from several Hermite Gauss spatial modes and coherently combine on chip the energy from the different modes into a single output. The FSO receiver is characterized with a wavefront emulator bench that generates arbitrary phase and intensity patterns. The multimode receiver presents a strong resilience to wavefront distortions, compared to a monomode FSO receiver. The system is then used to detect a modulation of the optical beam through a random wavefront profile.

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Vincent Billault, Jerome Bourderionnet, Jean-Paul Mazellier, Luc Leviandier, Patrick Feneyrou, Anaelle Maho, Michel Sotom, Xavier Normandin, Herve Lonjaret, Arnaud Brignon. 2021-06-07. Free space optical communication receiver based on a spatial demultiplexer and a photonic integrated coherent combining circuit. https://doi.org/10.1364/oe.433087

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