We propose the use of orbital angular momentum (OAM) states to form modulation symbols in a free-space laser communication link affected by atmospheric turbulence. A collection of superpositions of 2 and 4 active OAM modes are used for transmitting digital information. To sense and decode the data we compare three candidate architectures, based on a Mode Sorter, a Shack-Hartmann and phase flattening holograms. In this work we use concepts of Optimal Transport, particularly the Wasserstein distance and barycenter, for an optimal selection of OAM superpositions and a more appropriate processing of OAM spectra, leading to more accurate detection, achieving a classification error smaller than 1/1000 in intermediate to strong turbulence conditions.
|Title of host publication||Laser Communication and Propagation through the Atmosphere and Oceans XI|
|Editors||Jaime A. Anguita, Jeremy P. Bos, David T. Wayne|
|State||Published - 2022|
|Event||Laser Communication and Propagation through the Atmosphere and Oceans XI 2022 - San Diego, United States|
Duration: 22 Aug 2022 → 23 Aug 2022
|Name||Proceedings of SPIE - The International Society for Optical Engineering|
|Conference||Laser Communication and Propagation through the Atmosphere and Oceans XI 2022|
|Period||22/08/22 → 23/08/22|
Bibliographical noteFunding Information:
This work was supported by CONICYT-Chile (FR-1210297) and by ANID gram ICN17-012.
© 2022 SPIE.
- FSO communications
- optimal transport
- orbital angular momentum
- turbulence-induced distortions
- Wasserstein distance