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Updated: Dec 21, 2025
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Published on: June 25, 2021
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Multimode communication through the turbulent atmosphere
Summary
Free-space optical communication can be enhanced by relating multiple-input-multiple-output (MIMO) and orbital angular momentum (OAM) modes. This study unifies these multiplexing schemes and analyzes atmospheric turbulence effects on communication modes.
Area of Science:
- Optical Communications
- Free-space Optics
- Information Transfer
Background:
- Improving information transfer in free-space optical communication is crucial.
- Multiplexing techniques like MIMO and OAM can increase channel capacity.
- Both MIMO and OAM modes are limited by aperture size and atmospheric turbulence.
Purpose of the Study:
- To demonstrate the close relationship between MIMO and OAM multiplexing schemes.
- To characterize the impact of atmospheric turbulence on communication modes.
- To unify MIMO and OAM approaches for enhanced free-space optical communication.
Main Methods:
- Singular value decomposition of the transfer matrix for MIMO modes.
- Utilizing Laguerre-Gauss vortex beams for OAM multiplexing.
- Employing the phase screen method to model atmospheric turbulence effects.
Main Results:
- MIMO and OAM multiplexing schemes are shown to be closely related for circular apertures.
- Optimal Laguerre-Gauss vortex beams for communication match MIMO singular vectors under specific conditions.
- Atmospheric turbulence significantly affects the usable communication modes.
Conclusions:
- The study unifies MIMO and OAM multiplexing, offering a more comprehensive understanding of free-space optical communication.
- The findings provide insights into optimizing mode selection for robust optical communication systems.
- Characterizing turbulence effects is essential for reliable free-space optical links.
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