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arXiv · 2208.00836

Enhanced Atmospheric Turbulence Resiliency with Successive Interference Cancellation DSP in Mode Division Multiplexing Free-Space Optical Links

Yiming Li·Zhaozhong Chen·Zhouyi Hu·David M. Benton·Abdallah A. I. Ali·Mohammed Patel·Martin P. J. Lavery·Andrew D. Ellis
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Abstract

We experimentally demonstrate the enhanced atmospheric turbulence resiliency in a 137.8 Gbit/s/mode mode-division multiplexing free-space optical communication link through the application of a successive interference cancellation digital signal processing algorithm. The turbulence resiliency is further enhanced through redundant receive channels in the mode-division multiplexing link. The proof of concept demonstration is performed using commercially available mode-selective photonic lanterns, a commercial transponder, and a spatial light modulator based turbulence emulator. In this link, 5 spatial modes with each mode carrying 34.46 GBaud dual-polarization quadrature phase shift keying signals are successfully transmitted with an average bit error rate lower than the hard-decision forward error correction limit. As a result, we achieved a record-high mode- and polarization-division multiplexing channel number of 10, a record-high line rate of 689.23 Gbit/s, and a record-high net spectral efficiency of 13.9 bit/s/Hz in emulated turbulent links in a mode-division multiplexing free-space optical system.

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Yiming Li, Zhaozhong Chen, Zhouyi Hu, David M. Benton, Abdallah A. I. Ali, Mohammed Patel, Martin P. J. Lavery, Andrew D. Ellis. 2022-07-19. Enhanced Atmospheric Turbulence Resiliency with Successive Interference Cancellation DSP in Mode Division Multiplexing Free-Space Optical Links. https://doi.org/10.1109/jlt.2022.3209092

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