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arXiv · 1912.13436

30% Reach Increase via Low-complexity Hybrid HD/SD FEC and Nonlinearity-tolerant 4D Modulation

Gabriele Liga·Bin Chen·Sjoerd van der Heide·Alireza Sheikh·Menno van der Hout·Chigo Okonkwo·Alex Alvarado
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Abstract

Current optical coherent transponders technology is driving data rates towards 1 Tb/s/{\lambda}and beyond. This trend requires both high-performance coded modulation schemes and efficient implementation of the forward-error-correction (FEC) decoder. A possible solution to this problem is combining advanced multidimensional modulation formats with low-complexity hybrid HD/SD FEC decoders. Following this rationale, in this paper we combine two recently introduced coded modulation techniques:the geometrically-shaped 4D-64 polarization ring-switched and the soft-aided bit-marking-scaled reliability decoder. This joint scheme enabled us to experimentally demonstrate the transmission of 11x218 Gbit/s channels over transatlantic distances at 5.2bit/4D-sym. Furthermore, a 30% reach increase is demonstrated over PM-8QAM and conventional HD-FEC decoding for product codes.

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Gabriele Liga, Bin Chen, Sjoerd van der Heide, Alireza Sheikh, Menno van der Hout, Chigo Okonkwo, Alex Alvarado. 2019-12-31. 30% Reach Increase via Low-complexity Hybrid HD/SD FEC and Nonlinearity-tolerant 4D Modulation. https://doi.org/10.1109/lpt.2020.2995636

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