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arXiv · 1506.02937

Stochastic Digital Backpropagation with Residual Memory Compensation

Naga V. Irukulapati·Domenico Marsella·Pontus Johannisson·Erik Agrell·Marco Secondini·Henk Wymeersch
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Abstract

Stochastic digital backpropagation (SDBP) is an extension of digital backpropagation (DBP) and is based on the maximum a posteriori principle. SDBP takes into account noise from the optical amplifiers in addition to handling deterministic linear and nonlinear impairments. The decisions in SDBP are taken on a symbol-by-symbol (SBS) basis, ignoring any residual memory, which may be present due to non-optimal processing in SDBP. In this paper, we extend SDBP to account for memory between symbols. In particular, two different methods are proposed: a Viterbi algorithm (VA) and a decision directed approach. Symbol error rate (SER) for memory-based SDBP is significantly lower than the previously proposed SBS-SDBP. For inline dispersion-managed links, the VA-SDBP has up to 10 and 14 times lower SER than DBP for QPSK and 16-QAM, respectively.

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Naga V. Irukulapati, Domenico Marsella, Pontus Johannisson, Erik Agrell, Marco Secondini, Henk Wymeersch. 2015-06-09. Stochastic Digital Backpropagation with Residual Memory Compensation. https://doi.org/10.1109/jlt.2015.2477462

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