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arXiv · 1804.02263

Iterative Detection and Phase-Noise Compensation for Coded Multichannel Optical Transmission

Arni F. Alfredsson·Erik Agrell·Henk Wymeersch
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Abstract

The problem of phase-noise compensation for correlated phase noise in coded multichannel optical transmission is investigated. To that end, a simple multichannel phase-noise model is considered and the maximum a posteriori detector for this model is approximated using two frameworks, namely factor graphs (FGs) combined with the sum-product algorithm (SPA), and a variational Bayesian (VB) inference method. The resulting pilot-aided algorithms perform iterative phase-noise compensation in cooperation with a decoder, using extended Kalman smoothing to estimate the a posteriori phase-noise distribution jointly for all channels. The system model and the proposed algorithms are verified using experimental data obtained from space-division multiplexed multicore-fiber transmission. Through Monte Carlo simulations, the algorithms are further evaluated in terms of phase-noise tolerance for coded transmission. It is observed that they significantly outperform the conventional approach to phase-noise compensation in the optical literature. Moreover, the FG/SPA framework performs similarly or better than the VB framework in terms of phase-noise tolerance of the resulting algorithms, for a slightly higher computational complexity.

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Arni F. Alfredsson, Erik Agrell, Henk Wymeersch. 2018-04-06. Iterative Detection and Phase-Noise Compensation for Coded Multichannel Optical Transmission. https://doi.org/10.1109/tcomm.2019.2912569

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