Nonlinearity Mitigation in WDM Systems: Models, Strategies, and Achievable Rates
Journal article, 2019

After reviewing models and mitigation strategies for interchannel nonlinear interference (NLI), we study its characteristics and coherence properties. Based on this study, we devise an NLI mitigation strategy, which exploits the synergic effect of phase and polarization noise (PPN) compensation and subcarrier multiplexing with symbol-rate optimization. This synergy persists even for high-order modulation alphabets and Gaussian symbols. A particle method for the computation of the resulting achievable information rate and spectral efficiency (SE) is presented and employed to lower-bound the channel capacity. The dependence of the SE on the link length, amplifier spacing, and presence or absence of in-line dispersion compensation is studied. Single-polarization and dual-polarization scenarios with either independent or joint processing of the two polarizations are considered. Numerical results show that, in links with ideal distributed amplification, an SE gain of about 1 bit/s/Hz/polarization can be obtained (or, in alternative, the system reach can be doubled at a given SE) with respect to single-carrier systems without PPN mitigation. The gain is lower with lumped amplification, increases with the number of spans, decreases with the span length, and is further reduced by in-line dispersion compensation. For instance, considering a dispersion-unmanaged link with lumped amplification and an amplifier spacing of 60 km, the SE after 80 spans can be be increased from 4.5 to 4.8 bit/s/Hz/polarization, or the reach raised up to 100 spans (+25%) for a fixed SE.

optical fiber communication

Achievable information rate

nonlinearity mitigation

hidden Markov models

perturbation methods

Author

M. Secondini

Sant'Anna School of Advanced Studies (SSSUP)

National Excellence Center for Photonic Networks

Erik Agrell

Chalmers, Electrical Engineering

E. Forestieri

Sant'Anna School of Advanced Studies (SSSUP)

National Excellence Center for Photonic Networks

D. Marsella

Nokia

Menelaos Ralli Camara

Sant'Anna School of Advanced Studies (SSSUP)

National Excellence Center for Photonic Networks

Journal of Lightwave Technology

0733-8724 (ISSN) 1558-2213 (eISSN)

Vol. 37 10 2270-2283 8653853

Subject Categories

Telecommunications

Communication Systems

Signal Processing

DOI

10.1109/JLT.2019.2901908

More information

Latest update

2/7/2020 1