On the Kurtosis of Modulation Formats for Characterizing the Nonlinear Fiber Propagation

Knowing only two high-order statistical moments of modulation symbols, often represented by the fourth moment called "kurtosis", the overestimation of nonlinear interference (NLI) in a Gaussian noise (GN) model due to Gaussian signaling assumption can be corrected through an enhanced GN (E...

Full description

Saved in:
Bibliographic Details
Published in:Journal of lightwave technology 2022-06, Vol.40 (12), p.3739-3748
Main Authors: Cho, Junho, Tkach, Robert
Format: Article
Language:English
Subjects:
Bandwidth
Communications systems
Enhanced Gaussian noise model
Interference
Kurtosis
Length measurement
Modulation
nonlinear fiber propagation
Optical communication
Phase modulation
Power measurement
probabilistic constellation shaping
Quadrature amplitude modulation
Random noise
Statistical analysis
Symbols
Wavelength division multiplexing
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Knowing only two high-order statistical moments of modulation symbols, often represented by the fourth moment called "kurtosis", the overestimation of nonlinear interference (NLI) in a Gaussian noise (GN) model due to Gaussian signaling assumption can be corrected through an enhanced GN (EGN) model. However, in some modern optical communication systems where the transmitted modulation symbols are statistically correlated, such as in systems that use probabilistic constellation shaping (PCS) with finite-length sphere shaping, the kurtosis-based EGN model produces significant inaccuracies in analytical prediction of NLI. In this paper, we show that for correlated modulation symbols, the NLI can be more accurately estimated by substituting a statistical measure called windowed kurtosis into the EGN model, instead of the conventional kurtosis. Remarkably, the optimal window length for windowed kurtosis is found to be consistent with the self-phase modulation (SPM) and cross-phase modulation (XPM) characteristic times in various system configurations. The findings can be used in practice to analytically evaluate and design NLI-tolerant modulation formats.
ISSN:0733-8724
1558-2213
DOI:10.1109/JLT.2022.3152411