Analytic expressions are derived for the Wiener filter (WF), also known as the linear minimum mean square error (LMMSE) estimator, for an intensity-modulation/direct-detection (IM/DD) short-haul fiber-optic communication system. The link is purely dispersive and the nonlinear square-law detector (SLD) operates at the thermal noise limit. The achievable rates of geometrically shaped PAM constellations are substantially increased by taking the SLD into account as compared to a WF that ignores the SLD.
@article{arxiv.2004.12148,
title = {Wiener Filter for Short-Reach Fiber-Optic Links},
author = {Daniel Plabst and Francisco Javier García Gómez and Thomas Wiegart and Norbert Hanik},
journal= {arXiv preprint arXiv:2004.12148},
year = {2020}
}