MAXIMUM-LIKELIHOOD CHANNEL ESTIMATION IN PRESENCE OF IMPULSIVE NOISE FOR PLC SYSTEMS

Impulsive noise in power lines usually bears higher power spectral density than the background noise. Even a sample of such noise, if not mitigated, destroys symbols in all the subcarriers affecting channel estimation and information detection. In this paper, we study two maximum-likelihood approaches to estimate the channel in the presence of impulsive noise for an OFDM based PLC system. In both approaches, we approximate the impulsive noise first and use it to determine the channel frequency response. In the first approach, we assume the estimated noise to be random and perform the channel estimation assuming that its statistics are given. In the second approach, the impulsive noise is assumed to be deterministic and the channel frequency response is determined after proper subtraction from the observations. As will be shown by simulation results, the estimator that assumes noise to be random generally performs better than the one that treats the estimated impulsive noise as a deterministic quantity.Grant numbers : The work presented in this paper is supported by the Generalitat de Catalunya under grant 2014 SGR 1551 and 2014 SGR 1567.© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works