Table of Contents
ISRN Signal Processing
Volume 2011, Article ID 254597, 8 pages
http://dx.doi.org/10.5402/2011/254597
Research Article

Iterative Channel Estimation for Nonbinary LDPC-Coded OFDM Signals

Wireless Systems Engineering and Research (WISER) S.r.l., Via Fiume, 23, 57123 Livorno, Italy

Received 20 December 2010; Accepted 8 March 2011

Academic Editor: C. S. Lin

Copyright © 2011 Giacomo Bacci et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This work deals with the issue of channel estimation in the context of non-binary LDPC-coded OFDM systems over doubly selective multipath channels. In particular, we show how to derive an iterative Wiener-filter-based estimation method using both time and frequency channel correlation and considering the particular characteristics of the channel code. The proposed algorithm can use either soft information or hard decisions fed back by the decoder to refine the channel estimation, so as to improve the system performance at the expense of an increased receiver complexity. Simulation results under typical working conditions are presented to compare the performance of the proposed method with respect to classical techniques.