Soft Decision Aided Suboptimal ML Detection Receiver for Clipped COFDM Transmissions

Abstract

A soft decision aided suboptimal maximum likelihood detection algorithm for clipped COFDM transmissions is presented. Then clipping mitigation is performed by means of an iterative fashion receiver. Here the goal is to provide a posteriori code word bits soft decision instead of observed channel signal correction. From the channel decoder output information, a reduced set of channel neighbour signals is built aiding the maximum likelihood-based detection. Furthermore, we investigate the receiver performance for both non-coded and coded transmission schemes as well as over a frequency-selective channel scenario. Numerical results show that the proposed receiver is able to perform very close to the linear case even at severe clipping ratio.