Table of Contents
ISRN Communications and Networking
Volume 2011, Article ID 239412, 9 pages
Research Article

Detector Design and Complexity Analysis for Cooperative Communications in Intersymbol Interference Fading Channels

Department of Electrical & Computer Engineering, Worcester Polytechnic Institute, Worcester, MA 01609, USA

Received 31 March 2011; Accepted 1 May 2011

Academic Editor: M. S. Hwang

Copyright © 2011 Yanjie Peng 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.


The area of cooperative communications has recently attracted lots of research interest because of the potential benefit of increased spatial diversity. In this paper, we study the detector design for cooperative communications in intersymbol interference (ISI) channels. A novel system framework employing nonorthogonal amplify-and-forward half-duplex relays through ISI channels is introduced. We focus on detector design and first consider an optimal detector that consists of a whitening filter and a maximum-likelihood sequence estimator (MLSE). However, such an optimal detector embedded with Viterbi algorithm has practical issues of high complexity if the relay period is long. Consequently, we adopt a multitrellis Viterbi algorithm (MVA) that reduces the complexity significantly but still achieves near-optimal performance. Simulation results demonstrate the performance of both the optimal and near-optimal detector designs.