ETHZ > EE Dept > Comm Tech Lab > Comm Theory Group > Publications >

Space-time signal design for fading relay channels

Authors

Rohit U. Nabar and Helmut Bölcskei

Reference

Proc. of IEEE Global Telecommunications Conference (GLOBECOM), San Francisco, CA, Vol. 4, pp. 1952-1956, Dec. 2003

DOI: 10.1109/GLOCOM.2003.1258578

[BibTeX, LaTeX, and HTML Reference]

Abstract

Cooperative diversity is a transmission technique where multiple users pool their resources to form a virtual antenna array that realizes spatial diversity gain in a distributed fashion. In this paper, we examine space-time signal design for a simple amplify-and-forward relay channel. We show that the code design criteria for the relay case consist of the traditional rank and determinant criteria as well as appropriate power control rules. While proper signal design and power control can indeed achieve full spatial diversity gain, the potential benefit of relay-assisted communication over direct communication depends strongly on the channel conditions. In particular, we present a switching criterion based on which the source terminal may opt to forego relay-assisted communication and communicate with the destination terminal directly. The criterion is based on the cut-off rate of the effective channel (physical channel in conjunction with finite constellation and maximum-likelihood (ML) decoding).

Keywords

Relay channels, cooperative diversity, protocols

Download this document:

Copyright Notice: © 2003 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.