Distributed Space Time Codes for the Amplify-and-Forward Multiple-Access Relay Channel

TL;DR

This paper introduces a new family of space-time block codes for a multi-user relay channel, demonstrating optimality and significant performance gains over traditional orthogonal schemes through theoretical analysis and numerical results.

Contribution

It presents a novel construction of space-time codes for multi-user relay channels, proving their optimality and outperforming existing orthogonal transmission schemes.

Findings

Proposed codes are optimal in the diversity-multiplexing tradeoff.

New scheme outperforms orthogonal schemes like time sharing.

Numerical results confirm significant performance gains.

Abstract

In this work, we present a construction of a family of space-time block codes for a Multi-Access Amplify-and- Forward Relay channel with two users and a single half-duplex relay. It is assumed that there is no Channel Side Information at the transmitters and that they are not allowed to cooperate together. Using the Diversity Multiplexing Tradeoff as a tool to evaluate the performance, we prove that the proposed scheme is optimal in some sense. Moreover, we provide numerical results which show that the new scheme outperforms the orthogonal transmission scheme, e. g. time sharing and offers a significant gain.