A Full-Diversity Distributed Space-Time Coding System with Regenerative Relays

Abstract

We propose a distributed space-time coding (DSTC) systems based on the Alamouti design. We discuss the limitations in the relay channel of the "out of the box" Alamouti scheme and the additional complexity required to overcome its loss of diversity. Using a bit error rate based antenna selection approach, we design DSTC systems with one regenerative relay that improve on the classical Alamouti scheme when utilized in a two-hop channel. We prove that the proposed one relay DSTC system collects the full diversity of the distributed MISO channel. We also introduce a less complex DSTC system in which the relaying energies depend on the error probabilities at the relays. Numerical results show that the proposed systems perform close to the error probability lower bound obtained by considering error-free reception at the relays