A Study on Source-Relay Cooperation for the Outage-constrained Relay Channel

We study the influence of source-relay cooperation on the outage-constrained capacity bounds of the Gaussian relay channel. As was observed, coherent source-relay transmission does not lead to improvement for the decode and forward (DF) achievable rate in the presence of Rayleigh fading. We show that this is in sharp contrast to the case with known channel means. Then, transmission gains highly from coherent source-relay to destination transmission.