Partial Feedback Impact On Achievable Rate Region In Multiple-Access Relay Channels

For discrete memoryless Slepian-Wolf multiple-access relay channel with relay-sources feedback (SW-MARC-RSF), an achievable rate region via partial decode and forward strategy at the relay is proposed, and by extending the results to the continuous alphabet version, the corresponding achievable rate region of the Gaussian SW-MARC-RSF is obtained. It is shown that our results include the important previous works on multiple-access channel (MAC) with feedback (Cover-Leung rate region) and without feedback (Slepian-Wolf [SW] rate region, etc) as special cases. Finally, through comparison of the achievable rate regions, with and without feedback, the impact of feedback on achievability is analyzed. The derived achievable rate region is shown to resolve the residual uncertainty at the receiver in an efficient way and demonstrates that in the partial decode and forward strategy, relay-sources feedback increases the achievable rate region in both discrete memoryless and Gaussian multiple-access relay channels.