Efficient Power Allocation for Multiple Relays with Lossy Intra-Links and Distributed Source Coding

The so-called Chief Executive Officer problem has inspired some relay transmission schemes. It suggests that the source message can be recovered at the destination by combining a set of corrupted replicas sent by multiple relays, as long as the replicas are sufficiently correlated with the original message. In this work, we build on the Slepian-Wolf theorem to assess the outage performance of a distributed source coding scheme for a decode-and-forward multirelay system in which the direct link is unavailable to convey information. As in the CEO problem, the replicas forwarded by the relays are allowed to contain intralink errors due to previous unreliable hops, and the destination is expected to reconstruct the original message by jointly decoding all the received replicas. In addition to analyzing the outage probability of such scheme, we derive a simple yet efficient power allocation strategy for the multiple relays, which is asymptotically optimal at high signal-to-noise ratio.