On the Optimal Power Allocation in Relay Networks based on a Two-Stage Relaying Scheme

Abstract:
In this paper, we consider a wireless relay system consisting of one source node, some number of relay stations and one destination node. The relay nodes encode their received signals generating a distributed space-time code without decoding the received signal. For this system, we prove upper bounds on the pairwise error probability (PEP). After that, we focus on orthogonal space-time codes and analyze four different cooperation strategies depending on the activation modus of the source node and the destination node. Using an upper bound on the PEP, we analyze the optimal allocation of the total power budget to the source node and the to relay nodes for the four transmission strategies.