Optimized Distributed BLAST for Cooperative Relay Networks

In this paper, we introduce optimized distributed bell laboratory layered space-time (OD-BLAST) for cooperative communication in wireless relay networks. Every potential relay node is equipped with a signal antenna, and the set of cooperating nodes is a priori unknown. In order to avoid the centralized stream and pilot allocation between cooperating nodes, a fixed signature vector (SV) is assigned for each potential relay node in the network. We analyze the constraints on the proposed schemes, and derive an optimization criterion for the SVs. A numerical method for SV design is provided and compared with randomly generated SVs. Simulation results confirm that the performance loss of OD-BLAST compared to centralized distributed BLAST is small for large number of cooperative relay nodes.