Comprehensive node selection and power allocation in multi-source cooperative mesh networks

This paper considers resource allocation with relay selection in a multi-source multi-destination mesh network wherein dedicated relay nodes use the decode-and-forward (DF) protocol. The key difference from previous work is that we consider resource allocation across the source-relay, relay-destination, and source-destination channels in a multi-source network. The solution to the related optimization problem simultaneously solves for relay selection, power allocation, and the cooperation strategy (direct transmission, if optimal, is a valid solution). Since the jointly optimal solution is of exponential complexity, we introduce a set of time-sharing factors and relax the selection constraint, resulting in an upper bound to the true solution. Imposing selection leads to a feasible, but tight, lower bound on the optimal solution. Second, we propose a decentralized selection and power allocation scheme. Simulation results show that the performance of the decentralized selection scheme almost exactly tracks that of the upper bound for both the max-sum and max-min rate metrics while offerring computational benefits.