Relay precoding strategy selection in cognitive MIMO relay networks with limited feedback

In this paper, we study the relay precoding strategy selection for cognitive multiple-input multiple-output (MIMO) relay networks using limited feedback quantized precoding technique. It is assumed that the codebook of each secondary relay node is locally designed. The problem is formulated as a potential game. Then, we analyze the property of the pure strategy Nash equilibrium of the proposed game. The feasibility of the pure strategy NE is also studied. Furthermore, we propose a best response dynamic algorithm to find the feasible pure strategy Nash equilibrium of the formulated game. Numerical results show that our proposed algorithm, whose convergence speed is very fast, can achieve satisfied performance.