A Relay Selection Scheme for the Downlink of Cellular Networks

In cellular networks, the relay selection scheme for a given user is generally determined by the base station in a centralized manner. But the feedback for achieving every channel gain can cause a lot of burden to the system. In order to overcome this shortcoming, we propose a threshold-based relay selection scheme. In the proposed scheme, the feasibility of every relay node can be determined by itself according to the threshold, and the final decision on the relay selection among multiple feasible nodes is made by the source node. Simulation results show that the proposed scheme can provide comparable average mutual information with that of the centralized relay selection scheme, but with greatly lower computational complexity.