The polling relay selection strategy based on the optimal stopping theory

Relay selection is a practical and effective way to improve the spectrum efficiency. However, most of the existing research about the relay selection is developed under the perfect instance channel state information (CSI) assumption. This premise limited the real application of relay selection. Fortunately, with the development of optimal stopping (OS) theory, we have a new way to overcome this shortage. In this paper, a polling relay selection strategy (PRSS) for the amplify-and-forward (AF) relay assisted (RA) network is proposed and analyzed. And, the OS theory is also investigated to cooperate with PRSS under the statistical CSI assumption. The simulation results show that PRSS with OS theory can improve the performance of AF RA network effectively.