Relay selection Algorithm for wireless cooperative networks: a learning‐based approach

Relay selection in cooperative communication is a crucial task for achieving the spatial diversity since the improper relay selection can decrease the overall capacity of the network. In this study, the authors use a reinforcement learning technique, called as Q ‐learning (QL), to solve the relay selection problem. They propose a ‘QL‐based relay selection algorithm’ (QL‐RSA) for wireless cooperative networks that maximises the total capacity of the network. QL‐RSA receives the reward (feedback) in terms of the capacity by learning a multi‐node amplify‐and‐forward cooperative environment with time‐varying Rayleigh fading channels. The advantages of QL‐RSA are that it is less complex, requires less channel feedback information and it is distributed in a multiple‐sources environment as it provides each source a self‐learning capability to find the optimal relay without exchanging information with other source nodes.