Optimal and suboptimal relay selection and power allocation in multi-relay cooperative network

We study a cooperative communication scenario where multiple amplify-and-forward relays cooperate to transmit data from a source to destination. We discuss an optimal power allocation method to assign transmit powers to the source and relays in order to maximize achievable data rate of the system.We also propose less-complex suboptimal power allocation methods using various relay selection strategies. We provide simulation results to demonstrate performance of the optimal power allocation and suboptimal relay selection and power allocation schemes. We show that these suboptimal schemes perform close to optimal scheme and are more reasonable for practical implementation.