Energy-efficient cooperative relay selection scheme in MIMO relay cellular networks

Power saving is an important issue in wireless networks. This paper proposed an energy-efficient cooperative relay selection scheme that utilized the transmission power more efficiently in cooperative relaying systems. The nodes in the network were deployed with multiple antennas and the decode-and-forward relaying protocol was used. The optimization problem of energy efficiency in cooperative relaying was defined. Based on a suboptimal solution, the energy-efficient relay selection scheme was given, which selected the relay stations with the best energy efficiency and decided the optimal number of cooperative relay stations. Compared with the fixed relay cooperation, the simulation results showed that the proposed scheme could improve the energy efficiency as well as the system capacity, irrespective of the channel state conditions. It could be concluded that the proposed cooperative relay selection scheme improved the radio resource efficiency effectively.