Relay Selection Based on Residual Energy of Node and Power Allocation

This paper studies joint optimization strategy of relay selection and power allocation in a decoded forwarding (DF) protocol. The strategy first proposes a cooperative relay node selection algorithm based on residual energy (RE), and makes optimal relay node selection jointly considering the channel state information (CSI) and the residual energy information of nodes to optimize the network lifetime. To minimize user and the whole network energy consumption, it uses the network outage probability as the optimization objective, and reasonable allocation of transmission power between the source node and the optimization relay node are done. Simulation results show that the proposed algorithm with lower complexity significantly improves the system´s channel capacity and energy efficiency.