Energy-efficient power allocation for MIMO two-way cognitive relay networks

Energy-efficient design is becoming important in cognitive radio networks. In this paper, we investigate energy-efficient power allocation problem for multiple-input multiple-output (MIMO) two-way cognitive relay networks. The energy-efficient power allocation is formulated as a non convex optimization problem via maximizing the energy efficiency of the data transmission. The minimum required system data rate, the total power of two cognitive transceiver terminals and cognitive relay node (CRN), and the interference introduced to the PU are jointly considered. By introducing equivalent parametric convex optimization problem of the original problem, an iterative energy-efficient power allocation algorithm is proposed. Simulation results illustrate that the proposed iterative power allocation algorithm achieves higher energy efficiency than traditional capacity maximization method.