Energy efficiency optimization for MIMO cognitive radio network

Cognitive radio and MIMO have drawn significant attention to achieve high spectrum utilization efficiency. On the other hand, increasing energy demand and soaring energy related operating cost call for new design of energy efficient communication networks. In this paper, we study the energy efficiency optimization in a cognitive radio MIMO network. Specifically, we propose both distributed and centralized energy efficiency optimization algorithms. Since the original fractional problems are nonconvex, we use Dinkelbach´s method to transform them into parametric problem and solve the optimal solution iteratively. Simulation results show that, while the centralized algorithm outperforms the distributed algorithm in terms of network-wise energy efficiency, it may lose fairness among all CR links in high interference scenario.