Energy-efficient component carrier configuration and power control for carrier aggregated systems

The energy efficiency (EE) optimization in downlink carrier aggregated networks is addressed in this paper. To maximize EE by joint component carrier (CC) configuration and power control, we first model the problem as a mixed integer non-linear programming problem, which is NP-hard. Then the existence of optimal solution is proved. Based on the properties of optimal solution obtained by analysis, an optimal algorithm is found. Finally, a low-complex suboptimal algorithm is proposed by exploiting inherent features of CC configuration and dividing power control into two subproblems, which can be solved optimally. Simulation results show that EE of proposed algorithms is significantly better than that of conventional algorithm, and the suboptimal algorithm can greatly reduce complexity with little loss of EE in comparison to the optimal algorithm.