Energy-Efficient Resource Allocation for Heterogeneous Wireless Network With Multi-Homed User Equipments

In this paper, we investigate the energy-efficient resource allocation problem for heterogeneous wireless network with multihomed user equipments. First, the energy-efficient resource allocation is formulated as an energy efficiency (EE) maximization problem, which is a mixed-integer nonlinear optimization (MINO) problem. We first introduce a continuity relaxation and Lagrange dual method to solve the MINO problem, which has relatively high computational complexity. For reducing the computational complexity of the resource allocation problem, we further propose a two-phase optimization method. Specifically, it includes the minimum rate guaranteed resource allocation and the energy-efficient resource allocation. Finally, we show that the two-phase optimization method achieves the suboptimal EE with significantly lower computational complexity compared with the optimal one. Simulation results show that the suboptimal algorithm achieves the EE performance higher than the conventional approach and comparable with the optimal one, but with much less complexity.