User association in heterogeneous network with dual connectivity and constrained backhaul

摘要

A novel user association model for heterogeneous network (HetNet) with dual connectivity (DC) and constrained backhaul is proposed in this paper, where not only the best combination of serving macro cell and small cell for each user to associate is selected but also the optimal traffic split between the macro cell and small cell is determined to enhance both radio resource efficiency and backhaul capacity utilization. To solve this optimization problem, an intuitive algorithm based on iteratively solving two sub-problems is proposed. One sub-problem is a binary integer programming problem and a corresponding greedy algorithm is proposed, while the other sub-problem is a simple linear programming problem and can be easily solved. Numerical results show that the proposed model and algorithm can achieve better radio resource efficiency and backhaul capacity utilization compared with user association in HetNet without DC, which validate the capacity enhancement potentials of radio resource coordination in HetNet with DC.