Base Station Assignment in Two-tier Dual Connectivity Heterogeneous Networks

The limited coverage of Small eNode Base Stations (SeNBs) in two-tier Heterogeneous Networks (HetNets) increases the control overhead and outage of mobile users. To overcome this challenge, two-tier Dual Connectivity (DC) HetNets is proposed. In such networks, each user can connect to two eNode Base Stations (eNBs) in different two-tier (a Macro eNBs (MeNB) in macro-tier and a SeNB in small-tier), simultaneously. In this paper, we investigate eNB assignment problem for maximizing the users' total data rate in the two-tier DC HetNets. Since the problem is a non-convex optimization problem, its computational complexity is high. To solve this problem, we transform it into a convex optimization problem. Then, an iterative algorithm is employed to obtain its optimal solution. The simulation results confirm that our proposed eNB assignment algorithm achieves the higher data rate as compared to the existing algorithm.