Mobility Management in Small Cell Networks

The cell sojourn time and the handoff rate are considered as the main parameters in the mobility management of the cellular systems. In this paper, we address the mobility management in a two-tier heterogeneous network (HetNet) and propose a framework to study the impact of different system parameters on the handoff rate and the small cell sojourn time. In the proposed framework, the overlapping coverage among the small cells and the number of overlaps on the path of a reference user equipment (UE) are derived to obtain the actual time that the reference UE spends in each small cell during its movement from the starting point to the destination point. The results show the accuracy of the analysis in this paper in comparison to the analysis when ignoring the impact of the overlaps. The results also show the importance of considering the overlaps among the small cells in dense HetNets.