Theoretical analysis of handover failure rate in heterogenous networks under random shadowed model

Heterogenous networks (HetNets) consisting of both macrocells and small cells are capable of improving system capacity and user throughput significantly. However, the deployment of various small cells may result in frequent handover between the macrocell and small cells, and between small cells, and the possible handover failure (HoF) may severely affect system performance and user quality of service (QoS) guarantee. In this paper, we consider a HetNet consisting of one macroe NodeB (MeNB) and one picoe NodeB (PeNB), the user equipment (UE) moves along the coverage area of the two eNodeBs. The probability of HoF of the UE is examined under the shadowed fading channel model and the analytical expression of the probability of HoF is derived as a function of user velocity, the threshold of reference signal receiving power (RSRP), the duration of time-to-trigger (TTT) timer and the characteristics of the random shadowing effects.