Performance of handover in LTE heterogeneous network

Abstract

In this project, the performance for inbound and outbound handover between femtocell and macrocell in the LTE heterogeneous network was studied using simulation. To meet the surging traffic demand, it is proposed in the LTE standard to upgrade the traditional homogeneous cellular network to a heterogeneous architecture, where small cells such as femtocells and picocells are deployed in hot spots and covered by the macrocells. Unlike homogeneous networks, the inbound and outbound handovers of heterogeneous network have different requirements. It is one of the challenges of deploying heterogeneous networks because enhanced handover processes are required. In this project, the impact of handover margin (HM) values on the handover performance for user equipment with different speed was analysed in term of radio link failure (RLF) rate and ping-pong rate. Outbound and inbound handover were studied separately. The simulation results showed that larger HM values and higher speed led to higher RLF rate for outbound handover. In contract, for inbound handover, larger HM values and higher speed led to smaller ping-pong rate. The results suggest that the handover triggering for inbound and outbound handover should be selected separately to achieve an acceptable RLF rate and ping-pong rate for both handovers.