Pre-connect Handover Management for 5G Networks

Handover is an essential and significant component of mobility management in cellular networks. Handover management is more challenging in Fifth Generation (5G) networks because of ultra-reliable low latency communications (URLLC) requirements. This paper proposes a handover enhancement mechanism, namely pre-connect handover (PHO), for user equipment (UE) to support seamless and reliable handover management for 5G networks. PHO was designed for UEs to start the pre-connection process earlier than the 3GPP baseline handover to meet the strict low latency requirements, while satisfying the quality of service (QoS) demands. Specifically, the radio resources including a capacity-adjustable buffer are pre-allocated at the candidate target cell(s) in advance. The feasibility of PHO has been investigated by considering various scenarios and validated extensively via Network Simulator 3 (NS-3). The empirical results demonstrated that the proposed PHO can successfully achieve pre-connect handovers and support QoS without packet loss.