Adaptive double thresholds handover mechanism in small cell LTE-A network

Rapid demands for large capacity services and shortage spectrum resources have motivated the deployment of small cells in LTE-A network. Small cells are low-cost, low power nodes with limited coverage region, as the existence of small cells, more sophisticated network architecture increases the difficulty in dealing with mobility management. The contradiction between traffic demands and network resources is also very prominent, the rationally tradeoff between high quality service demands and signaling overhead in HO procedure should be considered in mobility management. Aiming at solving these issues, efficient handover (HO) mechanisms are more and more concerned to enhance mobility management in small cell networks. In this paper, we proposed a Self-Organizing Networks (SON) based Double Thresholds Optimization (DTO) handover algorithm, which offers an efficient method to mitigate handover signaling overhead while satisfying user´s requirements of service quality. Specifically, through optimizing two key HO parameters associated with HO procedure, DTO enhances mobility robustness management effectively. Furthermore, a system-level LTE simulator is implemented to evaluate the mobility performance. The results strongly verify that the proposed DTO algorithm can assist LTE network in achieving an appropriate compromise between handover (HO) signaling overhead and quality of service (QoS), besides, load balance is acquired with rational allocation of resources.