An Adaptive Handover Trigger Strategy for 5G C/U Plane Split Heterogeneous Network

Fifth-generation (5G) control/user (C/U) plane split heterogeneous network may cause more serious handover problems than traditional networks, especially for the inter-macrocell handover. In addition, the mobility behavior of mobile node (MN) may also result in improper handover triggers. In this paper, an adaptive handover trigger strategy (AHTS) is proposed to predict the received signal strength indicator (RSSI), to guarantee that handover trigger is accurate and timely when the MN is moving. First, the fast dynamic time warping (FastDTW) algorithm as well as the density-based spatial clustering of applications with noise (DBSCAN) algorithm are used for clustering trajectories to discover the mobility patterns of MN. Then multiple hidden markov models (HMM) are trained based on the results of clustering. Finally, according to the HMM model which is selected based on the similarity between test trajectory and each cluster center, an adaptive RSSI predication (ARP) algorithm is implemented to predict the values of the RSSI. Simulation results show that our strategy outperforms the existing schemes in terms of the handover probability and the handover success probability.