The Research Of LTE System Handover Strategy

With the explosive growth of traffic data and popularization of intelligent equipments,the network capacity has achieved limitation.In order to satisfy the huge demand of traffic data,heterogeneous network and ultra dense network techniques are used as two efficient approaches.Through dense deployment of lower-power eNodeBs within the coverage of macrocell network,heterogeneous network and ultra dense network techniques could improve the throughput of user equipments and network significantly.However,the dense deployment will bring a series of problems,such as interference of neighbor cell,frequent handover and multiple handover failure.And those may be decrease the throughput of user equipments.Firstly,an efficient inter-frequency networking scheme is proposed to avoid the interference from neighbor cell.On this basis,three key parameters of A5 handover trigger conditions are studied on influence of handover performances.To control the influence of inter-parameters,the variable-controlling approach is used to analyze each parameter's influence on handover performances.Then,based on the optimal configuration of handover parameters,the problem of mobility management is studied,and speed-based handover strategy is proposed.Based on speeds of user equipments,forbidding high speed user equipments contecting to macrocells,and this handover strategy improves the throughput of user equipments within the coverage of microcells and the throughput of microcells.Finally,the load balancing problem on ultra dense network is investigated,and cell-throughput-based optimal handover strategy is suggested.Considering the throughput of each microcell and mobility trajectory of user equipments,the priority of each microcell index is used for the cell selection.Simulation results validate optimization effect of optimal handover strategy.