基于速度动态函的LTE-R越区切换优化算法

传统的LTE-R越区切换算法,采用固定切换迟滞门限和延迟触发时间的切换算法。但是当列车高速运行时,切换成功率明显下降,无法满足高速铁路无线通信系统对Qo S大于99.5%的要求。通过对切换流程、测量参数、控制参数的分析,提出一种基于速度动态函数的越区切换优化算法。该算法在低速、中速、高速3种列车运行状况下,更适宜高速铁路情景切换时机的选择。仿真结果表明:基于椭圆函数的LTE-R越区切换优化算法,既保证了列车在中高速运行时,越区切换成功率有着明显提升,又避免了列车在中低速运行时,乒乓切换事件频率过高。

LTE-R Cross-zone Handover Optimization Algorithm Based on Speed Dynamic Function

Traditional LTE-R cross-zone handover algorithm uses the algorithm with a fixed handover hysteretic threshold and delayed triggering time. But when the train runs at a high speed,the success rate of the handover decreases significantly and fails to meet the requirements of the high-speed railway wireless communication system,for which the Qo S must be more than 99. 5%. Based on the analysis of the handover process,the measuring parameters and the control parameters,this paper proposes a cross-zone handover optimization algorithm based on dynamic function of velocity. This algorithm with low,medium and high speed of three train running conditions is more suitable for the selection of handover time in high-speed railway scenario. Simulation results show that the cross-zone handover optimization algorithm based on elliptic function of LTE-R can not only ensure higher cross-zone handover success rate of the train running at medium and high speed,but also prevent frequent ping-pong switching event when the train runs at low and medium speed.