基于随机Petri网的GSM-R越区切换成功率的形式化分析

Formal Analysis of GSM-R Handover Success Rate Based on the Stochastic Petri Net

首先建立了基于随机Petri网的GSM-R越区切换模型,在模型中综合考虑了信道故障、信道占用和越区切换参数配置不合理等影响越区切换成功率的因素。其次,说明了随机Petri网与马尔可夫链的关系,以及使用马尔可夫链分析"GSM-R越区切换的随机Petri网模型"的方法。最后,利用SPNP工具分析了影响GSM-R越区切换成功率的因素,发现GSM-R小区预留信道越多,越区切换成功率越高;列车运行速度越高,越区切换成功率越低;在一定范围内,列车追踪间隔越大,越区切换成功率就越高。

Firstly, GSM-R handover model is established based on the Stochastic Petri Net （SPN）. The factors which affect the handover success rate are considered in the model, such as channel fault, channel occupancy and unreasonable handover parameters. Secondly, this paper illustrates the relationship between the Stochastic Petri Net and Markov Chain （MC）, discussing the method of Markov Chain in analyzing the GSM-R handover model. Finally, the factors which affect the GSM-R handover success rate are analyzed with the SPNP tool. The result shows that the more GSM-R cell reserved channels are, the higher the handover success rate is. The result also shows that the higher the train speed is, the lower the handover success rate is. Within a certain range, the greater the train track interval is, the higher the handover success rate is.