相对于传统的基于通信的列车运行控制系统（Communicated Based Train Control, CBTC），下一代列控系统将具有架构可靠、速率快、成本低以及服务质量高等优点，且数据通信系统的可用性能够保障列车的安全和高效运行。本文面向下一代列控系统，首先设计了基于LTE-M（long term evolution-metro, LTE-M）的通信系统结构；其次针对下一代列控系统典型场景，利用确定与随机Petri网(Deterministic and Stochastic Petri Nets, DSPN)进行可用性建模，然后利用π-Tool进行模型求解和可用性评估。仿真结果显示，本文提出的基于LTE-M的下一代列控数据通信系统能够满足实际通信需求，其可用性分析方法可以完成数据通信系统的可用性建模与评估。

Compared with the traditional Communicated Based Train Control (CBTC), the next-generation train control system has the advantages of reliable architecture, fast speed, low cost, and high quality of service. Availability can guarantee the safe and efficient operation of trains. This paper is oriented to the next generation train control system. First, the structure of the communication system based on LTE-M is designed; secondly, for the typical scenarios of the next-generation train control system, use deterministic and stochastic Petri nets for availability modeling, and then use π-Tool for model solution and availability evaluation. The simulation results show that the next-generation train control data communication system based on LTE-M proposed in this paper can meet the actual communication needs, and its availability analysis method can complete the availability modeling and evaluation of the data communication system.