Reliability Analysis of Next-Generation CBTC Data Communication Systems

Communication-based train control (CBTC) systems are automated train control systems using wireless communications. The normal operation of CBTC systems depends on a reliable data communication system. The existing CBTC data communication system are based on train-to-ground communication, which suffers from too many subsystem interfaces and makes ground equipment extremely complicated. In next-generation CBTC systems, train-to-train communication is adopted with the advantages of higher efficiency and briefer system structure. Although train-to-train communication based CBTC systems has been implemented in urban rail systems. The data communication system reliability has not been studied before. In this paper, the next generation CBTC data communication system reliability is modeled with Deterministic and stochastic Petri nets (DSPNs). We design a next generation CBTC data communication system using LTE technologies, and set up laboratory test environment to test system performance. The performance data is converted as DSPN model parameters to evaluate system reliability. With the tested system performance measures, we evaluate the reliability of data communication scenarios, which includes the reconnection and handoff scenarios. Extensive simulation results are then given to illustrate the system reliability, which considers both the train to train communication link and train to ground communication link.