Dependability and Safety Analysis of ETCS Communication for ERTMS Level 3 Using Performance Statecharts and Analytic Estimation

Dependability and safety in European Rail Traffic Management System (ERTMS) level 3 are influenced by quality of localisation of trains and communication. In the paper, dependability and safety of European Train Control System (ETCS) communication for ERTMS level 3 is considered. In ERTMS level 3, traffic is controlled by so called moving block that is associated with the distance between subsequent trains. Relationship between probability of emergency train braking as a function of distance between subsequent trains is studied. In the study, the following parameters are taken into account: train speed, emergency braking distance, train length, position localization error, random variable of emergency braking and stopping times, parameters of transmission between trains and radio block centres, processing time in these centres. In order to find this relationship, the following methods: performance statecharts based and analytic estimation have been proposed. Quality of these methods is investigated.