Formal verification of Communication based Train Control system

In the CBTC (Communication-based Train Control) system, the wireless terminals (repeaters) are the communication bridges between the control-center and the on-board system. This paper presents a formal analysis of the train-to-ground communication link verification (TCLV) system. Firstly, this paper lists the requirements and analyzes the necessary system state and operations, then transforms the natural language describing system into a rigorous mathematical described model. At last, for the formal model, the proof obligations are proved to verify its internal consistency, and the validations are proved to verify the states and operations satisfying the expected requirements. The result of proof denotes that the actual system designed as the specification described in this paper would satisfy the requirements under the premise of safety and reliability.