Abstract
This paper makes a formal analysis of the specification of a novel railway system, ATPB system, which is proposed by the authors. Firstly, on the basis of analyzing the requirements of the actual system, it established the specification of the ATPB system by VDM++. Secondly it proved the internal consistency which can guarantee there is no runtime error; and then it validated the satisfiability, which is used to make sure that the specification satisfies the requirement. At last, it simulated the system strictly according to the formal specification.
