SIGNAL+DRAHT | Issue 09/2002
CENELEC Approval of the Safe Transmission Unit for ETCS Level 2
With a view to the realisation of a communication-based train control and protection system, as presented by the ERTMS/ETCS systems, it is necessary to first actualise a reliable data exchange between mobile and stationary installations and (sub-)systems via open data networks. The systems that are communicating with one another usually themselves consist of further subsystems that communicate with one another via closed networks (bus systems). A safe transmission unit provides the interface between an open network and a local closed network in the case of radiobased train control systems, and serves as intermediary and as a separating device between these networks. This article describes the practical experience gained in the course of a CENELEC-conforming approval of a safe transmission unit for an ERTMS/ETCS Level 2 system from the point of view of the development phase.