In the European ETCS Level 2 rail system, train movements are supervised by control centers known as RBCs (Radio Block Centre). Each RBC manages a section of the line rail and communicates directly with trains via radio to transmit movement authorizations. When a train moves from one section to another — for example, between two control centers or between two countries — it must switch to a different RBC.
Problem: the current standard requires the two RBCs to communicate directly with each other to organize the train’s handover, which makes the system complex, especially if they are supplied by different companies. This is why the EBA (Eisenbahn-Bundesamt) is exploring an alternative approach: carrying out the RBC changeover without a direct connection between the two RBCs.
To study and validate this approach, the EBA is using the ETCS simulator developed by CLEARSY. This simulation environment enables the entire ETCS railway system to be represented within a single software package: signalling (interlocking), RBCs, on-board train equipment (OBUs), driver interface (DMI) and radio network.
This capability was crucial to the project, as it enables the realistic reproduction of a boundary situation between two RBC zones. It is thus possible to:
- simulate a complete boundary line, with realistic parameters (speed profile, gradients, balises, telegrams);
- configure two RBCs, one yielding and the other accepting;
- test complex operational scenarios, such as Full Supervision or On Sight mode, as well as degraded situations (system incompatibilities, faulty beacons, single EDOR communication module);
- verify operational continuity when switching from one RBC to another, without a direct interface between them.
Beyond the functional demonstration, the simulation also enables detailed analysis of braking curves, supervision transitions and radio constraints, currently using GSM-R and in future with FRMCS. This ensures the design is safe before any revenue service.
With this independent, multi-vendor environment focused on system validation, CLEARSY provides an essential tool for experimenting with and evaluating new approaches to ETCS operations, and for contributing to the development of truly interoperable solutions on a European scale.
The ultimate aim is to enable the ERA (European Union Agency for Railways) to evaluate this approach.
You can find out more by reading the article: Developing an RBC changeover (without an RBC / RBC coupling)