04 May 2020

How UNISIG experts have contributed to the ERTMS/ETCS evolution

In 2018/2019, UNISIG continued to focus its activities on the maintenance of the ERTMS specifications, including the associated Baseline Compatibility Assessment (BCA). Under the leadership of ERA within the EECT (ERA Extended Core Team), UNISIG and the ERTMS Users Group kept carrying out the analysis and assessment of a set of Change Requests (CRs), considered to be addressed as a matter of priority to reach the interoperability target. From June 2018 to September 2019, this activity was the only one tasked to the EECT, waiting for the inputs from S2R related to the game changers. The set of CRs processed by the EECT will form the second ERA opinion correcting the ERTMS specifications.

To complement this work, all UNISIG suppliers communicated to ERA the specific behaviours of their on-board units to evaluate in the field the possible changes to be implemented by the IMs, with the target to allow all compliant on-boards to run on compliant infrastructures.

UNISIG suppliers proposed also a process to handle possible interoperability issues encountered within project execution, which has been endorsed by the Stakeholders Platform members and shared with ERA and DG MOVE.

UNISIG contribution to the ERTMS/ETCS evolution. Dedicated UNISIG workgroups (ATO, System Group, Euroradio and Cybersecurity) have been working in coordination with Shift2Rail to the preparation of technical inputs for the evolution of the ERTMS system, mainly in the field of ATO, future communication system (FRMCS) and ERTMS Level 3.

In 2018/19, the ATO draft specifications were frozen to be used for the S2R prototype testing campaign. The feedback from those tests have been submitted to the EECT to finalise the ATO specifications.
End of 2018, the UNISIG System Group started to analyse the impact of the future radio system (FRMCS) on the on-board architecture, where migration from the current system is a key subject. This activity is undertaken in collaboration with EUG, UIC and UNITEL a UNIFE’s dedicated Committee.

UNISIG is also active in all ERA coordination groups dealing with the ERTMS game changers, in particular the future communication system and the one coordinating the Command Control System Architecture (ERA CCS-A) aiming at defining the scope of the next version of the CCS TSI (targeted in 2022/23).

UNISIG representatives participated to coordination meetings organized by ERA on the evolution of the radio communication system for railways. Those meetings organised on a quarterly basis are chaired by ERA to coordinate and plan the activities from the various stakeholders (UIC, UNITEL companies, S2R, UNISIG, ERA, IMs, EUG) involved in the FRMCS development.

Testing, Certification and Authorisation remains a crucial topic for ERTMS. All stakeholders recognise that, on top of constituents testing, compatibility testing between on-board equipment and real trackside configurations is mandatory.

The Test & Validation sub-group of the ERTMS Stakeholders Platform, chaired by UNISIG and made up of representative bodies’ experts, developed a generic process endorsed by ERA. This ESC (ETCS System Compatibility) process has been included in the updated version of the CCS TSI adopted by RISC in January 2019.

The UNISIG Certification and Authorisation working group was very active in contributing to this updated version. UNISIG introduced also a process to avoid re-authorisation in case of minor modifications, also introduced in the last version of the CCS TSI.

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