Page 116 - 360.revista de Alta Velocidad - Nº 5

Fernández Suárez, Enrique. Rodríguez, Antonio.

The full picture about compatibility is:

As a summary, Baseline 3:

• offers backward compatibility for baseline 3 trains on baseline 2 infrastructure.
• offers the possibility to upgrade a baseline 2 trackside while keeping most of the existing
balises untouched.

• offers the possibility for additional trackside functionalities without losing compatibility
with baseline 2 on boards (additional baseline 3 information will be ignored by a baseline 2
train but taken into account by a baseline 3 train)

A detailed document has been released by the European Railway Agency (ERA) together with
the Infrastructure Managers and Trains Operators, to identify all the potential interoperability
problems between Baseline 2 and 3 subsystems, called Baseline Compatibility Assessment.

The document about Baseline 3 MR1 compatibility can be found in:
http://www.era.europa.eu/Document-Register/Pages/Baseline-Compatibility-Assess-
ment-B3-MR1.aspx
The conclusion, for the evolution from version 2.3.0 D to Baseline 3 MR1, is “vast majority
of the 436 analysed Change Requests, the analysis demonstrated that the compatibility
objectives for Baseline 3 […]have been achieved and no potential compatibility problems
were identified”.
Besides, “some other potential compatibility issues were identified, due to shortcomings or
‘grey areas’ in Baseline 2, for which mitigation measures could be needed to ensure
interoperability.”
*(extracts from Baseline Compatibility Assessment - Final Report, Reference EUG_UNISIG_BCA, version
1.0.0)
This document about Baseline 3 R2 compatibility can be found in:

http://www.era.europa.eu/Document-Register/Pages/Baseline-Compatibility-Assess-
ment-for-B3-R2.aspx

The conclusion is for 50 out of the 55 CRs added in MR2, the compatibility between the baseli-
nes has been achieved and no potential compatibility problems were identified. For other 5 CRs
(CR 933, 1089, 1184, 1249 and 1262) have been identified mitigation measures.

All these analysis have been performed to facilitate migrations to Baseline 3, and coexistence
of both Baselines from a legal but also real point of view.

And together with specifications evolution, the products also evolve.

New generation of ERTMS onboard equipments have:
- reduced HW, with less components and less power consumption

- more functions integrated in the European Vital Computer
- more processing capacities
- and open to other standards /equipments used in other sectors.

114 360.revista de alta velocidad