GSM-R (Global System for Mobile Communications – Railway), the radio communication system mainly used for the implementation of the ERTMS.It is specified in both the TSI CCS and EIRENE (abbreviations below).

Is it possible to use other radio communication systems than GSM-R for ERTMS? 


ERTMS Communication
ERTMS Communication 
Photo Credit: Comtest Wireless



Previous and ongoing experiences around the world show that it is possible to use other radio communication systems like TETRA (Terrestrial Trunked Radio) and LTE (Long-Term Evolution) with ETCS if they can fulfil the above-mentioned specifications. 


Australia (TETRA)

Siemens Mobility and DAMM worked in an ERTMS/ETCS Level 2 project in Australia. For this project, they used TETRA Packet Data with ETCS to ensure communications between subsystems [1].

To approve this solution, after its implementation, they tested it according to specifications that specify the worst-case conditions for ETCS communication. Tests were approved.


Kazakhstan (TETRA)

Using the same radio communication system as the previous example (TETRA), Bombardier Transportation (recently acquired by Alstom) and Teltronic carried out together an implementation of the ERTMS using other radio communication system than GSM-R for the company Kazakhstan Temir Zholy (KTZ), the rail operator for passenger and freight [2].

Tests showed a stable function according to the requirements and specifications. 

The project is a 300-km-line and the solution was recognized by KTZ.


India (LTE)

In January 2021, Alstom announced the winning of a Signalling & Telecom system contract in India. The particularity of this contract is that a solution for a communication system based on LTE will be deployed. Furthermore, this project represents the first Indian line that will use ERTMS/ETCS L3 Hybrid.  


Abbreviations:

ERTMS: European Rail Traffic Management System

TSI CCS: Technical Specifications for Interoperability Control Command & Signalling

EIRENE: European Integrated Radio Enhanced NEtwork


Sources:

[1] https://tcca.info/siemens-and-damm-complete-testing-of-etcs-over-tetra-packet-data/

[2] https://www.teltronic.es/en/teltronics-tetra-solution-certified-to-support-etcs/

[3] https://www.alstom.com/press-releases-news/2021/1/alstom-wins-major-signalling-telecommunication-systems-contract-rapid