Study on feasibility of SATCOM for railway communication

Final Report
2. INTRODUCTION
2.1 DOCUMENT PURPOSE
With the purpose of studying the feasibility of Satcom solutions for the signalling (critical) applications
of the railway domain, the European Union Agency for Railways commissioned Indra Sistemas and
ALG to conduct the project ERA 2016 01 SC, ―<strong>Study</strong> on feasibility of SATCOM for railway
communication‖.
This document is the Final Report, which aims to describe the work performed between June 2016
and January 2017.
The European Union Agency for Railways will hereafter be referred to as ―the Agency‖.
2.2 CONTEXT OF THE STUDY
Communications for safety-critical railway applications have become an essential area within the
railway domain, given that, under the current legal framework, new trains operate under the
supervision of an Automatic Train Protection System (ETCS). These systems are critical since they
provide movement authorizations and are able to stop the train by applying brakes when required (to
avoid exceeding the speed limit).
GSM-R (Global System for Mobile Communications – Railway) is the current communication
technology used in railways and is used as communication support for: safety-critical applications,
such as data transmission between train and Radio Block Centre (RBC) for ETCS Level 2; and voice
communication, such as driver transmissions, maintenance and shunting personnel, etc.
Although the use of GSM-R for new services and applications is limited due to its reduced bandwidth
and the absence of high-capacity-demanding applications, the technology will have to be replaced in
the future mainly motivated by GSM-R‘s obsolescence, which is expected around 2030, rather than
changes in functional and/or performance requirements.
Wireless technology is continuously evolving and the need to replace GSM-R can be regarded as an
opportunity to increase (if possible) the number of applications supported —not only safety-critical
applications, but also mission-critical and even those for maintenance or passenger entertainment.
This opportunity can also be useful for separating railway safety application requirements from the
communication system, to ensure that future changes to the communication system are made
smoothly.
In this situation, several technologies have been postulated as a GSM-R substitute in the railway
domain. Within the first phase of this migration process, several land-base and also SATCOM
technologies are being studied.
Given that GSM-R is part of ERTMS, it seems unlikely that any current communication system
(satellite or terrestrial) could be able to support railway voice and data applications without having to
modify and upgrade the on-board equipment. The SATCOM system analysis to be performed is
intended to yield indications on whether some of the current (or even future) solutions, with
modifications, might be able to provide and support the railway requirements for voice and data used
in the rail operation.
Doc.Nº: SRAIL-FNR-010-IND
Edit./Rev.: 1/1
Date: 16/02/2017
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