Community Research and Development Information Service - CORDIS


ERSAT EAV Report Summary

Project ID: 640747

Periodic Reporting for period 1 - ERSAT EAV (ERTMS on SATELLITE – Enabling Application Validation)

Reporting period: 2015-02-01 to 2016-01-31

Summary of the context and overall objectives of the project

The Horizon 2020 funded ERSAT EAV project aims to verify the suitability of EGNSS services as EGNOS and Galileo for the railway sector – and in particular within the regional lines. The project is defining and developing the safe localisation of train positioning based on satellite technology and ensuring such a system is in harmony with the European ERTMS standard.
The main general objectives of ERSAT EAV are the following:
• To improve the sustainability and growth of the regional and local railway lines, guaranteeing the safety:
• minimizing the costs for railway signalling infrastructure, without sacrificing safety;
• safeguarding the European efforts for standardization of signalling systems (ERTMS);
• promoting the adoption of GNSS technology into the ERTMS for improving the competitiveness of European railway industry.
• The utilization of EGNOS and Galileo Services, as foreseen in the ERTMS MoU signed in 2012 by the railway stake-holders:
• Exploiting and adapting the enabling GNSS key technologies;
• Complementing the existing GNSS technology and operational services for railway application, fulfilling user requirements (i.e. SIL-4).

In order to reach such goals, the ERSAT EAV project activity is structured according to the following steps:
• starting from the definition of the railway requirements and scenarios, in particular:
• involving the Railway Stakeholders (Users and Industries) in requirement identification and harmonization;
• creating liaisons with other related projects (3INSAT, NGTC, S2R, GRAIL2, SATLOC …);
• verifying the suitability of EGNSS (including EGNOS and Galileo early services) for safety railway application, focusing in particular on the regional lines’ scenario;
• Conducting a measurement campaign, in real operating conditions, and analyzing the results, in order to evaluate the gaps to be filled, in terms of technological criticalities and in relation to the current railway requirements;
• Defining the system solution, in terms of system architecture and related specifications, for the safe localization of the trains, based on satellite technologies harmonized to the European ERTMS standard;
• Analyzing the impact in terms of cost/benefit and sustainability;
• Developing the solution in two phases:
• 1st Phase: Modelling and Simulation, in the DLR certified lab (RailSite) and using a DLR mobile lab for in field measurement & testing (RailDrive);
• 2nd Phase: by implementing the innovative SAT-based solution on the Trial Site made available by RFI & Trenitalia, and part of the Sardinian regional line (Cagliari-San Gavino).
• Testing and validating the solution that will become a reference to be considered in future standardization and certification initiatives;
• Disseminating and exploiting the ERSAT EAV results, involving railways and satellite communities, contributing to the standardization process of the ERTMS platform with GNSS.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

All the project activities have been carried out according to the work program that has been revised at the end of 2015 (Gantt chart v.02) and agreed with GSA Project Officer as well as with the project reviewers. Basically this latest version of the project planning extended the time duration of almost all the work packages, while ensuring the final project deadlines, in order to allow time to collect, consolidate and harmonize all the project requirements and deriving from them all the inputs needed for the safety analysis, the system and sub-system architectures definition, the measurement campaign requirements, as well as and the cost/benefit analysis.

In the early stage of the project, all the requirements to be considered in ERSAT EAV have been identified and defined by the WP2 (ERSAT EAV REQUIREMENTS). In particular part of such requirements come directly from the users, the railway operators and their Association, some of them involved as project partners (i.e. ASSTRA, DB Netz, RFI and Trenitalia), and the remaining part deriving form a strategic liaisons with other relevant initiatives (past and the near future), concerning satellite technologies in the railway sector: i.e. 3INSAT, NGTC, S2R, GRAIL2, SATLOC ...
The user’s needs considered:
• The European market evolution that is setting new priorities on the ERTMS technology roadmap (see the ERTMS MoU signed in 2012 by the railway stake-holders, that envisaged both GNSS localization and IP TLC as new technologies to be introduced in the ERTMS standard);
• Some international markets, where the adoption of the new satellite assets is taking place at a much higher speed than in Europe: i.e. in Australia, USA and Russia
Bearing in mind that the scope is the definition of a standard solution that can be customized on each country, WP2 addressed the following issues:
• Definition of requirements apportionment strategy,
• subdividing the requirements in: safety and interoperability standard, localization and augmentation system, TLC system, ERTMS/ETCS signalling system, operational rules;
• Identification of reference scenarios and related specific requirements, selecting in particular German and Italian regional railway lines, including among them the Sardinia Trial Site line.
• Harmonization of user requirements, according to the above apportionment strategy, and proposal of a standard solution for the satellite-based technology signalling system;
On the basis of these harmonized requirements, the WP3 performed a GNSS Measurement Campaign in a real railway scenario, namely the Sardinia Trial Site:
• Collecting raw data from COTS GNSS receivers both on the equipped running train as on the wayside locations where the Reference Stations of the Ansaldo STS proprietary Augmentation network, have been placed;
• Constructing the ground truth as reference for the measurements
• Post-processing the collected data.
• Identifying the GNSS signal blocking sources and their effect on ERTMS
All such data have been collected and stored in an ad-hoc built database containing all the real recorded signals from GPS, Galileo, GLONASS and EGNOS satellites in order:
• To assess the current achievable performance in real scenarios
• To compare candidate GNSS configurations and algorithms
• To create GNSS performance baseline scenarios.
Additionally, a complementary measuring data campaign has allowed analysing GNSS blocking sources and EMI on the ERSAT pilot line. Likewise, this data campaign has supported the main GNSS measuring campaign with preliminary results with EGNOS performance.

In parallel to the WP3 activities, the WP4 (REFERENCE ARCHITECTURE DESIGN & PERMORMANCE ANALYSIS) performed a preliminary Safety and Hazard Analysis, aimed to identify hazards related to GNSS LDS ensured essentially by both EGNOS and a Local Augmentation Network. This analysis got started by a joint working group activity that involved both the nominal participant

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Remarkable progresses are distributed throughout the entire project life cycle. Since the requirements, drawing on different markets and national peculiarity, as well as different scenarios, that achieved a high level of synthesis and harmonization not common at the time with other similar projects. This was possible thanks to the presence of many railway infrastructure managers, operators and their Association, like ASSTRA, DB Netz, RFI and Trenitalia.
On this basis, another relevant outcome is represented by the GNSS measuring campaign, that collected data from the available GNSS constellations and EGNOS operational satellites, assessing the achievable level of performance of the GNSS service in the real railway environment, namely in the Sardinia trial site. The completeness of these data, required for this evaluation, came out from the measurement configuration, adopting not only static but also dynamic tests that have been performed on board to an operational train along a Regional railway line. In addition to raw GNSS data collection in RINEX format, also GNSS samples have been recorded at IF level, as well as the interference monitoring and GNSS signal characterization have been performed.
Since the application of GNSS, and in particular EGNSS, in Railway Signalling is very innovative, the knowledge transfer and adaptation processes, from the aviation environment to the railway one are very complex. For this reason, ERSAT EAV got started by jointly involving not only ESSP experts in EGNSS, and their safety and certification branches but also ASTS, as expert from the Railway Signalling domain and its Safety related aspects. The goal was taking into account from the early stages of the project both: the specific requirements and characteristic belonging to ERTMS domain, as well as identifying and considering all the specific hazards and their possible mitigations. Following this approach, ERSAT EAV completed a first preliminary safety analysis while further harmonization activities are already planned to contextualize the hazards and the performances of a GNSS receiver in the railways environments and together with the on board ERTMS constituents.
Concerning the ERSAT EAV solution, it is worth to mention that the adopted strategy in system design, consisting in the best approach for minimizing the impact on the ERTMS ecosystem, maintains full compatibility with the current legacy ERTMS Level 2 solutions.
In the present situation, the train location determination in ERTMS/ETCS level 2 is mainly based on physical balises that are a kind of transponder installed on the track at geo-referenced locations. When the train passes on a physical balise, its on-board Balise Transmission Module (BTM) is able to detect this event, extracting the specific message (telegram) contained in that physical balise. At this point, the BTM applies a time and odometer stamp to the received message- that contains among others a unique balise identifier and delivers it to the Radio Block Center (RBC) via a train-to-track mobile network (e.g. GSM-R), using means of a safety protocol. Then the RBC processes the reported information and sends back to the train the so-called Movement Authority (MA) containing the permission for the train to move to a specific location with speed supervision.
Therefore, in present ERTMS L2, the train position and speed are computed on board by the odometer, which relies on the balises deployed along the track, as reference points, to periodically reset the accumulated errors. In particular, the balises determine the train absolute position and the odometer estimates the relative distance from the Last Relevant Balise Group (LRBG).
To speed up the integration of GNSS technology into ERTMS/ETCS, minimizing its impact, the concept of “Virtual” Balise has been introduced in ERSAT EAV. In essence, the GNSS based Virtual Balise Reader estimates the instant at which the train will pass over the location where the nex

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Record Number: 186644 / Last updated on: 2016-07-14