Search

Railway applications are in continuous evolution with the aim of offering a more efficient, sustainable, and safer transportation system for the users. Generally, these applications are constantly exchanging information between the systems onboard the train and the trackside through a wireless communication. Nowadays, Global System for Mobile communications-Railway (GSM-R) is the technology used by European Train Control System (ETCS), but it is becoming obsolete. Therefore, alternatives for this technology have to be found for the different railway applications. Its natural evolution is to move forward with the latest technology deployed: Long-Term Evolution (LTE), which the Public Land Mobile Networks (PLMN) have already deployed. Therefore, testing the performance of this communication technology in the railway environment could be useful to assess its suitability and reduce the cost of railway network dedicated deployment. In order to do that, a methodology to characterize the communication environment is proposed. The main goal is to measure geolocated impairments of any communication channel in a railway environment being able to determine its behavior of the different communication technologies and find out possible coverage issues. Moreover, it could help in the selection of suitable communication technology for railway. This paper presents a brief description of the communication for railways and its QoS parameters for performance measuring. Afterward, the testing methodology is described, and then, the communication channel measurement campaign on a real track in Spain where the railway environment is variable is presented (tunnels, rural/urban area…). Finally, the measurements and results on this real track in Spain are shown. The results provide suitability of the 4G technologies based on the delay requirements for the implementation of ETCS over it.

Even though satellite-based positioning increases rescue workers’ safety and efficiency, signal availability, reliability, and accuracy are often poor during fire operations, due to terrain formation, natural and structural obstacles or even the conditions of the operation. In central Europe, the stakeholders report a strong necessity to complement the location for mixed indoor-outdoor and GNSS blocked scenarios. As such, location information often needs to be augmented. For that, European Global Navigation Satellite System Galileo could help by improving the availability of the satellites with different features. Moreover, a multi-sensored collaborative system could also take advantage of the rescue personnel who are already involved in firefighting and complement the input data for positioning. The Autonomous Indoor & Outdoor Safety Tracking System (AIOSAT) is a multinational project founded through the Horizon 2020 program, with seven partners from Spain, Netherlands and Belgium. It is reaching the first year of progress (out of 3) and the overarching objective of AIOSAT system is to advance beyond the state of the art in tracking rescue workers by creating a high availability and high integrity team positioning and tracking system. On the system level approach, this goal is achieved by fusing the GNSS, EDAS/EGNOS, pedestrian dead reckoning and ultra-wide band ranging information, possibly augmented with map data. The system should be able to work both inside buildings and rural areas, which are the test cases defined by the final users involved in the consortium and the advisory board panel of the project

Independently on the business case addressed, one of the main drawbacks of the railway use cases that need continuous Global Navigation Satellite Systems data is the lack of availability for the 100% of the time of the journey. Additionally, the integrity assessment of the position estimation given is also mandatory for safety critical applications. Thus, tunnels and multipath effects are one of the most challenging situations for the continuous positioning systems. In this context, an autonomous on-board Complementary Positioning System has been proposed to overcome the limitation of Global Navigation Satellite System based positioning systems. This paper proposes a positioning enhancement solution by means of fusing data from the satellite navigation system and inertial measurement units. That hybrid solution provides higher availability and accuracy to the positioning specially on known blocked scenarios, such as tunnels, or urban canyons, by means of a novel environment aware map aided software technique named Known Blocked Scenarios algorithm… This paper describes the Complementary Positioning System and the field test carried out in a challenging environment to validate the enhancement proposed by the authors, which demonstrate the benefits that this system has in known harsh environments for railways.

Railway infrastructure and vehicle maintenance expenditures are estimated to cost over 20,000M€ per year at European level. This indicates the demand for developing a low-cost system capable of providing prognostic information about the health status of the railway at the points of the interaction between the vehicle and the infrastructure (wheelset, pantograph, rail and catenary). To achieve these capabilities, SIA (System for vehicle-infrastructure Interaction Assets health status monitoring) is being developed by a consortium from five different European countries. Within the SIA system, events are captured by a network of sensors, which are time stamped and then accurately geo-referenced by the positioning sub-system of SIA. The positioning sub-system is based on EGNSS positioning algorithms tailored for the railway environment and comprises onboard as well as back-office processing. GNSS-based positioning in the railway environment is very challenging. Hence, Galileo with its advanced signal structure is utilized in SIA (in addition to GPS) to improve availability as well as accuracy. The onboard positioning algorithm has been developed based on a novel GNSS-IMU hybridized approach. The new approach can overcome frequent measurement gaps within the GNSS observations and maintain the accuracy level required by SIA system. An overview of the back-office positioning in SIA complements the presentation of the onboard processing.

Nowadays, the wireless networks have an important role in the deployment of several means of transports, platforms and applications. In the particular case of roads and vehicle area, some ideas are starting gaining importance such as the autonomous vehicle. In order to reach this ambitious goal, the wireless networks are a strategic issue for the communication between vehicles (V2V) and between infrastructure and vehicles (V2I), generally known as vehicle-to-everything (V2X). In this current moment, the most deployed cellular network is LTE (Long Term Evolution), progressing to 5G technology. Because of this, this paper shows the measurement of the LTE technology and the phenomena that affects this technology at IP level. To reach this last goal, the on-site testing of a measurement system is needed allowing to quantify network impairments of a communication channel in a given road environment. In this paper, the system capable of measuring a communication channel is explained and it is shown how an on-site testing of the communication channel of a specific road has been measured in terms of the RTT network impairment. As well, the results of the measurement has been analysed and explained. Finally, some conclusions are presented.

The European Union (EU) is bolstering the railway sector with the aim of making it a direct competitor of the aviation sector. For that to occur, railway efficiency has to be improved by means of increasing capacity and reducing operational expenditure. Tracks are currently used below their maximum capacity. Given this fact and the EU’s goals for the railway sector, research on solutions for on-board positioning system based on global navigation satellite systems (GNSS) have arisen in recent years. By taking advantage of GNSS, safety critical positioning systems will be able to use the infrastructure more efficiently. However, GNSS based positioning systems still cannot fulfill current normative validation processes, mainly, due to the fact that GNSS based positioning performance evaluation is not compatible with the key performance indicators (KPIs) used to assess railway systems performance: reliability, availability, maintainability, and safety. This paper proposes a methodology and unified key performance indicators (KPIs). Additionally, it shows real examples to address this issue. It aims to fill the gap between the current railway standardization process and any on-board positioning system.

Global Navigation Satellite System (GNSS) has become the main technology in terms of navigation technologies, as it ensures a worldwide absolute outdoor positioning. The transportation sector employs this technology to obtain a position, velocity and time solution for the corresponding outdoor application. When talking about indoor positioning, nevertheless, GNSS becomes an unreliable navigation technology, as the below-noise signals get obstructed. In these cases, the Ultra-Wideband (UWB) technology can be used as a navigation solution, as its anchor trilateration based radiofrequency positioning resembles GNSS’s principle and, depending on the anchor location, it can be used for indoor positioning. However, just like other radiofrequency based technologies, UWB is vulnerable to interferences and the multipath effect. With the aim of overcoming these drawbacks, this article discusses how to apply Fault Detection and Exclusion (FDE) techniques to avoid using faulty anchors when employing UWB in indoor/urban environments such as tunnels or train stations.

The popular Internet service, YouTube, has adopted by default the HyperText Markup Language version 5 (HTML5). With this adoption, YouTube has moved to Dynamic Adaptive Streaming over HTTP (DASH) as Adaptive BitRate (ABR) video streaming technology. Furthermore, rate adaptation in DASH is solely receiver-driven. This issue motivates this work to make a deep analysis of YouTube’s particular DASH implementation. Firstly, this article provides a state of the art about DASH and adaptive streaming technology, and also YouTube traffic characterization related work. Secondly, this paper describes a new methodology and test-bed for YouTube’s DASH implementation traffic characterization and performance measurement. This methodology and test-bed do not make use of proxies and, moreover, they are able to cope with YouTube traffic redirections. Finally, a set of experimental results are provided, involving a dataset of 310 YouTube’s videos. The depicted results show a YouTube’s traffic pattern characterization and a discussion about allowed download bandwidth, YouTube’s consumed bitrate and quality of the video. Moreover, the obtained results are cross-validated with the analysis of HTTP requests performed by YouTube’s video player. The outcomes of this article are applicable in the field of Quality of Service (QoS) and Quality of Experience (QoE) management. This is valuable information for Internet Service Providers (ISPs), because QoS management based on assured download bandwidth can be used in order to provide a target end-user’s QoE when YouTube service is being consumed.

The suitability of EGNSS (including EGNOS and Galileo early services) for safety railway applications has been analysed by several European projects such as Grail, Grail-2, Satloc, 3InSat, and it is currently being analysed by ERSAT EAV. ERSAT EAV in particular is addressing the following three challenges beyond the state-of-the-art: a) reuse of ETCS odometry by adding the virtual balise concept to eliminate the fixed balise along the line; b) adoption of the public EGNOS Augmentation network “upgraded” with Local augmentation networks to fulfil the railways’ requirements; c) verification and validation of alternative GNSS solutions to guarantee localization functions in areas where the GNSS signal is not available and/or subject to interference. This paper focuses on the third of these challenges, addressing the design and the implementation of a complementary positioning system (CPS) for GNSS-denied areas. This system is based mainly on the Public Land Mobile Network (PLMN) information but also incorporates additional source information (such as predefined GNSS blocked zone information and GNSS positioning information for calibration purposes, when available) in order to enhance positioning performance. This paper deals with the different steps taken to create the CPS: 1. Analysis of the alternatives for complementary positioning systems when GNSS is not available 2. Simulation and development of algorithms for the CPS in the lab 3. Creation of a prototype for the CPS based on COTS components More specifically, after analysing the state-of-the-art technologies, the algorithms for the selected solution will be implemented in the laboratory. In order to analyse the theoretical performance of the algorithms, the environment and observables for the algorithms will also be modelled in the simulation platform. The performance of the CPS will be analysed in terms of accuracy, reliability, continuity and integrity in a way similar to the GNSS systems. Finally, the algorithms will be implemented in a prototype based on COTS components so that the CPS will not be a theoretical solution but also a real solution that could be useful for the on-board positioning function in trains when GNSS solutions are not available.

This paper presents the implementation of an Angle of Arrival (AoA) estimation algorithm using Field-Programmable Gate Array (FPGA) technology as a part of a Smart Train Positioning System (STPS). The STPS takes advantage of the combination of different technologies and techniques, such as Global Navigation Satellite System (GNSS) and the AoA of the Global System for Mobile Communications-Railway (GSM-R) signals, to determine the real time train position. Furthermore, a complete software AoA system simulator has been implemented and used to validate the implementation of the AoA algorithm in the FPGA.

Global System for Mobile Communications – Railway (GSM-R) is one of the most used radio technologies in railway network for transmitting control information. However, nowadays IP-based technology is quite up-to-date and mature. Since there are many approaches for providing support to IP mobility and adaptable communications, it is important first to measure and understand the performance of IP networks in current railway routes. This paper provides the details of a framework entitled Channel Characterization Tool (CCT), a distributed network performance evaluation framework for the feasibility study of public IP networks in railway network. This paper describes the architecture of CCT, and some results obtained in field testing, as the first step in the validation of the framework. Finally, future research lines and conclusions are drawn.

In order to identify the different external impairments that could exist in the railway environment. A survey of these effects is presented with the aim of identifying the different phenomena that could affect to the communication channel. On one hand, common effects linked to the signal transmission over a wireless communication channel are analysed. On the other hand, as GSM-R is the current communication technology employed in ERTMS, the disturbances interfering it have been studied. Finally, some solutions to mitigate these effects are listed, in this case, focused in handover solutions.

The current low modal share of intra-EU rail freight transport is partly due to limitations of operational and technical nature, which impact the overall capacity and performance of the sector. In order to overcome these issues, Shift2Rail set a specific Innovation Programme 5 (IP5) focused on Technologies for Sustainable & Attractive European Rail Freight. In this context, the FR8RAIL project, is working on the “Development of Functional Requirements for Sustainable and Attractive European Rail”. To overcome these limitations, among other technical areas, the communications of the freight train is involved. This paper deals with the analysis of the and mainly with the evaluation of the technologies currently available. This will lead to the definition of the future freight train communication as an outcome of FR8RAIL project that will positively contribute to and support the Shift2Rail goals to strengthen the role of the freight rail transport.

This paper shows the strategy and results of the simulation of the Train integrity determination system into the on-board ETCS. It first shows the Smart Train Positioning System (STPS), a GNSS based on-board system that determines the the train integrity. Then, scenarios are derived for two different routes. After that, the test setup based on the ETCS on-board unit virtual laboratory is explained. Finally, the results show that the on-board ETCS equipment is able to detect correctly the integrity loss and operates accordingly. Then, the capability of STPS of providing integrity information is proven and that leads to the conclusion that train's integrity can be determined on-board by using STPS.

An on-board Complementary Positioning System (CPS) has been proposed to overcome the limitation of GNSS positioning systems. This paper deals with the test phase of CPS to guarantee the localization functions in areas in which GNSS signals are not available. In order to analyze the suitability of CPS its performance in a railway operational line has been evaluated. The CPS is based mainly on GNSS, Inertial Measurement Units (IMU) and Wireless Communications Technologies (WCT) as input sources for localization. The field tests have been carried out in an operational regional line and availability has been increased as it was the purpose.

In order to assess the performance of the wireless communication systems, a railway line is characterised through the identification of electromagnetic interferences (EMI). The aim of this paper is to show the strategy to identify EMI on field as well as the results obtained. First, the need of the analysis and the objectives of the measurement campaign in a non-electrified Italian Regional Railway line between Caligari and San Gavino are shown. After that, the measurement setup developed for the tests is described. Then, the description of the measurement campaign carried out is exposed. Finally, the measurement results are presented. The results show that the frequency bands of GSM, UMTS and Italian 4G are in the frequency ranges where the highest powered signal (around 800 MHz–900 MHz, 1.8 GHz and 1.9 GHz), on the other hand GPS L1 and Galileo E1frequency band is not impacted by any kind of interference signal.

This paper presents the implementation and validation of a complete AoA (Angle of Arrival) system. The AoA system is typically used together with smart antenna technology. In this paper the AoA system is part of a mobile wireless communication positioning system. The implementation includes the array antenna, the front ends and the AoA estimation block, which uses the MUSIC algorithm. Furthermore, a complete AoA system model has been developed, and used to find the optimum configuration of the AoA system. The AoA system has been validated using the model implemented in MATLAB.

Communication technologies are in continuous evolution and as well, the different applications making use of them. In order to succeed with the roll-out of the communication-based applications, it is required that the communications technologies are intensively tested and validated before deployment. Current strategies for testing and validation cover field tests and laboratory tests. Railways is also taking advantage of the communication technologies evolution, and therefore, there is a need for having testing and validation strategies adapted to the railway environment, especially for safety-critical applications. Field tests and laboratory tests also apply in Railways. In the frame of laboratory tests, this paper includes an overview of different network emulators existing currently in the market. Furthermore, an analysis of the gaps of the network emulators with regards to the needs of the railways environment is also included. The goal of this paper is to show that network emulators are a flexible cost-effective solution for communication technologies testing purposes. Additionally, this paper also shows that there is a need to adapt current emulators to the railway environment in order to test and validate the future railway applications based on communication technologies.

Recently, the first successful deployment of a fully automated commercial freight train operation was announced. This is the world’s first automated heavy-duty and long-haul rail network. It’s an impressive achievement, but why has it taken so long to achieve this when driverless urban metros have been in operation for more than 50 years? Although urban metros and freight trains are vehicles moved on rails, their operation and environment differ significantly. Metros operate in closed rail networks, while freight trains operate in open rail networks. However, the same taxonomy is often used to classify automation interchangeably in both environments. This paper provides context and an overview of driving automation in freight rail and reviews the existing taxonomies. This paper starts by providing context with an overview of the general process of driving a vehicle by delimiting its different stages. Next, we describe the overall process of driving a freight train to show the distinctive features of its setup and operation. In this analysis, we will point out the essential differences between open and closed rail networks, and the tasks that can potentially be automated. Additionally, we examine the evolution of level-based automation taxonomies and review those that have been proposed exclusively for driving automation in open and closed railway networks. Our objective is to provide a thorough summarization of the most relevant taxonomies to advance the definition of a suitable taxonomy and framework to classify automation capabilities in rail freight transport and identify some complex challenges ahead.

The European initiative Shift2Rail (S2R) joins efforts for smart and sustainable growth in the railway sector by fostering research and innovation. Specifically, the project FR8RAIL within the Innovation Programme 5 (IP5)'rail freight' of S2R aims to remove limiting factors of rail freight transportation. The work presented here is part of FR8RAIL and addresses the use and implementation of positioning strategies for rail freight transportation. Freight localization services based on on-board positioning, for example, can facilitate logistic optimization schemes that rely on continuous position and speed information. No extra trackside infrastructure is required, which reduces implementation and maintenance costs. The paper describes the challenges and requirements of on-board positioning strategies for the use in rail freight transportation and presents solution concepts (positioning requirements, hardware architecture, algorithms) for a more competitive rail freight.

GNSS have already been successfully used in safetycritical aviation and maritime applications. However, GNSS suffers from Line-Of Sight (LOS) problems. This causes a problem for railway use in tunnels, covered stations, cuttings etc. When the trains travel in these areas, the reception of NLOS (non-LOS) signals and lack of LOS signals not only affects GNSS availability, but also positioning accuracy and integrity. Therefore, the use of GNSS alone cannot reach the ETCS (European Train Control System) level 3 requirements for train location. To compensate the GNSS deficiencies, the Smart Train Positioning System (STPS) has been developed in the European Commission EATS (ETCS Advanced Testing and STPS) project. The STPS is based on two steps: firstly, the GNSS positioning is integrated with the WCT (Wireless Communications Technology) positioning on every coach of the train; secondly, a hybrid algorithm is developed to derive the “Front” and “Rear” position of the train by combining all hybrid GNSS/WCT train coach solutions. The KFMI (Kalman Filter Measurement Innovation) is an algorithm developed for multi-constellation GNSS positioning and integrity. KFMI includes an innovation Fault Detection and Exclusion (FDE) technique and a comprehensive integrity algorithm, to provide continuously accurate positioning and high integrity performance. Another characteristic of the STPS system is the ability to use WCT to locate the train. The WCT uses both GSM-R (Global System for Mobile Communications – Railway) and UMTS (Universal Mobile Telecommunication System) technologies. GSM-R and UMTS are mobile communications systems that can also be utilised to provide coarse positioning in any location served by the networks involved, often including those areas in which GNSS is unavailable. The novel WCT algorithm is developed especially including the calibration from the GNSS solution to improve the positioning accuracy. For the Train Integrity and Train Standstill Monitoring applications, the STPS core function brings together the outputs from the STPS Hybrid GNSS/WCT from the train’s constituent coaches and processes these to obtain consolidated or value-added front and rear end train positions. Therefore, if one of the GNSS/WCT train coach solutions is poor or unavailable, the front and rear end train position can still benefit from other coaches. Additionally, in case of the train integrity being broken, the availability of the front and rear end train positions could provide the vital information for the rescue. From the test results, we can see that the GNSS KFMI algorithm has better availability, accuracy and integrity when extra constellations are added. The hybridization with WCT then provides 100% availability. Integrity can also be provided by the hybrid GNSS/WCT algorithm in urban areas and tunnels. Therefore, the STPS approach has the potential to provide the EVC (European Vital Computer) kernel with train positioning and integrity information to allow migration from ETCS level 2 to level 3. Besides that, STPS could also be used in ETCS Level 2 to provide train positioning.

This article focuses on a novel Advanced Train LocAtion Simulator (ATLAS) for on-board railway location using wireless communication technologies, such as satellite navigation and location based systems. ATLAS allows the creation of multiple simulation environments providing a versatile tool for testing and assessing new train location services. This enhancement reduces the number of tests performed in real scenarios and trains, reducing the cost and development time of new location systems as well as assessing the performance level for given tracks. The simulation platform is based on modular blocks, where each block can be replaced or improved. The platform uses Monte Carlo Simulation to generate results with statistical significance. This implementation allows the modification of the development platform to cover multiple requirements, such as, ranging errors in the input parameters or including other positioning technologies. In this paper, the generated input parameter errors have been taken from the results of the field tests realized by the 3GPP ensuring the validity of the used parameter errors. However, these could be easily adapted by the user to particular characterized environments. Case studies for the validation of ATLAS will be also introduced, including preliminary results related to the use of Global System for Mobile communications in Railway (GSM-R) and Universal Mobile Telecommunications System (UMTS) technologies for positioning. The validation stage provides a way to test the platform functionalities and verify its flexibility. The versatility of the platform to perform simulations using same configuration parameters for different case studies can be highlighted. Furthermore, first conclusions are drawn from the obtained results. The characterization of the infrastructure for the simulation and the performance improvement of the location systems in the tunnels (e.g., by including Inertial Measurement Unit (IMU)) are necessary to achieve accuracy levels that can be valid for ETCS level 3.

The present document constitutes the first issue of Deliverable D2.1 “Scenarios and User Requirements” in the framework of the Project titled “Autonomous Indoor Outdoor Safety Tracking system” (Project Acronym: AIOSAT; Grant Agreement No 776425). This document has been prepared to give insight in the way fire brigades in Europe work. The document clarifies the differences that have been observed between the firefighter brigades among the countries participating in the project and even within countries, among the regions. With such differences, three representative scenarios are presented and the end user requirements are described for them.

AIOSAT Factsheet v1 (Month 3 of the project)