A survey on future railway radio communications services: challenges and opportunities
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paper_title: An overview of GSM-R technology and its shortcomings

paper_content:

Railway communication technologies undergo a revolutionary change bringing them from the analog to the digital era. The European Rail Traffic Management System (ERTMS) replaces numerous incompatible analog radio systems, classical side-track signs and legacy in-cab signaling with an integrated comprehensive solution. This paper presents an overview of GSM-Railways (GSM-R), which is the unified communication technology supporting ERTMS. Its shortcoming in terms of capacity and capability are discussed as a foundation for the need for further developments.
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paper_title: Using dataflow traceability between functions in the safety evaluation process

paper_content:

This paper deals with the safety evaluation process required by law for high safety related system in rail in Europe. A methodology is given to guide the independent analysis and evaluation process. In a general framework for requirement engineering process, the proposed methodology aims at speeding up the process of safety evaluation and to facilitate the work of the independent checker and of the assessor of the system in a systematic way. The methodology is based on a functional analysis approach using the exchange of dataflows. This methodology has been tested on the EU LOCOPROL research project signalling part and is given as an application case.
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paper_title: Survey of Wireless Communication Technologies for Public Safety

paper_content:

Public Safety (PS) organizations bring value to society by creating a stable and secure environment. The services they provide include protection of people, environment and assets and they address a large number of threats both natural and man-made, acts of terrorism, technological, radiological or environmental accidents. The capability to exchange information (e.g., voice and data) is essential to improve the coordination of PS officers during an emergency crisis and improve response efforts. Wireless communications are particularly important in field operations to support the mobility of first responders. Recent disasters have emphasized the need to enhance interoperability, capacity and broadband connectivity of the wireless networks used by PS organizations. This paper surveys the outstanding challenges in this area, the status of wireless communication technologies in this particular domain and the current regulatory, standardization and research activities to address the identified challenges, with a particular focus on USA and Europe.
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paper_title: Mobile relay in LTE-advanced systems

paper_content:

Voice and data communications on high speed vehicles encounter bad channel condition, high call drop rate, serious signaling congestion and excessive power consumption of UE. Mobile relay technology which features on-board relay node is expected to improve the quality of service for passengers. However, the design for fixed relay in LTE-Advanced system cannot meet the requirements of mobile relay. In this article, the architecture for mobile relay is presented. The key techniques of supporting mobile relay are investigated, such as the group mobility, the local service support, the multi-RAT and RAN sharing, with the corresponding solutions. The potential system optimization, for example, the self-optimization network, power saving, measurement and system information acquisition are also presented where the efficiency of mobile relay can further be improved. Simulation and numerical results demonstrate the feasibility of the mobile relay.
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paper_title: A Survey of Radio Propagation Modeling for Tunnels

paper_content:

Radio signal propagation modeling plays an important role in designing wireless communication systems. The propagation models are used to calculate the number and position of base stations and predict the radio coverage. Different models have been developed to predict radio propagation behavior for wireless communication systems in different operating environments. In this paper we shall limit our discussion to the latest achievements in radio propagation modeling related to tunnels. The main modeling approaches used for propagation in tunnels are reviewed, namely, numerical methods for solving Maxwell equations, waveguide or modal approach, ray tracing based methods and two-slope path loss modeling. They are discussed in terms of modeling complexity and required information on the environment including tunnel geometry and electric as well as magnetic properties of walls.
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paper_title: Challenges Toward Wireless Communications for High-Speed Railway

paper_content:

High-speed railway (HSR) brings convenience to peoples' lives and is generally considered as one of the most sustainable developments for ground transportation. One of the important parts of HSR construction is the signaling system, which is also called the “operation control system,” where wireless communications play a key role in the transmission of train control data. We discuss in detail the main differences in scientific research for wireless communications between the HSR operation scenarios and the conventional public land mobile scenarios. The latest research progress in wireless channel modeling in viaducts, cuttings, and tunnels scenarios are discussed. The characteristics of nonstationary channel and the line-of-sight (LOS) sparse and LOS multiple-input-multiple-output channels, which are the typical channels in HSR scenarios, are analyzed. Some novel concepts such as composite transportation and key challenging techniques such as train-to-train communication, vacuum maglev train techniques, the security for HSR, and the fifth-generation wireless communications related techniques for future HSR development for safer, more comfortable, and more secure HSR operation are also discussed.
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Title: A survey on future railway radio communications services: challenges and opportunities

Section 1: INTRODUCTION
Description 1: Briefly introduce the scope and significance of the survey in railway radio communications services.

Section 2: SAFETY SERVICES
Description 2: Discuss critical services related to train safety and public safety, including their requirements.

Section 3: SIGNALING FOR HIGH-SPEED TRAINS
Description 3: Highlight the state-of-the-art signaling systems for high-speed trains and related challenges.

Section 4: SIGNALING FOR SUBWAYS: CBTC
Description 4: Cover communications-based train control systems in subways and how they compare to signaling for high-speed trains.

Section 5: TRAMWAYS: INTEGRATION ON SMART CARS PLATFORMS
Description 5: Explain the potential future integration of tramways with smart car platforms.

Section 6: SIGNALING DATA OVER SATELLITES
Description 6: Explore the use of satellites for signaling data in railway communications, especially for low-density traffic areas.

Section 7: THE FAR FUTURE OF FREIGHT TRAINS: VIRTUAL COUPLING
Description 7: Discuss the concept of virtual coupling for freight trains and its potential impact on rail capacity.

Section 8: PUBLIC SAFETY IN RAILWAYS
Description 8: Describe the use of public safety communications systems in railways and their challenges.

Section 9: OPERATIONAL SERVICES
Description 9: Discuss the challenges and opportunities related to non-safety operational services for railways.

Section 10: PASSENGER INFORMATION/INFOTAINMENT
Description 10: Highlight the services that provide passengers with multimedia content and information.

Section 11: CCTV
Description 11: Cover the challenges and requirements of CCTV systems in railway operations.

Section 12: THE INTERNET OF THINGS
Description 12: Explore the potential and challenges of adopting IoT in railways for operational and maintenance purposes.

Section 13: SERVICES FOR PASSENGERS: INTERNET ACCESS
Description 13: Discuss the challenges and current solutions for providing Internet access to onboard passengers.

Section 14: MOBILE RELAYS
Description 14: Explain the use and benefits of mobile relays in improving cell coverage and spectral efficiency.

Section 15: SATELLITES
Description 15: Describe the advantages and limitations of using satellites for providing Internet access on trains.

Section 16: CYBER SECURITY
Description 16: Highlight the importance of cyber security in railway communications and related challenges.

Section 17: TECHNOLOGICAL ISSUES
Description 17: Discuss general technological challenges not specific to any one category of service.

Section 18: RADIO CONVERGENCE
Description 18: Cover the trend towards radio convergence to handle multiple services over a single radio system.

Section 19: WITHDRAWAL OF ONBOARD WIRING
Description 19: Describe the trend and advantages of replacing onboard wiring with wireless links.

Section 20: HIGH-SPEED SCENARIOS
Description 20: Discuss the specific challenges of maintaining reliable communication at high train speeds.

Section 21: CHANNEL MODELLING
Description 21: Highlight the importance and challenges of accurate channel modeling in V2I and V2V scenarios.

Section 22: CONCLUSION
Description 22: Summarize the key points discussed in the survey and present open questions and future research directions.

Section 23: IN MEMORY OF LEANDRO DE HARO
Description 23: Tribute to Leandro de Haro for his contributions to the field and research in antennas and communications.