RAILWAY COMMUNICATIONS Transition from global system for GSM-R to FRMCS

Limitations of GSM-R

While the assigned radio frequencies for GSM-R limit its capacity, increasing interference from public networks is further hampering the use of GSM-R. These limitations include:

1. Interference

The interference between GSM-R and other public networks increases as both railway and public operators desire good coverage along the rail tracks. Instead of cooperating in network planning, railway and public operators fight for the coverage. This could result in severe impairment of voice and data communications as well as network loss over several hundred meters of track. Theoretically, such interference can be avoided if public operators do not use frequency bands adjacent to those of GSM-R for the areas close to rail tracks; however, this is not well implemented in practice. In future, interference may increase owing to the growth of GSM-R network deployment and the potential growth of public networks.

2. Capability

As a narrowband system, GSM-R cannot provide advanced services and adapt to new requirements. The maximum transmission rate of GSM-R per connection is 9.6 kbit/s, which is sufficient only for applications with low demand; message delay is in the range of 400 ms, which is too high to support any real-time application and emergency communication. Future new services such as real-time monitoring require a wideband system to have a larger data rate and short delay.

3. Capacity

GSM-R’s 4 MHz bandwidth can support 19 channels of 200 KHz width. This is sufficient for voice communication, as voice calls are limited in time and do not occupy resources continuously. However, the current capacity is insufficient for the next-generation railway system, where each train needs to establish a continuous data connection with a Radio Block Center (RBC), and each RBC connection needs to constantly occupy a one-time slot. The radio capacity can be increased by using more spectrum resources.

Despite the above shortcomings, GSM-R has been a great success worldwide with more than 100,000 Km of railway tracks operated every day in Europe alone. Nevertheless, while the needs of the railways are constantly evolving in terms of capacity, latency, and safety, the evolution of railways telecom standards remain dependent on the evolution cycles of the commercial telecom industry with an end of support for GSM-R planned by 2030. These considerations led UIC to launch the first studies for a successor to GSM-R by 2012, named FRMCS. The new set of User Requirements Specifications (URS) focused mainly on rail communication needs as a basis for the development of the GSM-R successor.

Need for Transition: GSM-R to FRMCS

Being 2G-based (voice and SMS), GSM-R is not bandwidth-efficient. 5G, on the other hand, is a better option to replace GSM-R in the future. It offers multiple advantages over GSM, being best suited for data communications besides efficient network architecture, highly reduced packet delays (crucial for ETCS messages), and high throughput radio access due increased spectral efficiency through advanced multiplexing and modulation.

The predicted obsolescence of GSM-R is by 2030, while the life expectancy of ETCS is 2050. UIC is, therefore, laying the foundations of the FRMCS with the following goals:

Hence, UIC has been working on defining a FRMCS as part of 3GPP Release 16 standards to support automatic train operations, virtual coupling, tele maintenance, etc. Both GSM-R and FRMCS systems will coexist for a considerable period, where both communication services will be used.

Migration to FRMCS

The 5G Rail project, led by an industrial consortium of 18 rail and telecom partners across 11 countries, aims to validate FRCMS V1 for the railway sector. Led by UIC as coordinator and technical authority, it began in November 2020 and will conclude in April 2023 with a total investment of 14 million euros.

UIC, along with European Commission Directorate-General for Digital Technology (DG Connect), formed the 5G Rail consortium, bringing together railway operators (German Rail-DB, French National Railways–SNCF, Swiss Federal Railways–SBB, Austrian Federal Railways–ÖBB, and Infrastructures de Portugal-IP) and telecom industry players (Nokia, Kotron, Alstom, Thales, Siemens, CAF, Teleste, and European Rail Industry– UNIFE), to work on prototyping the FRMCS system, simulation, and field test phases in France and Germany. A 5G Rail Advisory Board has been set up to involve as many rail sector stakeholders as possible. The first members to join the committee are Network Rail, RFI, ADIF, Infrabel, Trafikverket, SZ, Rail Baltica, Shift2Rail, European Railway Agency (ERA), UNISIG, ETSI TCRT, with many others set to request membership soon.

The FRMCS ecosystem relies on a new onboard telecom system called the TOBA (Telecom On-Board Architecture) Box. TOBA offers a single harmonized system of groundto-train communications, where a number of different physical communications interfaces coexist within the locomotive for voiceactivated GSM-R applications and ETCS signaling. TOBA will act as a “hub” for the “digital railway” within the train, taking charge of all incoming and outgoing telecommunications and supplying sufficient bandwidth and Quality of Service (QOS) for all future onboard applications with frequencyhopping, cybersecurity functions, and other features.

FRMCS: Current Status and Next Steps

(a) Technical developments:

• Current status

- UIC has delivered the user requirements specification after consulting its stakeholders

- There is an ongoing evaluation to assess FRMCS compatibility with 3GPP releases

• Next steps

- Finalize the technical specifications and architecture of FRMCS

- Address how the railway-specific applications will be developed and tested

- Develop and test FRMCS

(b) Migration:

• Next steps

- Specify how to handle backward compatibility to GSM-R and ensure business continuity

- Define the on-board solution, a prerequisite/important parameter for a successful migration

- Define the rules of the game for an IM to be able to close down its GSM-R network in favor of FRMCS

(c) Spectrum:

• Current status

- ETSI is currently building a spectrum requirements document to be presented to frequency management organizations. This step is essential to get the appropriate spectrum for the future system

• Next steps

- Continue the process to ensure that IMs have access to the required spectrum to ensure a smooth migration and reuse of their existing infrastructure

(d) Finance and legal:

• Next steps

- Specify how FRMCS prototyping and development will be financed

- Develop a business case at the European level to support the migration from GSM-R to FRMCS

- Specify the legal framework of the new telecom environment (including which part of FRMCS should be part of TSI CCS)

FRMCS Offerings by Cyient

(a) Passenger Information System (PIS): Digital signage, Wi-Fi connectivity, infotainment

On board the moving train, the following services using near-real-time information can be provided as part of the PIS:

• 3D wayfinding, event details, points of interest, and emergency information

• Travelers can also connect directly to station or operation officials and talk to a live person on the screen

• In railway stations with lower-cost broadband or underdeveloped/unavailable internet infrastructure, free public Wi-Fi kiosks can help stations bridge the digital divide

(b) Connectivity and network communications: 5G technology is a step-change in mobile networking for both consumers and industry, offering users fast download speeds, low latency, and data sharing in near-real time, thereby allowing for radical advancements in connectivity on board moving trains. For example, downloading a 2-gigabyte high-definition movie in less than 20 seconds on a phone is now becoming a reality for train passengers. Railways with 5G infrastructure can offer 5G Wi-Fi to passengers on board. To improve passenger experience, train operators are looking to expand the reliability and availability of on-board WiFi, enabled by super-fast and on-board broadband powered by 5G technology. In addition, when access to 5G is not possible (due to white zones, tunnels, etc.), on-board servers can maintain services, thanks to their new edge computing performance.

(c) Infotainment and Advertisement: Digital signage on board trains and within train stations can improve passenger experience and safety, shorten queues, optimize people flow and wayfinding, and improve labor efficiency and passenger experience. High-performance, environment-sensing display technology allows advertisers, retailers, and station operators to effectively monetize visual communications, engage passengers, and boost commercial revenue on board moving trains. Optimized near-real-time displays improve customer experience by providing information, entertainment, and wayfinding support. Modern digital infrastructure at the network edge helps deliver actionable, data-driven insights and support for applications and experiences for passengers on board the train.

(d) Smart ticketing and contactless journey through automated fare collection, access control, and touchless retail transactions on-board: Smart ticketing systems, part of the contactless journey, can be applied to rail transit and utilized on board moving trains. Passengers can use stored value cards that can be quickly charged through the gate at stations or on board, with the validator deducting fare from the contactless card automatically. The e-ticketing system can greatly improve the quality of intelligent traffic and transport efficiency by automating the entire ticketing management process for a railway. Smart ticketing systems allow for fare collection to occur through a credit card tap while on board the moving train, via a railcard on the train, or through a smartphone. The use of sensor beacons could eventually result in the removal of ticket barriers and signal an end to queues at the ticket machine in metro railway stations. Sensors on station platforms or onboard trains will be able to detect an app on passenger smartphones as they enter the station or board, automatically charging the correct fare and eliminating overcharges. Metro railway operators will be able to streamline backend billing and revenue management while better understanding metro train usage behavior through near-real-time data.

(e) Access control: With access control using biometric e-gates, passengers could board their train without a ticket or passport. With a simple glance at a high-resolution camera, the passenger's biometric ID would be recognized in a matter of seconds. The image would be securely sent to customers and border control for traveler verification, which would then match the data with the stored digital token captured during the initial immigration process. In a few seconds, the system would reconcile the passenger with the train, recognize the passenger as eligible to enter the train, and accordingly open the e-gate for the passenger to board. Digital passport technology will allow passengers to complete customs from on board the train prior to arrival in the country they are visiting. Digital signage and kiosks can display near-real-time public safety messages to warn travelers about evacuations, toxic gasses, or other emergencies. Railway station officials can use on-board cameras to measure and analyze passenger flow, improving railway safety and traveler experience.

(f) Passenger safety: Smart security functions can also enhance passenger safety and reduce public liability. For example, computer vision solutions can enable automated and safe platform screen door systems and train door systems on passenger trains and detect when passengers slip and fall. In addition, these solutions can help locate missing children in a crowd and can detect if children climb onto conveyor belts, fall on escalators or onto trackways, or enter restricted areas. The need for automated quarantine control can also be identified, as well as potential water spills and smoke and fire detection. This service remains available and effective, regardless of any disconnection from the Internet or the cloud.

(g) Predictive maintenance: Predictive maintenance for tracks, locomotives, trains, and equipment is an important safety and efficiency tool for railway operators. It uses near-real-time diagnostic data to plan maintenance cycles at an early stage through monitoring and the collection of data, helping railway operators to avoid operational breakdowns or failures. Downtimes and maintenance costs are reduced while the life of tracks, locomotives, trains, and equipment increases. Passengers, in turn, benefit from improved reliability of railway operations.

(h) Driver assistance/operator distraction prevention: The natural demands of long-distance trips can leave railway operators fatigued and distracted, creating the potential for increased errors. It can be challenging for railway organizations to track the sleep patterns, energy levels, and/or behavior of drivers and operators. With the implementation of a computer vision AI-based solution, railways can use predictive analytics to detect face and eye signals that may indicate possible distraction and fatigue. These tools can help drivers, operators, and railway managers increase safety, prevent accidents, and protect assets. Detection of potential obstacles on railways is also critical. Automatic, near-real-time warnings require high performance and online video analysis so as to efficiently provide monitoring to the driver or to the automatic driving system.

(i) People counting: Getting from one place to another in a train station can create challenges for customers and train station stakeholders on a daily basis. Congestion, overcrowding, and the potential for crime can result in lost revenue and operational inefficiencies for stations, apart from traveler dissatisfaction. Using deep learning and AI through computer vision, stations can accurately monitor passenger traffic flow for enhanced analytics that aid in decision-making for station planning and operations. This includes assigning the right quantity of staff during traffic spikes and protecting people and assets by detecting potential issues before they happen.

(j) Cargo tracking: A constant challenge for travelers is the way their cargo is handled. If the cargo of a passenger is transferred to the wrong connecting train, it can be costly and detrimental to the reputation of the company. An operator using computer vision can track passengers’ cargo and notify other operators if the cargo is misplaced, helping to ensure on-time delivery to the correct destination.

(k) Asset tracking: For safety and efficiency, it is important for railways to know where their assets are at all times. With so many different assets constantly on the move, railways face challenges, including delays, lost equipment, theft, and errors. Leveraging asset tracking through computer vision can reduce the dwell time of stationary locomotives, increase operational efficiency, and can track all of a railway system’s assets in near-real-time to maximize utilization and reduce cost.

(l) Enhancing security: Enhanced security at the platform level and improved security of data and communications are essential to ensuring success within railway systems. In this case, vision applications help railways enhance security, measure the flow of people, enable smart parking at stations, and provide automated access control. Railway operators can use optical sensing, thermal detection, alarm systems, and system linkage to protect the perimeter. Track monitoring identifies arriving and departing trains with optical sensing, thermal detection, long-range viewing, and panoramic mode. Parking lot security helps protect parking lots and control entrances using license plate recognition, optical sensing, and parking guidance. Railway operators can also control traffic and monitor vehicles using optical sensing, license plate recognition, suspect car alarm, information issuing, and traffic incident detection. Terminal monitoring allows railway operators to monitor retail sites, passenger behavior, e-passport gates, and luggage systems. Smart security at train stations and on board trains can use biometric indicators to confirm identity as well as provide alerts about people of interest or suspects in a crowd in an uncontrolled environment or for abandoned bag detection. Alerts for any overcrowding incidents with people-counting based on zones can enhance rescue operations during emergencies. Trolleys that have been left where they should not be, as well as suspicious behaviors such as loitering, sudden crowd gathering, or man-down problems, are also detectable. With individual privacy as a fundamental concern, all biometric and personally identifiable data are fully anonymized at the source. Stored and transmitted data are encrypted using state-of-the-art algorithms powered by on-board hardware accelerators.

Recommendations

Harmonized frequency bands for FRMCS are now under standardization in 3GPP as 5G bands which is a base to enable a sustainable ecosystem of chipsets for mobile devices. With an advanced capability of bearer flexibility, different bands, such as satellite or mobile network operator sharing models, can be considered as options to define successive business models. FRMCS is developed as an IP-based technology towards the adoption of modernized transmission network functionality. One of the fundamental specs of the 3GPP 5G standard is to have virtualized, software- and cloud-enabled networks that can support such an evolution while benefiting from IT-based technology and migration of GSM-R and 5G-compatible products. The railway domain can greatly benefit from synergies with other industry domains with respect to enabling missioncritical networks and applications. The 3GPPdefined Mission Critical Communication standards will allow for synergies in products and solutions based on solid standards.