RAN planning for GSM-R and 5G/FRMCS ensures the high-speed, continuous and reliable communication that railway operations and safety demand, across trackside infrastructure, tunnels, stations and the transition to next-generation private railway wireless networks.
Wireless Communication Network for Railways
In the context of railway networks, RAN planning refers to planning of the Radio Access Network that enables the communications of railway operations, such as signaling and railway mobile communication systems. The railway industry has unique requirements around safety, performance, and reliability, thus requiring special considerations for RAN planning.
Any wireless communication network for railways must be robust, secure, and support continuous communication. It’s crucial for coverage to be uninterrupted along the entirety of the railroad tracks, including in tunnels, under bridges, and in remote or mountainous areas.
Continuous Coverage
Railways often travel through remote and difficult terrain. Ensuring the signal remains strong and uninterrupted across all areas of the railway, including tunnel and bridge crossings, is critical for maintaining communications for both safety and operational efficiency.
High Reliability and Redundancy
In addition to being highly reliable, the network must also have sufficient redundancy measures to prevent any communication failures. This is vital for critical safety systems and for managing train operations.
Support for High Mobility
The high-speed mobility of trains is another unique consideration. The RAN must be able to handle high speeds seamlessly and reliably. This involves managing handoffs between cell sites without dropping calls or data sessions, which is crucial for continuous communication.
Capacity Planning, Quality of Service, and Interoperability
TRAN planning for railways must also account for varying load demands, which include increased demand at peak times and significant fluctuations depending on passenger volume train schedules. The Quality of Service (QoS) further requires the prioritization of critical communications—such as those for emergency services—over less critical services. Since the rail industry is transitioning from older technologies like GSM-R (Global System for Mobile Communications – Railway) to newer ones like FRMCS (Future Railway Mobile Communication System based on 5G), it’s also important that RAN planning accounts for compatibility with both technologies and standards.
RAN Planning for Railway Networks with Atoll
Atoll’s comprehensive network planning includes detailed coverage and capacity analysis for GSM-R and 5G wireless technologies, including environments such as railway stations and tunnels. Its ability to model both the outdoors and indoors—including the structure and materials of buildings—enables it to accurately predict signal propagation and ensure reliable communication along railway tracks. Atoll is a 5G network planning software that can also model both GSM-R and FRMCS technologies concurrently, allowing both systems to be operational simultaneously across the railway network and helping to prevent any service disruptions during the transition period.
Planning railway private networks and the GSM-R to FRMCS migration
The rail industry is managing two challenges simultaneously: maintaining GSM-R networks that remain the operational backbone for train control and signalling across most of Europe, while planning the transition to FRMCS — the Future Railway Mobile Communication System based on 5G. Full network-wide deployment is expected across major European networks by the end of the decade.
Planning the dual-technology transition means both systems must operate concurrently without service disruption. Atoll models GSM-R and FRMCS in a single project, allowing the full transition: trackside coverage, tunnel propagation with leaky feeder and radiating cable, high-speed handover parameters and station indoor coverage, to be validated together before any migration phase begins.
For site-level private wireless network deployments within the railway context, for example, a maintenance depot, a station complex, an operational yard requiring dedicated private LTE or private 5G coverage, Atoll One handles indoor and outdoor planning in a single workflow.
Frequently asked questions
FRMCS (Future Railway Mobile Communication System) is the 5G-based standard that will replace GSM-R as the primary wireless communication system for railways. GSM-R is the current technology used for train control, signalling and operational communications across most European and international railway networks. FRMCS provides higher capacity, lower latency and support for modern railway applications including advanced train control, video surveillance and passenger connectivity. The transition from GSM-R to FRMCS is underway. Planning both technologies concurrently, with no service interruption during the transition, is the central challenge for railway network teams.
Three things: the linear topology requires continuous coverage along the full route rather than across a bounded site; high-speed train mobility demands precise handover planning at speeds up to 300+ km/h; and the environments are highly varied (open terrain, tunnels, cuttings, stations) each with different propagation characteristics. A private railway wireless network must perform reliably across all of them simultaneously.
Railway tunnels use leaky feeder cable (radiating cable) or active DAS to propagate signal through enclosed environments where standard trackside antennas cannot reach. Atoll models both configurations within the full railway network plan, allowing tunnel coverage to be validated alongside trackside macro coverage as part of a unified simulation.
Atoll is the primary tool for railway wireless network planning. It handles the national-scale topology, multi-technology GSM-R and FRMCS concurrent planning, and the full range of railway environments that rail operators require. Atoll One is used for site-level private wireless network deployments within the railway context where indoor and outdoor planning for a bounded site is the main requirement.
FRMCS deployment is advancing across European rail network. Full network-wide deployment is expected across major European networks towards the end of the decade, with other regions following as the technology and standards mature.
