Nokia Completes First 1900 MHz 5G Live Call on Deutsche Bahn Test Track Supporting FRMCS Radio
In a new benchmark for the rail industry, Nokia has successfully performed the world’s first 5G call over 1900 MHz (n101) 5G radio network deployment on a live outdoor test track, marking a major milestone in the industry’s transition from GSM-R to next-generation rail communications.
www.nokia.com
This marks a significant step in the industry’s transition from the legacy Global System for Mobile Communications for Railway (GSM-R) to the Future Railway Mobile Communication System (FRMCS) standard, as Nokia’s solution meets the forthcoming specifications of the new railway standard.
FRMCS will become the next-generation global standard for mobile communications on railways. Designed for real-time, mission-critical communications between infrastructure and trains, and with built-in security and high reliability, it enables enhanced automation, new digital applications, and secure cross-border communication.
Christian Schwass, Solution Manager from Nokia, explains:
"The real distinction between GSM-R and FRMCS lies in the technology and architecture. GSM-R was based on 2G GSM, with additional railway-specific requirements layered on top, such as mission-critical communications, group calls and train control features that standard GSM couldn’t support. FRMCS is a completely new architecture. It separates transport and services, with the transport layer handling how data moves from the train to the network, and the service layer delivering functions like group calls and train operability as independent software applications. This means FRMCS is no longer tied to a specific radio technology and can operate over 4G, 5G and potentially future technologies such as 6G."
Live Test Track Deployment with Deutsche Bahn
Nokia’s commercial 5G solution includes 1900MHz (n101) 5G radio network equipment from its AirScale portfolio and an optimised 5G standalone (SA) core. After a successful pre-FRMCS 5G trial with Deutsche Bahn (DB), the solution was deployed at DB’s digital railway test field in the Ore Mountains (Erzgebirge, Germany). It will also support the test trials planned in the European FP2-MORANE-2 project for the validation of the FRMCS standards.
From a radio perspective, there was no major difference compared with other deployments using different bands, Schwass notes. “What made this significant was that it was our first deployment on a live railway track, requiring installation and integration in a real operational environment for the first time. That naturally brought technical challenges, but these were resolved successfully, including smooth handovers.”
Testing in Real-World Conditions
The initial phase focused on basic network functionality, testing handovers and confirming continuous coverage and connectivity from the train through to the core network across the full length of the track. This culminated with the first UE attachment and call over the network, being performed already in December 2025. Prior to this achievement, several stages of lab pre-testing with early n101 capable modem versions have been taking place.
Schwass says:
"This was our first live FRMCS one-to-one call in a real customer environment. After years of development, pre-testing and lab work involving our R&D teams, we were able to deploy the system on an operational track using FRMCS equipment and successfully complete live calls.
Testing in an R&D or customer lab is very different from operating on a live railway, he notes. In the lab, equipment is positioned close together and conditions are controlled. On a live track, you can see how the system truly behaves end to end: from onboard equipment on the train through the network core to mission-critical applications."
Schwass continued:
"That real-world testing gives us insights that can’t be replicated in a simulated environment and confirms that the system works as intended, with no losses or disconnections."
Following this initial functional testing phase, the focus is now shifting towards performance evaluation, with the next stage to assess how the system performs under real operational conditions.
This will include detailed testing of latency, quality of service and throughput, providing insight into how the network behaves beyond basic connectivity. By analysing these performance parameters, the team aims to understand whether the system can consistently deliver the levels of reliability and responsiveness required for operational use, as well as how it performs across the full length of the track under normal conditions.
Accelerating the Industry’s FRMCS Transition
Designed for a smooth migration from GSM-R to FRMCS, Nokia’s new 5G radio supports strategic coexistence, enabling railways to migrate to 5G communications alongside legacy systems like GSM-R with no disruption. The proof of concept (PoC) in collaboration with DB marks a significant step towards operational FRMCS readiness. While final specifications are still being completed, the core architecture and hardware are already in place and proven in a live railway environment. Any remaining adaptations will be addressed through software updates, allowing the same infrastructure to be reused and aligned with the finalised standards as they’re released, notes Schwass.
Crucially, this PoC demonstrates that such deployments are not only possible, but also practical, showcasing that the technology is ready to support early rollout and continued evolution, rather than waiting for final specifications before taking action.
This milestone extends beyond a single deployment to show the wider rail industry tangible evidence that FRMCS technology can be implemented, tested and refined in real-world conditions today.
Schwass concludes:
"From a Nokia perspective, it represents our contribution to the broader industry vision helping to build confidence, accelerate progress and support a coordinated transition towards next-generation rail communications."
www.nokia.com
