Field Evaluation of MCX Implementations for the Future Railway Mobile Communication System

The Future Railway Mobile Communication System (FRMCS) will be the successor of GSM-R for mobile train-to-ground communication in railway operations. It will utilize 3GPP’s Mission Critical Services (MCX) framework to add several railway specific functions, such as point-to-point and group calls, location based communication and prioritization of certain services, to the 5G-based transport stratum. While the standardization of FRMCS and MCX is still ongoing, first railway specific implementations of MCX over 5G are being realized and tested. Proof-of-concept experiments and field trials are a crucial part of the FRMCS system verification which is still at its beginning. The partners DB Netz AG, Nokia, Kontron Transportation and Funkwerk, as part of the sector initiative Digitale Schiene Deutschland have established an R&D cooperation and implemented a first FRMCS network in DB’s Digital Rail testbed, which is located in the Erzgebirge region, Germany. This paper presents an early deployment and first measurement results of a FRMCS network, focusing especially on the MCX part of the system integrated with a 5G standalone network.