Long term evolution in high speed railway environments: Feasibility and challenges

Long Term Evolution (LTE) is considered to be the natural evolution for the current Global System for Mobile Communications-Railways (GSM-R) in high speed railway environments, not only for its technical advantages and increased performance, but also due to the current evolution of public communication systems. In railway environments, mission critical services, operation assistance services, and passenger services must be supported by reliable mobile communication systems. Reliability and availability are key concerns for railway operators and as a consequence, railway operators are usually conservative adopters of information and communication technologies (ICT). This paper describes the feasibility of LTE as a successor to GSM-R for new railway mobile communication systems. We identify key features of LTE as a technology and analyze its ability to support both the migration of current railway services and the provisioning of potential future ones. We describe the key challenges to address specific requirements for railway communication services including the provisioning of voice service in LTE networks, handover performance, multicast multimedia transmission, and the provisioning of group communications service and railway emergency calls.