Feasibility Analysis of Wireless Technologies for Railway Signalling Systems

Railway operations are becoming increasingly automated and integrated through the usage of Information and Communication Technology (ICT). Advanced signalling systems enable the railway operators to increase the number of trains on the same track safely without large infrastructure investments. However, introduction of recent mobile telecommunication systems - such as LTE and UMTS-causes severe interference and capacity limitations to the GSM-R (standardized radio system for railway communication) in 400 railway stations around Europe. This paper investigates an alternative that can overcome the limitations of the GSM-R signalling system with the lowest use of operating power. The performance analysis of potential wireless alternatives including: LTE-R, WLAN, Bluetooth, IEEE 802.15.4 and ZigBee. These technologies were validated through their ability to meet the safety requirements set by ETCS (European Train Control System) standards. Preliminary results have shown that the low power technologies operating in the free band Industrial, Scientific and Medical band (ISM) can offer an efficient and low cost potential solution. The paper proposes a novel design for a railway signalling -based on ZigBee and RFID technologies-and presents an evaluation of the system flexibility, achievable range and rolling stock to trackside wireless link performance.