Qualification of satellite-based localization systems for railway safety-related applications

GNSS plays a promising role for providing continuous as well as safety- and liability-critical localization of trains in safe train control systems. Therefore, an evaluation of the GNSS measurement quality becomes necessary for the safety acceptance of the localization function and further for the localization system. Currently, the railway environment is challenging for GNSS receivers because of the signal propagation route along the transmission path, such as multiple obstacles along and above the railway track etc. Those environments require a detailed examination to define the necessary characteristics of a train-borne localization unit. For this purpose, a tool chain has been developed to model the environment in an efficient way on the basis of satellite imagery. The developed methodology allows a receiver-independent evaluation of the environment.