Study on key technologies of GNSS-based train state perception for train-centric railway signaling

The application of Global Navigation Satellite Systems (GNSSs) in the intelligent railway systems is rapidly developing all over the world. With the GNSS-based train positioning and moving state perception, the autonomy and flexibility of a novel train control system can be greatly enhanced over the existing solutions relying on the track-side facilities. Considering the safety critical features of the railway signaling applications, the GNSS stand-alone mode may not be sufficient to satisfy the practical requirements. In this paper, the key technologies for applying GNSS in novel train-centric railway signaling systems are investigated, including the multi-sensor data fusion, Virtual Balise (VB) capturing and messaging, train integrity monitoring and system performance evaluation. According to the practical characteristics of the novel train control system under the moving block mode, the details of the key technologies are introduced. Field demonstration results of a novel train control system using the presented technologies under the practical railway operation conditions are presented to illustrate the achievable performance feature of autonomous train state perception using BeiDou Navigation Satellite System (BDS) and related solutions. It reveals the great potentials of these key technologies in the next generation train control system and other GNSS-based railway implementations.