Radio Sensing in Electric Railways for Future 5G: An Smart Railways Use Case

Electric railways and Intelligent Transportation Systems (ITS) are a key use case for both current and future mobile communication systems, such as 5G and 6G, respectively. 5G sensing is mostly about spectrum sensing, whereas 6G is focused on a more advanced paradigm: Integrated Sensing and Communications (ISAC). In this paper, we provide some results from a low-cost OFDM-based spectrum sensing system designed to detect electric arcs and sparks generated by the pantograph-catenary contact on a subway train in real-world conditions. The results from the sensing system are validated using a video camera installed on top of the train. This paper describes both the testbed setup and the results obtained specifically related to radio sensing. This work is part of the Metro de Madrid SPARC Project, which focuses on innovative sensing solutions for pantographs.