Design and implementation of a safety communication network in railways with intelligent fault diagnosis

This paper presents a network that connects various safety sensors located on level crossings and in stations. These sensors are used to detect obstacles on the railway line and proximity between trains. The information is centralised in the operations and control centre(OCC). The network has been designed in sections, each of which consists of a dual bus structure, with the particular feature that if one of the buses fails, the packets are routed to the other. Fault detection on the network is performed using intelligent diagnostic techniques, applying the IEEE 1232-2002 standard. By examining the result of the diagnosis, it is possible to ascertain the optimal route from each sensor to the OCC. Monitoring is performed using active network techniques. The diagnostic system sends packets containing code that is executed at each node.