Optical Fiber Fabry-Pérot Interferometer and its Application to Railway Transport

The design and method of preparing the optical fiber sensor are presented. The optical fiber sensor is based on a Fabry-Pérot interferometer. An optical cavity of the interferometer is formed by single-mode optical fiber. The sensor, connected to the measuring unit, is placed on the foot of the track between sleepers. The functionality of the sensor was verified by passing a trainset consisting of a diesel locomotive and four wagons. From the received signal it is possible to determine the presence of the train at a given time, the number of axles, the speed of the train and to estimate the load of individual axles. Due to the simple installation and multifunctionality of the proposed sensor, the sensor appears to be a good candidate for monitoring railway traffic.