Laboratory Evaluation of a Phase-Otdr Setup for Railway Monitoring Applications

Abstract

Phase-sensitive optical time-domain reflectometry (phase-OTDR) has recently drawn increased attention for applications within the railway transportation sector. In this paper we present a laboratory approach to demonstrate the feasibility of an interrogator of vibrations along railways by means of fiber-optic cables. Contrary to the common use of piezo-electric phase modulators in laboratory setups, a vibration shaker is used to excite a plastic tube to which the fiber is attached. Measurement of event position and frequency is demonstrated in a range up to 7000 Hz.