Optimization of FBG sensor sensitivity for disaster prevention in pipelines

Pipelines are widely used worldwide and may represent an environmental issue because of lickage induced by either natural events such as earthquakes and landslides or thief fraudulent activity. In particular the last instance involve use of a drill on the pipeline which could be detected by a vibration sensor. In the paper it will be shown that vibration sensors based on FBG is a more convenient solution with respect to conventional sensors particularly when the pipes are buried or exposed to harsh environment. In fact FBGs are basically made of glass and can therefore easily withstand chemical attack from many substances. In this paper we show how to improve the sensitivity by increasing the amplification factor.