Abstract

With the inherent advantages of small size, high sensitivity, immunity to electromagnetic interference and possibility of multiplexing the optical fiber based acoustic sensors find application in various fields, such as structure health monitoring, underground pressure monitoring and disaster forecasting [1]. Among various fiber acoustic sensing systems, diaphragm based systems mostly used due to their simple design and high sensitivity. Diaphragm based extrinsic Fabry–Perot interferometric fiber acoustic sensors with different kind of diaphragm materials, such as graphene, silver, and PET have been reported by various research groups [2–4]. However, these sensors require fabrication of a very thin and small diaphragm where handling is a concern, and also the sensing mechanisms are wavelength based, these requirements increase the complexity and overall cost of the sensing system.

© 2017 IEEE