Realization of an optical fiber Bragg grating microphone

We present an optical fiber Bragg grating (FBG) sensor suitable for the acquisition of high frequency vibrations, well exceeding also the highest end of the audio band. The optical sensing system employs a simple principle of operation based on intensity modulation and is implemented with off-the-shelf telecom devices. Then, advanced signal processing algorithms are used to mitigate noise and improve the sound analysis in the frequency domain. Experimental results validate the effective operation of the sensing system in practical applications.