Open AccessDiaphragm-based optical fiber sensor array for multipoint acoustic detection
Author(s) -
Jingyi Wang,
Fan Ai,
Qizhen Sun,
Tao Liu,
Hao Li,
Zhijun Yan,
Deming Liu
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.025293
Subject(s) - fiber optic sensor , diaphragm (acoustics) , multiplexing , optics , optical fiber , materials science , distributed acoustic sensing , sensor array , demodulation , acoustics , sensitivity (control systems) , directivity , vibration , computer science , electronic engineering , physics , telecommunications , engineering , channel (broadcasting) , machine learning , antenna (radio)
Multipoint acoustic sensing system plays an important role in industrial applications. Here, a diaphragm based optical fiber sensor array is proposed, in which each sensor tip is made of 10-layer graphene diaphragm and optical fiber pigtail, with the compact size of about 2.5 mm in diameter. In particular, coherent phase detection is adopted to improve detection signal-to-noise ratio (SNR) and eliminate the demodulation dependence on structural parameters of sensor tips, and thus to achieve the multiplexing ability. Through time division multiplex (TDM), a multiplexing capacity up to 248 in theory can be realized, which is the first time to theoretically demonstrate large-scale acoustic sensor array for diaphragm based fiber sensor by phase detection, to the best of our knowledge. A prototype of 2 *2 sensor array is built to demonstrate the acoustic sensing performance. The field test results show excellent acoustic sensitivity of higher than -136 dB re 1 rad/μPa within the frequency range of 300 Hz~15 kHz, as well as the MDP of only 75 μPa/Hz 1/2 . Besides, good temperature stability and wide directivity are demonstrated. The proposed sensor array is promising in sound source localization, where the positioning accuracy of 3.55 cm is successfully realized.