Affiliation:
1. Southern University of Science and Technology
2. Chinese Academy of Sciences
3. Macau University of Science and Technology
4. Huazhong University of Science and Technology
5. Nanjing University
6. Pengcheng Laboratory
Abstract
We have proposed and demonstrated a weak acoustic signal detection technology based on phase-sensitive optical time-domain reflectometry
(Φ-OTDR). Non-contact acoustic signals transmitting through air gap between the sound source and the receiver are difficult to detect due to
fast attenuation. In order to improve the detection ability of non-contact weak acoustic signals, we demonstrate that multi-mode fiber (MMF)
is a better solution than single-mode fiber (SMF) benefiting from its larger core and higher Rayleigh backscattering (RBS) capture
coefficient. The frequency signal-to-noise ratio (SNR) has been enhanced by 9.26 dB. Then, with the help of 3D printing technology,
elastomers have been designed to further enhance the detection ability due to the high-sensitive response to acoustic signals. Compared with
the previous reported “I” type elastomer, the location and frequency SNR enhancement caused by our new proposed “n” type elastomer are
8.39 dB and 11.02 dB in SMF based system. The values are further improved to 10.51 dB and 13.38 dB in MMF and “n” type elastomer integrated
system. And a phase-pressure sensitivity of -94.62 dB re rad/µPa has been achieved at 2.5 kHz. This non-contact weak acoustic signal
detection technique has great application potential in the quasi-distributed partial discharge (PD) detection of smart grid.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Guangdong Province
Stable Support Program for Higher Education Institutions from Shenzhen Science, Technology & Innovation
Commission
Basic and Applied Basic Research Foundation of Guangdong Province
State Key Laboratory of Information Photonics and Optical Communications
Beijing University of Posts and Telecommunications
Open Projects Foundation of State Key Laboratory of Optical Fiber and Cable Manufacture
Technology
General Program of Shenzhen Science, Technology & Innovation Commission
Shenzhen Research Foundation
Subject
Atomic and Molecular Physics, and Optics