Open AccessMulti-longitudinal mode fiber laser digital vibration-sensing system based on a multi-carrier modulation/demodulation technique
Author(s) -
Yu Guo,
Xiaowei Mao,
Song Shu-lin,
Yi Ni,
Haodong Wu,
Xiang Fei Chen
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.405439
Subject(s) - demodulation , universal software radio peripheral , vibration , modulation (music) , frequency modulation , acoustics , signal (programming language) , computer science , electronic engineering , optics , channel (broadcasting) , telecommunications , physics , engineering , software defined radio , radio frequency , programming language
A multi-longitudinal mode fiber laser sensor (MLMFLS) system based on a digital modulation/demodulation technique is proposed. To the best of the authors' knowledge, this is the first digital vibration-demodulation system ever reported by a MLMFLS system. Multiple beat frequency signals (BFS) generated by the MLMFLS work as signal carriers of applied vibration signals. The vibration signals modulated on several BFS at different frequencies are simultaneously demodulated based on a multi-channel digital down-conversion technique by utilizing the digital universal software radio peripheral (USRP). The demodulated vibration signals from different signal channels are superposed by the USRP. Signal-to-noise ratio (SNR) of output vibration signal is highly improved, which increases sensing stability and accuracy of the system. This is really important for sensing of vibration signals that have an extremely low frequency or weak energy. Measurement results demonstrate that the sensing system has an excellent low frequency vibration-sensing capability, simple structure, high SNR, stability and accuracy.