{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,7]],"date-time":"2026-02-07T18:42:57Z","timestamp":1770489777854,"version":"3.49.0"},"reference-count":27,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2020,4,2]],"date-time":"2020-04-02T00:00:00Z","timestamp":1585785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61975142"],"award-info":[{"award-number":["61975142"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61501468"],"award-info":[{"award-number":["61501468"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100017329","name":"Foundation of Science and Technology on Near-Surface Detection Laboratory","doi-asserted-by":"publisher","award":["6142414180206"],"award-info":[{"award-number":["6142414180206"]}],"id":[{"id":"10.13039\/100017329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Research and Development (R&amp;D) Projects of Shanxi Province","award":["201803D121071"],"award-info":[{"award-number":["201803D121071"]}]},{"name":"Coal-Bed Methane Joint Research Fund of Shanxi Province","award":["2015012005"],"award-info":[{"award-number":["2015012005"]}]},{"name":"Coal-Bed Methane Joint Research Fund of Shanxi Province","award":["2016012011"],"award-info":[{"award-number":["2016012011"]}]},{"name":"Scientific and Technologial Innovation Programs of Higher Education Institutions in Shanxi","award":["2019L0296"],"award-info":[{"award-number":["2019L0296"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In order to enhance the signal-to-noise ratio (SNR) of a distributed optical fiber vibration sensor based on coherent optical time domain reflectometry (COTDR), a high extinction ratio cascade structure of an acousto-optic modulator and semiconductor optical amplifier is applied. The prior time-frequency analysis and least mean square error algorithm are adopted in the COTDR system for amplitude demodulation and phase demodulation, in order to improve the SNR by noise elimination. The experimental results show that the adaptive filter based on the least mean square error algorithm could realize the extraction of a three-order sinusoidal harmonic signal from strong background noise along the optical fiber and the SNR improvement from 10.4 dB to 42.2 dB. The proposed demodulation algorithm is suitable for the detection of vibration signals with characteristic frequencies in the application of acoustic fault diagnosis for electromechanical devices.<\/jats:p>","DOI":"10.3390\/s20072000","type":"journal-article","created":{"date-parts":[[2020,4,2]],"date-time":"2020-04-02T11:57:14Z","timestamp":1585828634000},"page":"2000","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Optical Fiber Vibration Sensor Using Least Mean Square Error Algorithm"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4919-4390","authenticated-orcid":false,"given":"Yu","family":"Wang","sequence":"first","affiliation":[{"name":"College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]},{"given":"Jie","family":"Zou","sequence":"additional","affiliation":[{"name":"College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Yuelin","family":"Xu","sequence":"additional","affiliation":[{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]},{"given":"Yu","family":"Chen","sequence":"additional","affiliation":[{"name":"Science and Technology on Near-Surface Detection Laboratory, Wuxi 214035, China"}]},{"given":"Xin","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Qing","family":"Bai","sequence":"additional","affiliation":[{"name":"College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5737-0374","authenticated-orcid":false,"given":"Baoquan","family":"Jin","sequence":"additional","affiliation":[{"name":"College of Physics and Optoelectronics, Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"},{"name":"State Key Laboratory of Coal and CBM Co-Mining, Jincheng 048000, China"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3307","DOI":"10.1121\/1.4708364","article-title":"Fault diagnosis of railway roller bearing based on vibration analysis and information fusion","volume":"131","author":"Chen","year":"2012","journal-title":"J. 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