{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T04:18:45Z","timestamp":1776399525571,"version":"3.51.2"},"reference-count":188,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,4,18]],"date-time":"2019-04-18T00:00:00Z","timestamp":1555545600000},"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":["61805167"],"award-info":[{"award-number":["61805167"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Coal-Bed Methane Joint Research Fund of Shanxi Province, China","award":["2015012005 and 2016012011"],"award-info":[{"award-number":["2015012005 and 2016012011"]}]},{"name":"Social Development Project of Shanxi Province Key Research Plan","award":["201703D321034"],"award-info":[{"award-number":["201703D321034"]}]},{"name":"Key Research and Development (R&amp;D) Projects of Shanxi Province","award":["201803D121071"],"award-info":[{"award-number":["201803D121071"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In the past two decades Brillouin-based sensors have emerged as a newly-developed optical fiber sensing technology for distributed temperature and strain measurements. Among these, the Brillouin optical time domain reflectometer (BOTDR) has attracted more and more research attention, because of its exclusive advantages, including single-end access, simple system architecture, easy implementation and widespread field applications. It is realized mainly by injecting optical pulses into the fiber and detecting the Brillouin frequency shift (BFS), which is linearly related to the change of ambient temperature and axial strain of the sensing fiber. In this paper, the authors provide a review of new progress on performance improvement and applications of BOTDR in the last decade. Firstly, the recent advances in improving the performance of BOTDRs are summarized, such as spatial resolution, signal-to-noise ratio and measurement accuracy, measurement speed, cross sensitivity and other properties. Moreover, novel-type optical fibers bring new characteristics to optic fiber sensors, hence we introduce the different Brillouin sensing features of special fibers, mainly covering the plastic optical fiber, photonic crystal fiber, few-mode fiber and other special fibers. Additionally, we present a brief overview of BOTDR application scenarios in many industrial fields and intelligent perception, including structural health monitoring of large-range infrastructure, geological disaster prewarning and other applications. To conclude, we discuss several challenges and prospects in the future development of BOTDRs.<\/jats:p>","DOI":"10.3390\/s19081862","type":"journal-article","created":{"date-parts":[[2019,4,18]],"date-time":"2019-04-18T11:58:21Z","timestamp":1555588701000},"page":"1862","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":138,"title":["Recent Advances in Brillouin Optical Time Domain Reflectometry"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1933-3767","authenticated-orcid":false,"given":"Qing","family":"Bai","sequence":"first","affiliation":[{"name":"Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Qinglin","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Dong","family":"Wang","sequence":"additional","affiliation":[{"name":"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\/0000-0002-4919-4390","authenticated-orcid":false,"given":"Yu","family":"Wang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Yan","family":"Gao","sequence":"additional","affiliation":[{"name":"Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Hongjuan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Advanced Transducers and Intelligent Control Systems (Ministry of Education and Shanxi Province), Taiyuan University of Technology, Taiyuan 030024, China"}]},{"given":"Mingjiang","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Physics and Optoelectronics, 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":"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, Shanxi Jincheng Anthracite Mine Group Co., Ltd., Jincheng 048000, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"423","DOI":"10.1063\/1.1653255","article-title":"Radiation losses in glass optical waveguides","volume":"17","author":"Kapron","year":"1970","journal-title":"Appl. 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