{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T16:23:20Z","timestamp":1775579000583,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,3,1]],"date-time":"2021-03-01T00:00:00Z","timestamp":1614556800000},"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":["61627816 and 61975076"],"award-info":[{"award-number":["61627816 and 61975076"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Key Technology R&amp;D Program of Inner Mongolia Autonomous Region","award":["2019GG374"],"award-info":[{"award-number":["2019GG374"]}]},{"DOI":"10.13039\/501100004826","name":"Beijing Natural Science Foundation","doi-asserted-by":"publisher","award":["4192042"],"award-info":[{"award-number":["4192042"]}],"id":[{"id":"10.13039\/501100004826","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Key Research and Development Program of Jiangsu Province","award":["BE2018047"],"award-info":[{"award-number":["BE2018047"]}]},{"name":"State Key Laboratory of Smart Grid Protection and Control, and University Natural Science Research Project of Jiangsu Province","award":["021314380173"],"award-info":[{"award-number":["021314380173"]}]},{"DOI":"10.13039\/501100004479","name":"Natural Science Foundation of Jiangxi Province","doi-asserted-by":"publisher","award":["19KJB510005"],"award-info":[{"award-number":["19KJB510005"]}],"id":[{"id":"10.13039\/501100004479","id-type":"DOI","asserted-by":"publisher"}]},{"name":"High-Level Training Fund project ofNanjing Xiaozhuang University","award":["2019NXY18"],"award-info":[{"award-number":["2019NXY18"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Phase-sensitive time-domain reflectometry (\u03a6-OTDR) can be used for fully distributed long-distance vibration monitoring. There is a fading phenolmenon in the \u03a6-OTDR, which will cause the signal intensity somewhere to be too low to extract the phase of the signal without distortion. In this paper, the \u03a6-OTDR based on space-division multiplexing (SDM) is proposed to suppress fading and we used multi-core optical fiber (MCF) to realize SDM. While inheriting the previous optimization strategy, we proposed a strategy based on frequency spectral similarity to process multiple independent signals obtained by SDM. And we compared the two methods. Through the experiments, the distortion rate can be reduced from an average level of 9.34% to less than 2% under continuous running of 270 s, which proves that SDM is a reliable technical route to achieve fading suppression. This method can effectively improve the fading suppression capability of the existed commercial systems.<\/jats:p>","DOI":"10.3390\/s21051694","type":"journal-article","created":{"date-parts":[[2021,3,1]],"date-time":"2021-03-01T22:02:20Z","timestamp":1614636140000},"page":"1694","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["A Space-Division Multiplexing Method for Fading Noise Suppression in the \u03a6-OTDR System"],"prefix":"10.3390","volume":"21","author":[{"given":"Yixin","family":"Zhang","sequence":"first","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Jingxiao","family":"Liu","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Fei","family":"Xiong","sequence":"additional","affiliation":[{"name":"Inner Mongolia Electric Power Survey &amp; Design Institute Co., Ltd., Hohhot 010011, China"}]},{"given":"Xuping","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Xiaohong","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"},{"name":"College of Electronic and Optical Engineering &amp; College of Microelectronics, Nanjing University of Posts and Telecommunications, Nanjing 210046, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2252-8135","authenticated-orcid":false,"given":"Zhewen","family":"Ding","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Yunyin","family":"Zheng","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Feng","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Engineering and Applied Sciences, Nanjing University, Gulou District, Nanjing 210093, China"},{"name":"Key Laboratory of Intelligent Optical Sensing and Manipulation, Ministry of Education, Nanjing University, Nanjing 210093, China"}]},{"given":"Mengmeng","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electronic Engineering, Nanjing XiaoZhuang University, Nanjing 211171, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,1]]},"reference":[{"key":"ref_1","first-page":"3243","article-title":"Distributed Vibration Sensor Based on Coherent Detection of Phase-OTDR","volume":"28","author":"Lu","year":"2010","journal-title":"J. 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