{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,14]],"date-time":"2026-01-14T16:55:01Z","timestamp":1768409701317,"version":"3.49.0"},"reference-count":50,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,18]],"date-time":"2024-08-18T00:00:00Z","timestamp":1723939200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Natural Resources of Guangdong Province","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["20220815121807001"],"award-info":[{"award-number":["20220815121807001"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}]},{"DOI":"10.13039\/501100010877","name":"Science, Technology and Innovation Commission of Shenzhen Municipality","doi-asserted-by":"publisher","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}],"id":[{"id":"10.13039\/501100010877","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010877","name":"Science, Technology and Innovation Commission of Shenzhen Municipality","doi-asserted-by":"publisher","award":["20220815121807001"],"award-info":[{"award-number":["20220815121807001"]}],"id":[{"id":"10.13039\/501100010877","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010877","name":"Science, Technology and Innovation Commission of Shenzhen Municipality","doi-asserted-by":"publisher","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}],"id":[{"id":"10.13039\/501100010877","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["20220815121807001"],"award-info":[{"award-number":["20220815121807001"]}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel demodulation scheme for a point-type fiber sensor is designed for salinity concentration monitoring based on a Sagnac interferometer (SI) composed of a tapered polarization-maintaining fiber (TPMF) and optical time stretching technology. The SI, constructed using a PMF with a taper region of 5.92 \u03bcm and an overall length of 30 cm, demonstrated a notable enhancement in the evanescent field, which intensifies the interaction between the light field and external salinity. This enhancement allows for a direct assessment of salinity concentration changes by analyzing the variations in the SI reflection spectra and the experimental results indicate that the sensitivity of the sensor is 0.151 nm\/\u2030. In contrast to traditional fiber optic sensors that depend on spectral demodulation with slower response rates, this work introduces a new approach where the spectral shift is translated to the time domain, utilizing a dispersion compensation fiber (DCF) with the demodulation rate reaching up to 50 MHz. The experimental outcomes reveal that the sensor exhibits a sensitivity of \u22120.15 ns\/\u2030 in the time domain. The designed sensor is anticipated to play a pivotal role in remote, real-time monitoring of ocean salinity.<\/jats:p>","DOI":"10.3390\/s24165339","type":"journal-article","created":{"date-parts":[[2024,8,19]],"date-time":"2024-08-19T06:41:31Z","timestamp":1724049691000},"page":"5339","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Real-Time Optical Fiber Salinity Interrogator Based on Time-Domain Demodulation and TPMF Incorporated Sagnac Interferometer"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1499-2608","authenticated-orcid":false,"given":"Weihao","family":"Lin","sequence":"first","affiliation":[{"name":"The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province, Xiamen Institute of Technology, Xiamen 361021, China"},{"name":"School of Mechanical Electrical and Information Engineering, Xiamen Institute of Technology, Xiamen 361021, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8616-0659","authenticated-orcid":false,"given":"Fang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4535-3366","authenticated-orcid":false,"given":"Jie","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0605-3248","authenticated-orcid":false,"given":"Yuhui","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}]},{"given":"Renan","family":"Xu","sequence":"additional","affiliation":[{"name":"The Higher Educational Key Laboratory for Flexible Manufacturing Equipment Integration of Fujian Province, Xiamen Institute of Technology, Xiamen 361021, China"},{"name":"School of Mechanical Electrical and Information Engineering, Xiamen Institute of Technology, Xiamen 361021, China"}]},{"given":"Xingwei","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1272-1959","authenticated-orcid":false,"given":"Liyang","family":"Shao","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"The Peng Cheng Laboratory, Shenzhen 518005, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R49","DOI":"10.1088\/0957-0233\/14\/5\/201","article-title":"Optical fibre long-period grating sensors: Characteristics and application","volume":"14","author":"James","year":"2003","journal-title":"Meas. 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