{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:42:41Z","timestamp":1760402561866,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2020,1,24]],"date-time":"2020-01-24T00:00:00Z","timestamp":1579824000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, a dual refractive index and temperature sensor based on an interferometric system and on the empirical mode decomposition (EMD) algorithm is presented. Here, it is shown that the EMD provides a comprehensive way to analyze and decompose complex reflection spectra produced by an interferometric filter build at the tip of an optical fiber. By applying the EMD algorithm, the spectrum can be decomposed into a set of intrinsic mode functions (IMF) from which the temperature and the refractive index can be easily extracted. Moreover, the proposed methodology provides a detailed insight of the behavior of this type of interferometric sensors and allows widening of the dynamic measurement ranges of both variables. Here, for proof of principle purposes, a filter based on a stack of three layers (two of them were thermo-sensitive) was fabricated. Finally, it is shown that the proposed methodology can decompose the experimental measured spectra and to determine the refractive index and the temperature, supporting the mathematical model.<\/jats:p>","DOI":"10.3390\/s20030664","type":"journal-article","created":{"date-parts":[[2020,1,24]],"date-time":"2020-01-24T11:01:00Z","timestamp":1579863660000},"page":"664","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Optical Fiber FP Sensor for Simultaneous Measurement of Refractive Index and Temperature Based on the Empirical Mode Decomposition Algorithm"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5480-3384","authenticated-orcid":false,"given":"Everardo","family":"Vargas-Rodriguez","sequence":"first","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Campus Irapuato-Salamanca, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Guanajuato C.P. 38940, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5545-6852","authenticated-orcid":false,"given":"Ana Dinora","family":"Guzman-Chavez","sequence":"additional","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Campus Irapuato-Salamanca, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Guanajuato C.P. 38940, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4454-0845","authenticated-orcid":false,"given":"Roberto","family":"Baeza-Serrato","sequence":"additional","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Campus Irapuato-Salamanca, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Guanajuato C.P. 38940, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1947-9595","authenticated-orcid":false,"given":"Mario Alberto","family":"Garcia-Ramirez","sequence":"additional","affiliation":[{"name":"Centro Universitario de Ciencias Exactas e Ingenier\u00edas, Universidad de Guadalajara, Blvd. Marcelino Garcia Barragan 1421, Guadalajara, Jalisco C.P. 44430, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1900094","DOI":"10.1002\/lpor.201900094","article-title":"A Comprehensive Review of Optical Fiber Refractometers: Toward a Standard Comparative Criterion","volume":"13","author":"Urrutia","year":"2019","journal-title":"Laser Photonics Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10479","DOI":"10.1364\/AO.54.010479","article-title":"Fabry-Perot based strain insensitive photonic crystal fiber modal interferometer for inline sensing of refractive index and temperature","volume":"54","author":"Dash","year":"2015","journal-title":"Appl. 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