{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T07:08:37Z","timestamp":1772780917910,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2019,4,12]],"date-time":"2019-04-12T00:00:00Z","timestamp":1555027200000},"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 civil engineering quasi-distributed optical fiber sensors are used for reinforced concrete monitoring, precast concrete monitoring, temperature monitoring, strain monitoring and temperature\/strain monitoring. These quasi-distributed sensors necessarily apply some multiplexing technique. However, on many occasions, two or more multiplexing techniques are combined to increase the number of local sensors and then the cost of each sensing point is reduced. In this work, a signal analysis and a new signal demodulation algorithm are reported for a quasi-distributed optic fiber sensor system based on Frequency Division Multiplexing\/Wavelength Division Multiplexing (FDM\/WDM) and low-precision Fabry-P\u00e9rot interferometers. The mathematical analysis and the new algorithm optimize its design, its implementation, improve its functionality and reduce the cost per sensing point. The analysis was corroborated by simulating a quasi-distributed sensor in operation. Theoretical analysis and numerical simulation are in concordance. The optimization considers multiplexing techniques, signal demodulation, physical parameters, system noise, instrumentation, and detection technique. Based on our analysis and previous results reported, the optical sensing system can have more than 4000 local sensors and it has practical applications in civil engineering.<\/jats:p>","DOI":"10.3390\/s19081759","type":"journal-article","created":{"date-parts":[[2019,4,12]],"date-time":"2019-04-12T12:55:04Z","timestamp":1555073704000},"page":"1759","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Signal Analysis, Signal Demodulation and Numerical Simulation of a Quasi-Distributed Optical Fiber Sensor Based on FDM\/WDM Techniques and Fabry-P\u00e9rot Interferometers"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0041-3932","authenticated-orcid":false,"given":"Jos\u00e9 Trinidad","family":"Guillen Bonilla","sequence":"first","affiliation":[{"name":"Departamento de Electr\u00f3nica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C. P. 44430, Guadalajara, Jalisco 44430, Mexico"},{"name":"Departamento de Matem\u00e1ticas, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C.P. 44430, Guadalajara, Jalisco 44430, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"H\u00e9ctor","family":"Guillen Bonilla","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda de Proyectos, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C. P. 44430, Guadalajara, Jalisco 44430, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3648-740X","authenticated-orcid":false,"given":"Ver\u00f3nica Mar\u00eda","family":"Rodr\u00edguez Betancourtt","sequence":"additional","affiliation":[{"name":"Departamento de Qu\u00edmica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C. P. 44430, Guadalajara, Jalisco 44430, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Casillas Zamora","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda de Proyectos, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C. P. 44430, Guadalajara, Jalisco 44430, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4018-672X","authenticated-orcid":false,"given":"Mar\u00eda Eugenia","family":"S\u00e1nchez Morales","sequence":"additional","affiliation":[{"name":"Departamento de Ciencias Tecnol\u00f3gicas, Centro Universitario de la Ci\u00e9nega, Universidad de Guadalajara, Av. Universidad No. 1115, Lindavista, C. P. 47810, Ocotl\u00e1n, Jalisco 47810, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lorenzo","family":"Gildo Ortiz","sequence":"additional","affiliation":[{"name":"Departamento de F\u00edsica, Centro Universitario de Ciencias Exactas e Ingenier\u00edas (C.U.C.E.I.), Universidad de Guadalajara, Blvd. M. Garc\u00eda Barrag\u00e1n 1421, C.P. 44430, Guadalajara, Jalisco 44430, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alex","family":"Guillen Bonilla","sequence":"additional","affiliation":[{"name":"Departamento de Ciencias Computacionales, Centro Universitario de los Valles (CUValles), Universidad de Guadalajara, Ameca Km. 45.5, C.P., Ameca, Jalisco 46600, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1016\/S0924-4247(99)00368-4","article-title":"Fiber optic sensor technology: An overview","volume":"82","author":"Grattan","year":"2000","journal-title":"Sens. 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