{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:16:37Z","timestamp":1760242597997,"version":"build-2065373602"},"reference-count":18,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,7]],"date-time":"2017-12-07T00:00:00Z","timestamp":1512604800000},"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>The spectral linewidth from two cross-correlated fiber Bragg gratings (FBGs) are interrogated and characterized using a delayed self-homodyne method for fiber strain sensing. This approach employs a common higher frequency resolution instead of wavelength. A sensitivity and resolution of 166 MHz\/\u03bc\u03b5 and 50 n\u03b5 were demonstrated from 4 GHz spectral linewidth characterization on the electric spectrum analyzer. A 10 n\u03b5 higher resolution can be expected through random noise analyses when the spectral linewidth from two FBG correlations is reduced to 1 GHz. Moreover, the FBG spectrum is broadened during strain and experimentally shows a 0.44 pm\/\u03bc\u03b5 sensitivity, which is mainly caused by the photo elastic effect from the fiber grating period stretch.<\/jats:p>","DOI":"10.3390\/s17122837","type":"journal-article","created":{"date-parts":[[2017,12,7]],"date-time":"2017-12-07T11:49:10Z","timestamp":1512647350000},"page":"2837","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Two Interrogated FBG Spectral Linewidth for Strain Sensing through Correlation"],"prefix":"10.3390","volume":"17","author":[{"given":"Shih-Hsiang","family":"Hsu","sequence":"first","affiliation":[{"name":"Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kuo-Wei","family":"Chuang","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ci-Syu","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8269-797X","authenticated-orcid":false,"given":"Ching-Yu","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, 250 Wu-Hsing Street, Taipei 11031, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8080-2094","authenticated-orcid":false,"given":"Che-Chang","family":"Chang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, 250 Wu-Hsing Street, Taipei 11031, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1016\/j.yofte.2009.07.004","article-title":"A temperature-insensitive strain sensor using a fiber Bragg grating","volume":"15","author":"Zhuo","year":"2009","journal-title":"Opt. 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