{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T16:54:29Z","timestamp":1783961669614,"version":"3.55.0"},"reference-count":52,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2024,8,20]],"date-time":"2024-08-20T00:00:00Z","timestamp":1724112000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education and Science of the Russian Federation","award":["075-15-2022-329"],"award-info":[{"award-number":["075-15-2022-329"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>This paper demonstrates how the processing of Brillouin gain spectra (BGS) by two-dimensional correlation methods improves the accuracy of Brillouin frequency shift (BFS) extraction in distributed fiber optic sensor systems based on the BOTDA\/BOTDR (Brillouin optical time domain analysis\/reflectometry) principles. First, the spectra corresponding to different spatial coordinates of the fiber sensor are resampled. Subsequently, the resampled spectra are aligned by the position of the maximum by shifting in frequency relative to each other. The spectra aligned by the position of the maximum are then averaged, which effectively increases the signal-to-noise ratio (SNR). Finally, the Lorentzian curve fitting (LCF) method is applied to the spectrum with improved characteristics, including a reduced scanning step and an increased SNR. Simulations and experiments have demonstrated that the method is particularly efficacious when the signal-to-noise ratio does not exceed 8 dB and the frequency scanning step is coarser than 4 MHz. This is particularly relevant when designing high-speed sensors, as well as when using non-standard laser sources, such as a self-scanning frequency laser, for distributed fiber-optic sensing.<\/jats:p>","DOI":"10.3390\/a17080365","type":"journal-article","created":{"date-parts":[[2024,8,20]],"date-time":"2024-08-20T01:38:45Z","timestamp":1724117925000},"page":"365","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["An Image Processing-Based Correlation Method for Improving the Characteristics of Brillouin Frequency Shift Extraction in Distributed Fiber Optic Sensors"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7820-7736","authenticated-orcid":false,"given":"Yuri","family":"Konstantinov","sequence":"first","affiliation":[{"name":"Institute of Continuous Media Mechanics of the Ural Branch of the Russian Academy of Sciences\u2014Branch of the Perm Federal Research Center of the Ural Branch of the Russian Academy of Sciences, Academician Korolev St. 1, 614013 Perm, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8588-9889","authenticated-orcid":false,"given":"Anton","family":"Krivosheev","sequence":"additional","affiliation":[{"name":"Institute of Continuous Media Mechanics of the Ural Branch of the Russian Academy of Sciences\u2014Branch of the Perm Federal Research Center of the Ural Branch of the Russian Academy of Sciences, Academician Korolev St. 1, 614013 Perm, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1890-6906","authenticated-orcid":false,"given":"Fedor","family":"Barkov","sequence":"additional","affiliation":[{"name":"Institute of Continuous Media Mechanics of the Ural Branch of the Russian Academy of Sciences\u2014Branch of the Perm Federal Research Center of the Ural Branch of the Russian Academy of Sciences, Academician Korolev St. 1, 614013 Perm, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5068","DOI":"10.1109\/JLT.2024.3384429","article-title":"Distributed Partial Discharge Acoustic Signal Detection and Localization Technology for GIL with Built-in Fiber Optics","volume":"42","author":"Song","year":"2024","journal-title":"J. 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