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The signals received in \u03a6-OTDR come from the coherent interference of the portion of the fiber illuminated by the light pulse. Its high sensitivity to minute phase changes in the fiber results in a severe reduction in the signal to noise ratio in the intensity trace that demands processing techniques be able to isolate events. For this purpose, this paper proposes a method based on Unsupervised Anomaly Detection techniques which make use of concepts from the field of deep learning and allow the removal of much of the noise from the \u03a6-OTDR signals. The fact that this method is unsupervised means that no human-labeled data are needed for training and only event-free data are used for this purpose. Moreover, this method has been implemented and its performance has been tested with real data showing promising results.<\/jats:p>","DOI":"10.3390\/s22176515","type":"journal-article","created":{"date-parts":[[2022,8,30]],"date-time":"2022-08-30T01:37:55Z","timestamp":1661823475000},"page":"6515","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Unsupervised Anomaly Detection Applied to \u03a6-OTDR"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9407-1381","authenticated-orcid":false,"given":"Antonio","family":"Almud\u00e9var","sequence":"first","affiliation":[{"name":"ViVoLab, Arag\u00f3n Institute for Engineering Research (I3A), University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4094-3826","authenticated-orcid":false,"given":"Pascual","family":"Sevillano","sequence":"additional","affiliation":[{"name":"Applied Physics Department, Arag\u00f3n Institute for Engineering Research (I3A), University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4391-5203","authenticated-orcid":false,"given":"Luis","family":"Vicente","sequence":"additional","affiliation":[{"name":"ViVoLab, Arag\u00f3n Institute for Engineering Research (I3A), University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5898-8777","authenticated-orcid":false,"given":"Javier","family":"Preciado-Garbayo","sequence":"additional","affiliation":[{"name":"Aragon Photonics Labs (APL) and Electronic Engineering and Communications Department, University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3886-7748","authenticated-orcid":false,"given":"Alfonso","family":"Ortega","sequence":"additional","affiliation":[{"name":"ViVoLab, Arag\u00f3n Institute for Engineering Research (I3A), University of Zaragoza, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Agrawal, G. 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