{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T03:17:29Z","timestamp":1770347849112,"version":"3.49.0"},"reference-count":42,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2021,10,26]],"date-time":"2021-10-26T00:00:00Z","timestamp":1635206400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"State task","award":["."],"award-info":[{"award-number":["."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a theoretical and experimental study in which we increased the sensitivity of a phase-sensitive optical time-domain reflectometer (phi-OTDR). This was achieved by constructing coils in the sensor cable, which increased the total amplitude of the impact on the fiber. We demonstrate this theoretically using the example of a phase-sensitive reflectometer model and practically in testing grounds with a buried nearby conventional sensor and a sensor with coils. The sensitivity increased 2.2 times. We detected 95% of events when using coils, versus 20% when using a straight cable. The suggested method does not require any modifications to the device.<\/jats:p>","DOI":"10.3390\/s21217077","type":"journal-article","created":{"date-parts":[[2021,10,26]],"date-time":"2021-10-26T23:54:33Z","timestamp":1635292473000},"page":"7077","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Sensitivity Improvement of Phi-OTDR by Fiber Cable Coils"],"prefix":"10.3390","volume":"21","author":[{"given":"Konstantin V.","family":"Stepanov","sequence":"first","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6772-1572","authenticated-orcid":false,"given":"Andrey A.","family":"Zhirnov","sequence":"additional","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"},{"name":"Kotelnikov Institute of Radioengineering and Electronics of RAS, Mokhovaya 11-7, 125009 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kirill I.","family":"Koshelev","sequence":"additional","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0302-5687","authenticated-orcid":false,"given":"Anton O.","family":"Chernutsky","sequence":"additional","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Roman I.","family":"Khan","sequence":"additional","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexey B.","family":"Pnev","sequence":"additional","affiliation":[{"name":"Bauman Moscow State Technical University, 2-nd Baumanskaya 5-1, 105005 Moscow, Russia"},{"name":"Kotelnikov Institute of Radioengineering and Electronics of RAS, Mokhovaya 11-7, 125009 Moscow, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Baldwin, C.S. 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