{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,23]],"date-time":"2026-04-23T14:51:03Z","timestamp":1776955863909,"version":"3.51.4"},"reference-count":65,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,6,26]],"date-time":"2023-06-26T00:00:00Z","timestamp":1687737600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002661","name":"Fonds de la Recherche Scientifique (FNRS)","doi-asserted-by":"publisher","award":["PDR T.0252.19"],"award-info":[{"award-number":["PDR T.0252.19"]}],"id":[{"id":"10.13039\/501100002661","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Federal Public Service of Economy of the Belgian Federal Government","award":["PDR T.0252.19"],"award-info":[{"award-number":["PDR T.0252.19"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Determination of the poloidal magnetic field distribution in tokamaks is of prime importance for the successful operation of tokamaks. In this paper, we propose a polarization-sensitive reflectometry-based optical fiber sensor for measuring the spatial distribution of the poloidal magnetic field in tokamaks. The measurement method exploits the Rayleigh backscattering and Faraday magneto-optic effect in optical fibers. The former is an intrinsic property of optical fibers and enables distributed polarization measurements, while the latter arises in the presence of a magnetic field parallel to the optical fiber axis and rotates the polarization state of the light. When an optical fiber is looped around a toroidal section of the vacuum vessel, the local polarization rotation of the light is proportional to the local poloidal magnetic field in the tokamak. The proposed method is discussed theoretically and experimentally using the results from JET. The obtained magnetic field measurement shows a good agreement with that of the internal discrete coils. A potential solution to recover the magnetic field data from the noise-affected region of the optical measurement is proposed and is demonstrated through simulations using the JET magnetic field configuration.<\/jats:p>","DOI":"10.3390\/s23135923","type":"journal-article","created":{"date-parts":[[2023,6,27]],"date-time":"2023-06-27T02:11:22Z","timestamp":1687831882000},"page":"5923","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Distributed Poloidal Magnetic Field Measurement in Tokamaks Using Polarization-Sensitive Reflectometric Fiber Optic Sensor"],"prefix":"10.3390","volume":"23","author":[{"given":"Prasad","family":"Dandu","sequence":"first","affiliation":[{"name":"Department of Electromagnetism and Telecommunications, University of Mons, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3909-0977","authenticated-orcid":false,"given":"Andrei","family":"Gusarov","sequence":"additional","affiliation":[{"name":"Belgian Nuclear Research Center SCK-CEN, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Willem","family":"Leysen","sequence":"additional","affiliation":[{"name":"Belgian Nuclear Research Center SCK-CEN, 2400 Mol, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4322-1677","authenticated-orcid":false,"given":"Perry","family":"Beaumont","sequence":"additional","affiliation":[{"name":"JET, CCFE, Culham Science Center Abingdon, Oxon OX14 3DB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0494-3650","authenticated-orcid":false,"given":"Marc","family":"Wuilpart","sequence":"additional","affiliation":[{"name":"Department of Electromagnetism and Telecommunications, University of Mons, 7000 Mons, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"name":"JET Contributors","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"647","DOI":"10.1088\/0029-5515\/18\/5\/004","article-title":"Tokamak plasma diagnostics","volume":"18","author":"Equipe","year":"1978","journal-title":"Nucl. 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