{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T02:50:24Z","timestamp":1774407024214,"version":"3.50.1"},"reference-count":28,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,6]],"date-time":"2021-07-06T00:00:00Z","timestamp":1625529600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015816","name":"High Value Manufacturing Catapult","doi-asserted-by":"publisher","award":["1"],"award-info":[{"award-number":["1"]}],"id":[{"id":"10.13039\/501100015816","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["1"],"award-info":[{"award-number":["1"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A method based on equal frequency resampling is proposed to suppress laser nonlinear frequency sweeping for the ultimate spatial resolution in optical frequency domain reflectometry. Estimation inaccuracy of the sweeping frequency distribution caused by the finite sampling rate in the auxiliary interferometer can be efficiently compensated by the equal frequency resampling method. With the sweeping range of 130 nm, a 12.1 \u00b5m spatial resolution is experimentally obtained. In addition, the sampling limitation of the auxiliary interferometer-based correction is discussed. With a 200 m optical path delay in the auxiliary interferometer, a 21.3 \u00b5m spatial resolution is realised at the 191 m fibre end. By employing the proposed resampling and a drawing tower FBG array to enhance the Rayleigh backscattering, a distributed temperature sensing over a 105 m fibre with a sensing resolution of 1 cm is achieved. The measured temperature uncertainty is limited to \u00b10.15 \u00b0C.<\/jats:p>","DOI":"10.3390\/s21144632","type":"journal-article","created":{"date-parts":[[2021,7,6]],"date-time":"2021-07-06T11:36:44Z","timestamp":1625571404000},"page":"4632","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Ultimate Spatial Resolution Realisation in Optical Frequency Domain Reflectometry with Equal Frequency Resampling"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2149-1465","authenticated-orcid":false,"given":"Zhen","family":"Guo","sequence":"first","affiliation":[{"name":"Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5170-7239","authenticated-orcid":false,"given":"Gaoce","family":"Han","sequence":"additional","affiliation":[{"name":"Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK"},{"name":"Electronics and Computer Science (ECS), University of Southampton, Southampton SO17 1BJ, UK"}]},{"given":"Jize","family":"Yan","sequence":"additional","affiliation":[{"name":"Electronics and Computer Science (ECS), University of Southampton, Southampton SO17 1BJ, UK"}]},{"given":"David","family":"Greenwood","sequence":"additional","affiliation":[{"name":"Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK"}]},{"given":"James","family":"Marco","sequence":"additional","affiliation":[{"name":"Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5919-1591","authenticated-orcid":false,"given":"Yifei","family":"Yu","sequence":"additional","affiliation":[{"name":"Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1049\/el:19850402","article-title":"Distributed optical fibre Raman temperature sensor using a semiconductor light source and detector","volume":"21","author":"Dakin","year":"1985","journal-title":"Electron. 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