{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:22:56Z","timestamp":1785410576969,"version":"3.56.0"},"reference-count":24,"publisher":"Optica Publishing Group","issue":"13","license":[{"start":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T00:00:00Z","timestamp":1782777600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/doi.org\/10.1364\/OA_License_v2#VOR"},{"start":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T00:00:00Z","timestamp":1782777600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/opg.optica.org\/policies\/opg-tdm-policy.json"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62171219"],"award-info":[{"award-number":["62171219"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"},{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62271249"],"award-info":[{"award-number":["62271249"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"},{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Research and Practice Innovation Program of Nanjing University of Aeronautics and Astronautics","award":["xcxjh20250405"],"award-info":[{"award-number":["xcxjh20250405"]}]}],"content-domain":{"domain":["opg.optica.org"],"crossmark-restriction":false},"short-container-title":["Opt. Lett."],"published-print":{"date-parts":[[2026,7,1]]},"abstract":"<jats:p>\n                    We demonstrate an LSTM-assisted optical frequency domain reflectometry (OFDR) method for differential modal group delay (DMGD) characterization of short few-mode fibers. Sparse phase-domain resampling is first applied to compensate for laser sweep nonlinearity with a low sampling rate. Then, the resampled beat signal is extrapolated by an LSTM network to improve the resolution. In a 5-m single-mode fiber, the distance resolution is improved from 4.95\u2009mm to 0.44\u2009mm with a 20.74-GHz sweep bandwidth. The method resolves the overlapped LP\n                    <jats:sub>01<\/jats:sub>\n                    and LP\n                    <jats:sub>11<\/jats:sub>\n                    modal peaks in 1-m and 6-m two-mode fibers, yielding a differential modal group delay of 1.911 ps\/m for the 1-m fiber, in good agreement with the reference values. A 2.2-m four-mode fiber is further tested to demonstrate the applicability of the method. It provides a route for modal characterization of short fibers under a limited sweep bandwidth.\n                  <\/jats:p>","DOI":"10.1364\/ol.604014","type":"journal-article","created":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T11:01:37Z","timestamp":1781607697000},"page":"3761","update-policy":"https:\/\/doi.org\/10.1364\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["LSTM-assisted OFDR for DMGD characterization of a short few-mode fiber"],"prefix":"10.1364","volume":"51","author":[{"given":"Guangkui","family":"Tao","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sihan","family":"Qi","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8817-1847","authenticated-orcid":true,"given":"Qingbo","family":"Liu","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-5521-0972","authenticated-orcid":true,"given":"Xiuyuan","family":"Sun","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhongyang","family":"Xu","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2620-7272","authenticated-orcid":true,"given":"Shilong","family":"Pan","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/01scyh794","id-type":"ROR","asserted-by":"publisher"}]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"285","published-online":{"date-parts":[[2026,6,30]]},"reference":[{"key":"ol-51-13-3761-R1","doi-asserted-by":"publisher","first-page":"4149","DOI":"10.1109\/JLT.2006.883607","type":"journal-article","volume":"24","author":"Froggatt","year":"2006","journal-title":"J. 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All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.","name":"copyright","label":"Copyright"}]}}