{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T03:38:26Z","timestamp":1790998706096,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2025,12,7]],"date-time":"2025-12-07T00:00:00Z","timestamp":1765065600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["62301578"],"award-info":[{"award-number":["62301578"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Deep learning for fine-grained radar mode recognition faces a major bottleneck\u2014its heavy reliance on expensively labeled data. To address this, we propose a novel semi-supervised framework that effectively leverages unlabeled data. Through an end-to-end, triple-branch framework that integrates a dual contrastive learning mechanism with tailored strategies for pulse distortions, our model achieves high accuracy with minimal labels. Experimental results on two challenging datasets demonstrate that the proposed framework boosts accuracy by 17% to 34% using only 10% of the labeled data, establishing a new state-of-the-art performance.<\/jats:p>","DOI":"10.3390\/s25247440","type":"journal-article","created":{"date-parts":[[2025,12,8]],"date-time":"2025-12-08T15:30:07Z","timestamp":1765207807000},"page":"7440","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Semi-Supervised Radar Work Mode Recognition Based on Contrastive Learning"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-6023-1772","authenticated-orcid":false,"given":"Peishan","family":"Sun","sequence":"first","affiliation":[{"name":"College of Electronic Countermeasure, National University of Defense Technology, Hefei 230071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1369-7818","authenticated-orcid":false,"given":"Mingyang","family":"Du","sequence":"additional","affiliation":[{"name":"College of Electronic Countermeasure, National University of Defense Technology, Hefei 230071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhihui","family":"Li","sequence":"additional","affiliation":[{"name":"College of Electronic Countermeasure, National University of Defense Technology, Hefei 230071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xuan","family":"Chen","sequence":"additional","affiliation":[{"name":"College of Electronic Countermeasure, National University of Defense Technology, Hefei 230071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9910-0663","authenticated-orcid":false,"given":"Junpeng","family":"Shi","sequence":"additional","affiliation":[{"name":"College of Electronic Countermeasure, National University of Defense Technology, Hefei 230071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,7]]},"reference":[{"key":"ref_1","unstructured":"Schleher, D.C. 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