{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T09:31:57Z","timestamp":1768901517187,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,4,16]],"date-time":"2021-04-16T00:00:00Z","timestamp":1618531200000},"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":["61371198"],"award-info":[{"award-number":["61371198"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Compact high-frequency surface wave radar (HFSWR) plays a critical role in ship surveillance. Due to the wide antenna beam-width and low spatial gain, traditional constant false alarm rate (CFAR) detectors often induce a low detection probability. To solve this problem, a joint detection algorithm based on time-frequency (TF) analysis and the CFAR method is proposed in this paper. After the TF ridge extraction, CFAR detection is performed to test each sample of the ridges, and a binary integration is run to determine whether the entire TF ridge is of a ship. To verify the effectiveness of the proposed algorithm, experimental data collected by the Ocean State Monitoring and Analyzing Radar, type SD (OSMAR-SD) were used, with the ship records from an automatic identification system (AIS) used as ground truth data. The processing results showed that the joint TF-CFAR method outperformed CFAR in detecting non-stationary and weak signals and those within the first-order sea clutters, whereas CFAR outperformed TF-CFAR in identifying multiple signals with similar frequencies. Notably, the intersection of the matched detection sets by TF-CFAR and CFAR alone was not immense, which takes up approximately 68% of the matched number by CFAR and 25% of that by TF-CFAR; however, the number in the union detection sets was much (&gt;30%) greater than the result of either method. Therefore, joint detection with TF-CFAR and CFAR can further increase the detection probability and greatly improve detection performance under complicated situations, such as non-stationarity, low signal-to-noise ratio (SNR), and within the first-order sea clutters.<\/jats:p>","DOI":"10.3390\/rs13081548","type":"journal-article","created":{"date-parts":[[2021,4,19]],"date-time":"2021-04-19T06:35:53Z","timestamp":1618814153000},"page":"1548","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Joint Ship Detection Based on Time-Frequency Domain and CFAR Methods with HF Radar"],"prefix":"10.3390","volume":"13","author":[{"given":"Zhiqing","family":"Yang","sequence":"first","affiliation":[{"name":"The School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Jianjiang","family":"Tang","sequence":"additional","affiliation":[{"name":"East China Sea Forecast Center, State Oceanic Administration, Shanghai 200136, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3680-5903","authenticated-orcid":false,"given":"Hao","family":"Zhou","sequence":"additional","affiliation":[{"name":"The School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"given":"Xinjun","family":"Xu","sequence":"additional","affiliation":[{"name":"Wuhan Hailanruihai Ocean Technology Co. Ltd., Wuhan 430223, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3450-3688","authenticated-orcid":false,"given":"Yingwei","family":"Tian","sequence":"additional","affiliation":[{"name":"The School of Electronic Information, Wuhan University, Wuhan 430072, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7477-4664","authenticated-orcid":false,"given":"Biyang","family":"Wen","sequence":"additional","affiliation":[{"name":"The School of Electronic Information, Wuhan University, Wuhan 430072, China"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"14","DOI":"10.4031\/MTSJ.45.3.2","article-title":"Performance evaluation of SeaSonde high-frequency radar for vessel detection","volume":"45","author":"Roarty","year":"2011","journal-title":"Mar. Technol. Soc. 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