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CALT","award":["BK20190397"],"award-info":[{"award-number":["BK20190397"]}]},{"name":"University Joint Innovation Fund Project of CALT","award":["201920052001"],"award-info":[{"award-number":["201920052001"]}]},{"name":"University Joint Innovation Fund Project of CALT","award":["NE2020004"],"award-info":[{"award-number":["NE2020004"]}]},{"name":"University Joint Innovation Fund Project of CALT","award":["CALT2021-11"],"award-info":[{"award-number":["CALT2021-11"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["61901213"],"award-info":[{"award-number":["61901213"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["2020B1515120060"],"award-info":[{"award-number":["2020B1515120060"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["BK20190397"],"award-info":[{"award-number":["BK20190397"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["201920052001"],"award-info":[{"award-number":["201920052001"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["NE2020004"],"award-info":[{"award-number":["NE2020004"]}]},{"name":"Science and Technology Innovation Project for Overseas Researchers in Nanjing","award":["CALT2021-11"],"award-info":[{"award-number":["CALT2021-11"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>It is known that synthetic aperture radar (SAR) images obtained by typical matched filtering (MF)-based algorithms always suffer from serious noise, sidelobes and clutter. However, the improvement in image quality means that the complexity of SAR systems will increase, which affects the applications of SAR images. The introduction of sparse signal processing technologies into SAR imaging proposes a new way to solve this problem. Sparse SAR images obtained by sparse recovery algorithms show better image performance than typical complex SAR images with lower sidelobes and higher signal-to-noise ratios (SNR). As the most widely applied fields of SAR images, target detection and target classification rely on SAR images with high quality. Therefore, in this paper, a target detection framework based on sparse images recovered by complex approximate message passing (CAMP) algorithm and a novel classification network via sparse images reconstructed by the new iterative soft thresholding (BiIST) algorithm are proposed. Experimental results show that sparse SAR images have better performance whether for target classification or for target detection than the images recovered by MF-based algorithms, which validates the huge application potentials of sparse images.<\/jats:p>","DOI":"10.3390\/rs14174366","type":"journal-article","created":{"date-parts":[[2022,9,8]],"date-time":"2022-09-08T04:18:32Z","timestamp":1662610712000},"page":"4366","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Complex-Valued Sparse SAR-Image-Based Target Detection and Classification"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1918-5052","authenticated-orcid":false,"given":"Chen","family":"Song","sequence":"first","affiliation":[{"name":"National Key Laboratory of Microwave Imaging Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiarui","family":"Deng","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Eduction, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zehao","family":"Liu","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Eduction, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7385-6171","authenticated-orcid":false,"given":"Bingnan","family":"Wang","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Microwave Imaging Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yirong","family":"Wu","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Microwave Imaging Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9357-8412","authenticated-orcid":false,"given":"Hui","family":"Bi","sequence":"additional","affiliation":[{"name":"The Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Eduction, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,2]]},"reference":[{"key":"ref_1","unstructured":"Curlander, J.C., and Mcdonough, R.N. 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