{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T07:15:02Z","timestamp":1760426102980,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,12,6]],"date-time":"2022-12-06T00:00:00Z","timestamp":1670284800000},"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":["62222120","61871391","ZR2021YQ43","2019KJN026"],"award-info":[{"award-number":["62222120","61871391","ZR2021YQ43","2019KJN026"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"publisher","award":["62222120","61871391","ZR2021YQ43","2019KJN026"],"award-info":[{"award-number":["62222120","61871391","ZR2021YQ43","2019KJN026"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Youth Innovation and Technology Support Plan of Universities in Shandong Province","award":["62222120","61871391","ZR2021YQ43","2019KJN026"],"award-info":[{"award-number":["62222120","61871391","ZR2021YQ43","2019KJN026"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In conventional radar signal processing, the cascade of pulse compression (i.e., matched filter) and Radon-Fourier transform (RFT) can extract the estimated scattering coefficient of the target in the range-velocity dimension through long-time coherent integration (i.e., long-time focusing). However, matched filter has problems such as range sidelobes. RFT belongs to a standard time-dimension matched filter, which will cause velocity sidelobes of strong targets. The range-velocity sidelobes caused by matched filter and RFT will mask other weak targets and affect the subsequent signal processing processes such as target detection and tracking. To suppress range-velocity sidelobes and achieve better range-velocity focusing, this paper proposes a time-range adaptive focusing method named APC-IARFT for short, which is based on adaptive pulse compression (APC) and newly proposed iterative adaptive Radon-Fourier transform (IARFT). In the APC-IARFT method, the radar time-range adaptive focusing consists of two steps: range-dimension adaptive focusing and long-time adaptive focusing in the velocity dimension. The APC method can realize range-dimension adaptive focusing and suppress range sidelobes of strong targets. Then, based on the minimum variance distortionless response (MVDR) formulation, the proposed IARFT method iteratively designs time-dimension adaptive filter of each range-velocity grid according to the received signal processed by APC to suppress velocity sidelobes of strong targets and achieve long-time adaptive focusing. Compared with the conventional cascade of matched filter and RFT, the cascade of matched filter and adaptive Radon-Fourier transform (ARFT), the results show that the proposed time-range adaptive focusing method (i.e., APC-IARFT) is competent for a variety of scenarios.<\/jats:p>","DOI":"10.3390\/rs14236182","type":"journal-article","created":{"date-parts":[[2022,12,7]],"date-time":"2022-12-07T04:00:37Z","timestamp":1670385637000},"page":"6182","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Time-Range Adaptive Focusing Method Based on APC and Iterative Adaptive Radon-Fourier Transform"],"prefix":"10.3390","volume":"14","author":[{"given":"Jian","family":"Guan","sequence":"first","affiliation":[{"name":"Marine Target Detection Research Group, Naval Aviation University, Yantai 264001, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3734-1696","authenticated-orcid":false,"given":"Jiazheng","family":"Pei","sequence":"additional","affiliation":[{"name":"Marine Target Detection Research Group, Naval Aviation University, Yantai 264001, China"}]},{"given":"Yong","family":"Huang","sequence":"additional","affiliation":[{"name":"Marine Target Detection Research Group, Naval Aviation University, Yantai 264001, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1040-1655","authenticated-orcid":false,"given":"Xiaolong","family":"Chen","sequence":"additional","affiliation":[{"name":"Marine Target Detection Research Group, Naval Aviation University, Yantai 264001, China"}]},{"given":"Baoxin","family":"Chen","sequence":"additional","affiliation":[{"name":"92337 Troop, PLA, Dalian 116000, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Li, Y., Zeng, T., and Long, T. 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