{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:59:05Z","timestamp":1760241545941,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2018,4,27]],"date-time":"2018-04-27T00:00:00Z","timestamp":1524787200000},"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":["61471373"],"award-info":[{"award-number":["61471373"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Focusing on the inverse synthetic aperture radar (ISAR) imaging of maneuvering targets, this paper presents a new imaging method which works well when the target\u2019s maneuvering is not too severe. After translational motion compensation, we describe the equivalent rotation of maneuvering targets by two variables\u2014the relative chirp rate of the linear frequency modulated (LFM) signal and the Doppler focus shift. The first variable indicates the target\u2019s motion status, and the second one represents the possible residual error of the translational motion compensation. With them, a modified Fourier transform matrix is constructed and then used for cross-range compression. Consequently, the imaging of maneuvering is converted into a two-dimensional parameter optimization problem in which a stable and clear ISAR image is guaranteed. A gradient descent optimization scheme is employed to obtain the accurate relative chirp rate and Doppler focus shift. Moreover, we designed an efficient and robust initialization process for the gradient descent method, thus, the well-focused ISAR images of maneuvering targets can be achieved adaptively. Human intervention is not needed, and it is quite convenient for practical ISAR imaging systems. Compared to precedent imaging methods, the new method achieves better imaging quality under reasonable computational cost. Simulation results are provided to validate the effectiveness and advantages of the proposed method.<\/jats:p>","DOI":"10.3390\/s18051370","type":"journal-article","created":{"date-parts":[[2018,4,27]],"date-time":"2018-04-27T12:04:50Z","timestamp":1524830690000},"page":"1370","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Adaptive ISAR Imaging of Maneuvering Targets Based on a Modified Fourier Transform"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5665-153X","authenticated-orcid":false,"given":"Binbin","family":"Wang","sequence":"first","affiliation":[{"name":"Science and Technology on Automatic Target Recognition Laboratory, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shiyou","family":"Xu","sequence":"additional","affiliation":[{"name":"Science and Technology on Automatic Target Recognition Laboratory, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenzhen","family":"Wu","sequence":"additional","affiliation":[{"name":"Science and Technology on Automatic Target Recognition Laboratory, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pengjiang","family":"Hu","sequence":"additional","affiliation":[{"name":"Science and Technology on Automatic Target Recognition Laboratory, National University of Defense Technology, Changsha 410073, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zengping","family":"Chen","sequence":"additional","affiliation":[{"name":"Science and Technology on Automatic Target Recognition Laboratory, National University of Defense Technology, Changsha 410073, China"},{"name":"College of Information Engineering, Shenzhen University, Shenzhen 518060, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"486","DOI":"10.1109\/7.670330","article-title":"Joint time\u2013frequency transform for radar range Doppler imaging","volume":"34","author":"Chen","year":"1998","journal-title":"IEEE Trans. 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