{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T17:14:17Z","timestamp":1760116457797,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2024,11,7]],"date-time":"2024-11-07T00:00:00Z","timestamp":1730937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2023YFF0719403","2208085MF160","2023ZNAJK01"],"award-info":[{"award-number":["2023YFF0719403","2208085MF160","2023ZNAJK01"]}]},{"name":"Anhui Provincial Natural Science Foundation under Grant","award":["2023YFF0719403","2208085MF160","2023ZNAJK01"],"award-info":[{"award-number":["2023YFF0719403","2208085MF160","2023ZNAJK01"]}]},{"name":"Open Project of The Anhui Intelligent Security Technology Engineering Research Center (Hefei Normal University)","award":["2023YFF0719403","2208085MF160","2023ZNAJK01"],"award-info":[{"award-number":["2023YFF0719403","2208085MF160","2023ZNAJK01"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In this paper, we propose a novel approach for circular Multiple-Input Multiple-Output (MIMO) array imaging, termed the Partial Equivalent Method (PEM), aimed at sidelobe suppression. In our method, the imaging process of the circular MIMO array is initially decomposed into bistatic circular synthetic aperture radar (BCSAR) components with different bistatic angles. Components with larger bistatic angles produce equivalent channels whose wavenumber spectra are concentrated near zero frequency, leading to significant broadening of the main lobe in the corresponding point spread function (PSF). In traditional MIMO imaging, each transmit\u2013receive antenna pair is considered an equivalent channel, and all these channels are utilized for imaging. However, components with large bistatic angles, when integrated into the MIMO imaging output, result in increased sidelobe levels. To address this issue, we employ the PEM to restrict the range of equivalent channels. This method selectively retains effective channels generated by components with specific bistatic angles, effectively mitigating the adverse effects of BCSAR components with larger bistatic angles. Through point target simulations, electromagnetic simulations, and practical experiments, we demonstrate that the PEM significantly reduces sidelobes and enhances image quality in circular MIMO array imaging.<\/jats:p>","DOI":"10.3390\/rs16224157","type":"journal-article","created":{"date-parts":[[2024,11,7]],"date-time":"2024-11-07T12:12:13Z","timestamp":1730981533000},"page":"4157","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimizing Circular MIMO Array Imaging Using Partial Equivalent Method for Sidelobe Suppression"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0008-3105-1974","authenticated-orcid":false,"given":"Yiming","family":"Dai","sequence":"first","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"given":"Zhikun","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0632-0008","authenticated-orcid":false,"given":"Hong","family":"Ye","sequence":"additional","affiliation":[{"name":"School of Internet, Anhui University, Hefei 230039, China"}]},{"given":"Xu","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0553-7571","authenticated-orcid":false,"given":"Jun","family":"Yang","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9687-6856","authenticated-orcid":false,"given":"Guangsheng","family":"Deng","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0926-3598","authenticated-orcid":false,"given":"Ying","family":"Li","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7567-0100","authenticated-orcid":false,"given":"Zhiping","family":"Yin","sequence":"additional","affiliation":[{"name":"School of Instrument Science and Opto-Electronics Engineering, Hefei University of Technology, Hefei 230009, China"},{"name":"National Engineering Laboratory of Special Display Technology, Academy of Opto-Electric Technology, Hefei University of Technology, Hefei 230009, China"}]}],"member":"1968","published-online":{"date-parts":[[2024,11,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Brancaccio, A., and Palladino, S. 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