{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,4]],"date-time":"2026-07-04T17:09:22Z","timestamp":1783184962773,"version":"3.54.6"},"reference-count":31,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2024,4,27]],"date-time":"2024-04-27T00:00:00Z","timestamp":1714176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Science Foundation of China (NSF)","award":["62371227"],"award-info":[{"award-number":["62371227"]}]},{"name":"National Science Foundation of China (NSF)","award":["62371225"],"award-info":[{"award-number":["62371225"]}]},{"name":"National Science Foundation of China (NSF)","award":["61601167"],"award-info":[{"award-number":["61601167"]}]},{"name":"National Science Foundation of China (NSF)","award":["kfjj20170412"],"award-info":[{"award-number":["kfjj20170412"]}]},{"name":"National Science Foundation of China (NSF)","award":["KF20181915"],"award-info":[{"award-number":["KF20181915"]}]},{"name":"Nanjing University of Aeronautics and Astronautics (NUAA)","award":["62371227"],"award-info":[{"award-number":["62371227"]}]},{"name":"Nanjing University of Aeronautics and Astronautics (NUAA)","award":["62371225"],"award-info":[{"award-number":["62371225"]}]},{"name":"Nanjing University of Aeronautics and Astronautics (NUAA)","award":["61601167"],"award-info":[{"award-number":["61601167"]}]},{"name":"Nanjing University of Aeronautics and Astronautics (NUAA)","award":["kfjj20170412"],"award-info":[{"award-number":["kfjj20170412"]}]},{"name":"Nanjing University of Aeronautics and Astronautics (NUAA)","award":["KF20181915"],"award-info":[{"award-number":["KF20181915"]}]},{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space NUAA, Ministry of Industry and Information Technology","award":["62371227"],"award-info":[{"award-number":["62371227"]}]},{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space NUAA, Ministry of Industry and Information Technology","award":["62371225"],"award-info":[{"award-number":["62371225"]}]},{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space NUAA, Ministry of Industry and Information Technology","award":["61601167"],"award-info":[{"award-number":["61601167"]}]},{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space NUAA, Ministry of Industry and Information Technology","award":["kfjj20170412"],"award-info":[{"award-number":["kfjj20170412"]}]},{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space NUAA, Ministry of Industry and Information Technology","award":["KF20181915"],"award-info":[{"award-number":["KF20181915"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a new technique for estimating the two-dimensional direction of departure (2D-DOD) and direction of arrival (2D-DOA) in bistatic uniform planar array Multiple-Input Multiple-Output (MIMO) radar systems. The method is based on the reduced-dimension (RD) MUSIC algorithm, aiming to achieve improved precision and computational efficiency. Primarily, this pioneering approach efficiently transforms the four-dimensional (4D) estimation problem into two-dimensional (2D) searches, thus reducing the computational complexity typically associated with conventional MUSIC algorithms. Then, exploits the spatial diversity of array response vectors to construct a 4D spatial spectrum function, which is crucial in resolving the complex angular parameters of multiple simultaneous targets. Finally, the objective is to simplify the spatial spectrum to a 2D search within a 4D measurement space to achieve an optimal balance between efficiency and accuracy. Simulation results validate the effectiveness of our proposed algorithm compared to several existing approaches, demonstrating its robustness in accurately estimating 2D-DOD and 2D-DOA across various scenarios. The proposed technique shows significant computational savings and high-resolution estimations and maintains high precision, setting a new benchmark for future explorations in the field.<\/jats:p>","DOI":"10.3390\/s24092801","type":"journal-article","created":{"date-parts":[[2024,4,29]],"date-time":"2024-04-29T08:49:24Z","timestamp":1714380564000},"page":"2801","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Low-Complexity 2D-DOD and 2D-DOA Estimation in Bistatic MIMO Radar Systems: A Reduced-Dimension MUSIC Algorithm Approach"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4280-5766","authenticated-orcid":false,"given":"Mushtaq","family":"Ahmad","sequence":"first","affiliation":[{"name":"College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1464-1987","authenticated-orcid":false,"given":"Xiaofei","family":"Zhang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space, Nanjing University of Aeronautics and Astronautics, Ministry of Industry and Information Technology, Nanjing 211106, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6281-5887","authenticated-orcid":false,"given":"Xin","family":"Lai","sequence":"additional","affiliation":[{"name":"College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5400-9831","authenticated-orcid":false,"given":"Farman","family":"Ali","sequence":"additional","affiliation":[{"name":"College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1004-386X","authenticated-orcid":false,"given":"Xinlei","family":"Shi","sequence":"additional","affiliation":[{"name":"College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,4,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.1016\/j.sigpro.2015.04.014","article-title":"Joint diagonalization based 2D-DOD and 2D-DOA estimation for bistatic MIMO radar","volume":"116","author":"Xia","year":"2015","journal-title":"Signal Process."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"163119","DOI":"10.1109\/ACCESS.2019.2951892","article-title":"Target localization in bistatic EMVS-MIMO radar using tensor subspace method","volume":"7","author":"Mao","year":"2019","journal-title":"IEEE Access"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1507","DOI":"10.1109\/LSP.2023.3324585","article-title":"Joint 2D-DOD and 2D-DOA estimation in bistatic MIMO radar via tensor ring decomposition","volume":"30","author":"Xie","year":"2023","journal-title":"IEEE Signal Process. 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