{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:11:52Z","timestamp":1760242312589,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,4,12]],"date-time":"2017-04-12T00:00:00Z","timestamp":1491955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"China NSF Grants","award":["61371169"],"award-info":[{"award-number":["61371169"]}]},{"name":"China Scholarship Council Grants","award":["201606835025"],"award-info":[{"award-number":["201606835025"]}]},{"name":"Yangtze University innovation Foundation","award":["2016-DXCX-05"],"award-info":[{"award-number":["2016-DXCX-05"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A novel scheme is proposed for direction finding with uniform rectangular planar array. First, the characteristics of noncircular signals and Euler\u2019s formula are exploited to construct a new real-valued rectangular array data. Then, the rotational invariance relations for real-valued signal space are depicted in a new way. Finally the real-valued propagator method is utilized to estimate the pairing two-dimensional direction of arrival (2D-DOA). The proposed algorithm provides better angle estimation performance and can discern more sources than the 2D propagator method. At the same time, it has very close angle estimation performance to the noncircular propagator method (NC-PM) with reduced computational complexity.<\/jats:p>","DOI":"10.3390\/s17040840","type":"journal-article","created":{"date-parts":[[2017,4,12]],"date-time":"2017-04-12T10:15:06Z","timestamp":1491992106000},"page":"840","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Fast Noncircular 2D-DOA Estimation for Rectangular Planar Array"],"prefix":"10.3390","volume":"17","author":[{"given":"Lingyun","family":"Xu","sequence":"first","affiliation":[{"name":"College of Science, Nanjing University of Aeronautics &amp; Astronautics, Nanjing 210016, China"},{"name":"Department of Electrical and Computer Engineering, University of Delaware, Newark, DE 19716, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fangqing","family":"Wen","sequence":"additional","affiliation":[{"name":"Electronic and Information School of Yangtze University, Jingzhou 434023, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,4,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1109\/TWC.2003.821215","article-title":"Direction-of-arrival tracking scheme for DS\/CDMA systems: Direction lock loop","volume":"3","author":"Min","year":"2004","journal-title":"IEEE Trans. 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