{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T14:21:13Z","timestamp":1766067673805,"version":"build-2065373602"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T00:00:00Z","timestamp":1677196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Second Century Fund (C2F), Chulalongkorn University, Bangkok, Thailand"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Multiple-input multiple-output (MIMO) radars enable better estimation accuracy with improved resolution in contrast to traditional radar systems; thus, this field has attracted attention in recent years from researchers, funding agencies, and practitioners. The objective of this work is to estimate the direction of arrival of targets for co-located MIMO radars by proposing a novel approach called flower pollination. This approach is simple in concept, easy to implement and has the capability of solving complex optimization problems. The received data from the far field located targets are initially passed through the matched filter to enhance the signal-to-noise ratio, and then the fitness function is optimized by incorporating the concept of virtual or extended array manifold vectors of the system. The proposed approach outperforms other algorithms mentioned in the literature by utilizing statistical tools for fitness, root mean square error, cumulative distribution function, histograms, and box plots.<\/jats:p>","DOI":"10.3390\/s23052550","type":"journal-article","created":{"date-parts":[[2023,2,27]],"date-time":"2023-02-27T02:10:46Z","timestamp":1677463846000},"page":"2550","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A Novel Approach for Direction of Arrival Estimation in Co-Located MIMO Radars by Exploiting Extended Array Manifold Vectors"],"prefix":"10.3390","volume":"23","author":[{"given":"Sadiq","family":"Akbar","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad","family":"Sohail","sequence":"additional","affiliation":[{"name":"School of Information Science and Technology, University of Science and Technology of China (USTC), Hefei 230026, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fawad","family":"Zaman","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, COMSATS University Islamabad, Islamabad 44000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Muhammad Abdul Rehman","family":"Khan","sequence":"additional","affiliation":[{"name":"Department of Avionics Engineering, Institute of Space Technology Islamabad, Islamabad 44000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nopdanai","family":"Ajavakom","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6518-0992","authenticated-orcid":false,"given":"Gridsada","family":"Phanomchoeng","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Micro\/Nano Electromechanical Integrated Device Research Unit, Faculty of Engineering, Chulalongkorn University, Bangkok 10330, Thailand"},{"name":"Applied Medical Virology Research Unit, Chulalongkorn University, Bangkok 10330, Thailand"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ravi, K.C., and Kumar, J. 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