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using a two-dimensional (2D) camera. To quickly detect moving targets, an improved optical flow method with detailed modifications in the pyramid, warping, and cost volume network (PWC-Net) is applied. Meanwhile, a clustering algorithm is used to accurately extract the moving target from a noisy background. Then, the target position is estimated using a proposed geometrical pinhole imaging algorithm and cubature Kalman filter (CKF). Specifically, the camera\u2019s installation position and inner parameters are applied to calculate the azimuth, elevation angles, and depth of the target while only using 2D measurements. The proposed geometrical solution has a simple structure and fast computational speed. Different simulations and experiments verify the effectiveness of the proposed method.<\/jats:p>","DOI":"10.3390\/s23104862","type":"journal-article","created":{"date-parts":[[2023,5,18]],"date-time":"2023-05-18T07:35:50Z","timestamp":1684395350000},"page":"4862","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Systematic Solution for Moving-Target Detection and Tracking While Only Using a Monocular Camera"],"prefix":"10.3390","volume":"23","author":[{"given":"Shun","family":"Wang","sequence":"first","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5086-4152","authenticated-orcid":false,"given":"Sheng","family":"Xu","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China"}]},{"given":"Zhihao","family":"Ma","sequence":"additional","affiliation":[{"name":"Shandong Institute of Advanced Technology, CAS, Jinan 250102, China"},{"name":"School of Control Science and Engineering, Shandong University, Jinan 250061, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3159-7175","authenticated-orcid":false,"given":"Dashuai","family":"Wang","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China"},{"name":"School of Microelectronics, Southern University of Science and Technology, Shenzhen 518055, China"}]},{"given":"Weimin","family":"Li","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institute of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, China"},{"name":"Shandong Institute of Advanced Technology, CAS, Jinan 250102, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1196","DOI":"10.1109\/TAES.2017.2667999","article-title":"Optimal sensor placement for 3-D angle-of-arrival target localization","volume":"53","author":"Xu","year":"2017","journal-title":"IEEE Trans. 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