{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T02:41:08Z","timestamp":1785465668247,"version":"3.56.0"},"reference-count":30,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2018,11,28]],"date-time":"2018-11-28T00:00:00Z","timestamp":1543363200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this work, a 24-GHz frequency-modulated continuous-wave (FMCW) radar system with two sectoral horn antennas and one transmitting lens antenna for long-range drone detection is presented. The present work demonstrates the detection of a quadcopter-type drone using the implemented radar system up to a distance of 1 km. Moreover, a 3D subspace-based algorithm is proposed for the joint range-azimuth-Doppler estimation of long-range drone detection. The effectiveness of the long-range drone detection is verified with the implemented radar system through a variety of experiments in outdoor environments. This is the first such demonstration for long-range drone detection with a 24-GHz FMCW radar.<\/jats:p>","DOI":"10.3390\/s18124171","type":"journal-article","created":{"date-parts":[[2018,11,28]],"date-time":"2018-11-28T11:43:44Z","timestamp":1543405424000},"page":"4171","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Long-Range Drone Detection of 24 G FMCW Radar with E-plane Sectoral Horn Array"],"prefix":"10.3390","volume":"18","author":[{"given":"Byunggil","family":"Choi","sequence":"first","affiliation":[{"name":"Collaborative Robots Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daegun","family":"Oh","sequence":"additional","affiliation":[{"name":"Collaborative Robots Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu 42988, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sunwoo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jong-Wha","family":"Chong","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7539-6594","authenticated-orcid":false,"given":"Ying-Chun","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Electronic Engineering, Hanyang University, Seoul 04763, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1109\/MCOM.2017.1700452","article-title":"An Amateur Drone Surveillance System Based on the Cognitive Internet of Things","volume":"56","author":"Ding","year":"2018","journal-title":"IEEE Commun. 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