{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,4]],"date-time":"2026-04-04T18:19:23Z","timestamp":1775326763963,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2022,12,4]],"date-time":"2022-12-04T00:00:00Z","timestamp":1670112000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper presents the first successful drone detection results using a 5G network as a source of illumination in a passive radar system. Furthermore, a novel adaptive strategy for signal integration is shown. The proposed approach is based on the R\u00e9nyi entropy. It allows one to select time frames with a densely allocated downlink channel both in the time and frequency domains. The resource allocation is strongly related to a network load and has a crucial influence on 5G-based passive radar range resolution and detection capabilities. The proposed technique was validated using simulated and real-life signals, confirming the possibility of detecting unmanned aerial vehicles (UAVs) in 5G-network-based passive radars. Moreover, the proposed methodology can be directly used in passive radar systems where the illuminating signal duration and bandwidth are content-dependent, and the radar resolution may vary significantly.<\/jats:p>","DOI":"10.3390\/rs14236146","type":"journal-article","created":{"date-parts":[[2022,12,5]],"date-time":"2022-12-05T05:31:32Z","timestamp":1670218292000},"page":"6146","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["R\u00e9nyi Entropy-Based Adaptive Integration Method for 5G-Based Passive Radar Drone Detection"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2390-6206","authenticated-orcid":false,"given":"Rados\u0142aw","family":"Maksymiuk","sequence":"first","affiliation":[{"name":"Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, 00-665 Warsaw, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5694-1294","authenticated-orcid":false,"given":"Karol","family":"Abratkiewicz","sequence":"additional","affiliation":[{"name":"Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, 00-665 Warsaw, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1607-2298","authenticated-orcid":false,"given":"Piotr","family":"Samczy\u0144ski","sequence":"additional","affiliation":[{"name":"Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, 00-665 Warsaw, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8959-3313","authenticated-orcid":false,"given":"Marek","family":"P\u0142otka","sequence":"additional","affiliation":[{"name":"Institute of Electronic Systems, Faculty of Electronics and Information Technology, Warsaw University of Technology, 00-665 Warsaw, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Filippini, F., Martelli, T., Colone, F., and Cardinali, R. 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