{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T22:24:12Z","timestamp":1768688652290,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,11]],"date-time":"2019-12-11T00:00:00Z","timestamp":1576022400000},"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 paper, we propose a fast method for measuring the radar cross section of a complex target at non-normal incidences and Fresnel region antenna-to-target distances. The proposed method relies both on the physical optics approach and on averaging the field distribution over the transmitting and receiving antenna apertures. The ratio between the analytical expression of the radar cross section at far-field and Fresnel region results in a field-zone extrapolation factor. The RCS resulting from the scattering parameters measured at Fresnel region distances is then corrected with that field-zone extrapolation factor. The method is suitable to be used in a perturbed, multipath environment by applying the distance averaging technique, coupling subtraction or time gating. Our technique requires a very simple measuring configuration consisting of two horn antennas and a vector network analyzer. The experimental validation of the proposed technique demonstrates reasonable agreement with simulated radar cross section at non-normal incidence.<\/jats:p>","DOI":"10.3390\/s19245454","type":"journal-article","created":{"date-parts":[[2019,12,12]],"date-time":"2019-12-12T03:20:16Z","timestamp":1576120816000},"page":"5454","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["An UWB Physical Optics Approach for Fresnel-Zone RCS Measurements on a Complex Target at Non-Normal Incidence"],"prefix":"10.3390","volume":"19","author":[{"given":"Ilie Valentin","family":"Mihai","sequence":"first","affiliation":[{"name":"IETR (Institute of Electronics and Telecommunications of Rennes), Univ Rennes, UR1, UMR CNRS 6164, F-35000 Rennes, France"},{"name":"Doctoral School of Electronics, Telecommunications and Information Technology, University Politehnica of Bucharest, Bucharest 061071, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9253-6256","authenticated-orcid":false,"given":"Razvan","family":"Tamas","sequence":"additional","affiliation":[{"name":"Doctoral School of Electronics, Telecommunications and Information Technology, University Politehnica of Bucharest, Bucharest 061071, Romania"},{"name":"Department of Electronics and Telecommunications, Constanta Maritime University, Constanta 900663, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ala","family":"Sharaiha","sequence":"additional","affiliation":[{"name":"IETR (Institute of Electronics and Telecommunications of Rennes), Univ Rennes, UR1, UMR CNRS 6164, F-35000 Rennes, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1109\/CJECE.1993.6592816","article-title":"Radar cross-section of a generic aircraft at HF frequencies","volume":"18","author":"Trueman","year":"1993","journal-title":"Can. 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