{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,24]],"date-time":"2026-03-24T05:55:15Z","timestamp":1774331715417,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,15]],"date-time":"2020-11-15T00:00:00Z","timestamp":1605398400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002855","name":"Ministry of Science and Technology of the People's Republic of China","doi-asserted-by":"publisher","award":["2018YFC0809500"],"award-info":[{"award-number":["2018YFC0809500"]}],"id":[{"id":"10.13039\/501100002855","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004536","name":"Southwest Jiaotong University","doi-asserted-by":"publisher","award":["A0920502051826, YH199911041801, & YX1199912371901"],"award-info":[{"award-number":["A0920502051826, YH199911041801, & YX1199912371901"]}],"id":[{"id":"10.13039\/501100004536","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002338","name":"Ministry of Education of the People's Republic of China","doi-asserted-by":"publisher","award":["2682018CX20"],"award-info":[{"award-number":["2682018CX20"]}],"id":[{"id":"10.13039\/501100002338","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Millimeter wave (MMW) technology is expanding rapidly into security screening for dangerous items concealed under clothing. It uses safe non-ionizing radiation and penetrates clothing well. We present a new planar system at Ka band for the three-dimensional simultaneous imaging of both sides of an inspected person where the images are produced in real time by a recently proposed generalized holographic reconstruction algorithm. Low-cost linear frequency modulation (LFM) radar technology is used along with a simple but efficient method for system calibration. Experimental characterization of the spatial resolution and the sensitivity of the system prototype has been carried out. It is established that the achieved spatial resolution is 6 mm or better if the item is not obscured by clothing and it may deteriorate to 7 mm depending on the clothing hiding the item. The spatial sensitivity is confirmed to be at least 2 mm.<\/jats:p>","DOI":"10.3390\/s20226527","type":"journal-article","created":{"date-parts":[[2020,11,16]],"date-time":"2020-11-16T21:48:52Z","timestamp":1605563332000},"page":"6527","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Ka Band Holographic Imaging System Based on Linear Frequency Modulation Radar"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0802-503X","authenticated-orcid":false,"given":"Yang","family":"Meng","sequence":"first","affiliation":[{"name":"School of Physics, University of Electronic Science and Technology of China, Chengdu 611731, China"}]},{"given":"Chuan","family":"Lin","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Southwest Jiaotong University, Chengdu 611756, China"}]},{"given":"Jiefeng","family":"Zang","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering, Southwest Jiaotong University, Chengdu 611756, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7979-3186","authenticated-orcid":false,"given":"Anyong","family":"Qing","sequence":"additional","affiliation":[{"name":"School of Physics, University of Electronic Science and Technology of China, Chengdu 611731, China"},{"name":"School of Electrical Engineering, Southwest Jiaotong University, Chengdu 611756, China"}]},{"given":"Natalia K.","family":"Nikolova","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON L8S 4K1, Canada"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1111\/0162-895X.00295","article-title":"The consequences of terrorism-disentangling the effects of personal and national threat","volume":"23","author":"Huddy","year":"2002","journal-title":"Political Psychol."},{"key":"ref_2","unstructured":"(2020, July 01). 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