{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,7]],"date-time":"2026-03-07T18:23:15Z","timestamp":1772907795806,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,23]],"date-time":"2019-05-23T00:00:00Z","timestamp":1558569600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004543","name":"China Scholarship Council","doi-asserted-by":"publisher","award":["201606835062"],"award-info":[{"award-number":["201606835062"]}],"id":[{"id":"10.13039\/501100004543","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["6150010825"],"award-info":[{"award-number":["6150010825"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Human identification based on radar signatures of individual heartbeats is crucial in various applications, including user authentication in mobile devices, identification of escaped criminals, etc. Usually, optical systems employed to recognize humans are sensitive to ambient light environments, while radar does not have such a drawback, since it has high penetration and all-weather capability. Meanwhile, since micro-Doppler characteristics from the heart of different people are distinct and not easy to fake, it can be used for identification. In this paper, we employed a deep convolutional neural network (DCNN) and conventional supervised learning methods to realize heartbeat-based identification. First, the heartbeat signals were acquired by a Doppler radar and processed by short-time Fourier transform. Then, predefined features were extracted for the conventional supervised learning algorithms, while time\u2013frequency graphs were directly inputted to the DCNN since the network had its own feature extraction part. It is shown that the DCNN could achieve average accuracy of 98.5% for identifying four people, and higher than 80% when the number of people was less than ten. For conventional supervised learning algorithms when identifying four people, the accuracy of the support vector machine (SVM) was 88.75%, and the accuracy of SVM\u2013Bayes was 91.25%, while naive Bayes had the lowest accuracy of 80.75%.<\/jats:p>","DOI":"10.3390\/rs11101220","type":"journal-article","created":{"date-parts":[[2019,5,24]],"date-time":"2019-05-24T02:22:00Z","timestamp":1558664520000},"page":"1220","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":38,"title":["Heart ID: Human Identification Based on Radar Micro-Doppler Signatures of the Heart Using Deep Learning"],"prefix":"10.3390","volume":"11","author":[{"given":"Peibei","family":"Cao","sequence":"first","affiliation":[{"name":"Key Laboratory of Radar Imaging and Microwave Photonics (Nanjing Univ. Aeronaut. Astronaut.), Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Street, Nanjing 211100, China"}]},{"given":"Weijie","family":"Xia","sequence":"additional","affiliation":[{"name":"Key Laboratory of Radar Imaging and Microwave Photonics (Nanjing Univ. Aeronaut. Astronaut.), Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Street, Nanjing 211100, China"}]},{"given":"Yi","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Radar Imaging and Microwave Photonics (Nanjing Univ. Aeronaut. Astronaut.), Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, 29 Jiangjun Street, Nanjing 211100, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Molchanov, P., Astola, J., and Egiazarian, K. (2012, January 7\u201311). Classification of ground moving radar targets by using joint time-frequency analysis. Proceedings of the IEEE Radar Conference, Atlanta, GA, USA.","DOI":"10.1109\/RADAR.2012.6212166"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Villeval, S., Bilik, I., and G\u00fcrb\u00fcz, S.Z. (2014, January 19\u201323). Application of a 24 GHz FMCW automotive radar for urban target classification. 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