{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:15:17Z","timestamp":1760242517212,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,9,30]],"date-time":"2017-09-30T00:00:00Z","timestamp":1506729600000},"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>Ultra-wide band (UWB) radar for short-range human target detection is widely used to find and locate survivors in some rescue missions after a disaster. The results of the application of bistatic UWB radar for detecting multi-stationary human targets have shown that human targets close to the radar antennas are very often visible, while those farther from radar antennas are detected with less reliability. In this paper, on account of the significant difference of frequency content between the echo signal of the human target and that of noise in the shadowing region, an algorithm based on wavelet entropy is proposed to detect multiple targets. Our findings indicate that the entropy value of human targets was much lower than that of noise. Compared with the method of adaptive filtering and the energy spectrum, wavelet entropy can accurately detect the person farther from the radar antennas, and it can be employed as a useful tool in detecting multiple targets by bistatic UWB radar.<\/jats:p>","DOI":"10.3390\/s17102255","type":"journal-article","created":{"date-parts":[[2017,10,2]],"date-time":"2017-10-02T13:10:05Z","timestamp":1506949805000},"page":"2255","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["An Algorithm Based Wavelet Entropy for Shadowing Effect of Human Detection Using Ultra-Wideband Bio-Radar"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5598-2000","authenticated-orcid":false,"given":"Huijun","family":"Xue","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Miao","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Center for Disease Control and Prevention of Guangzhou Military Region, Guangzhou 510507, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fulai","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fugui","family":"Qi","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3189-6482","authenticated-orcid":false,"given":"Fuming","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering, Lanzhou General Hospital of Lanzhou Military Area Command of PLA, Lanzhou 730050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Lv","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianqi","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8540-1254","authenticated-orcid":false,"given":"Yang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Biomedical Engineering, Fourth Military Medical University, Xi\u2019an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1109\/TBME.1986.325760","article-title":"An X-banc microwave life-detection system","volume":"33","author":"Chen","year":"1986","journal-title":"IEEE Trans. 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