{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:34:02Z","timestamp":1760243642573,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2013,10,24]],"date-time":"2013-10-24T00:00:00Z","timestamp":1382572800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>High frequency millimeter-wave (MMW) radar-like sensors enable the detection of speech signals. This novel non-acoustic speech detection method has some special advantages not offered by traditional microphones, such as preventing strong-acoustic interference, high directional sensitivity with penetration, and long detection distance. A 94-GHz MMW radar sensor was employed in this study to test its speech acquisition ability. A 34-GHz zero intermediate frequency radar, a 34-GHz superheterodyne radar, and a microphone were also used for comparison purposes. A short-time phase-spectrum-compensation algorithm was used to enhance the detected speech. The results reveal that the 94-GHz radar sensor showed the highest sensitivity and obtained the highest speech quality subjective measurement score. This result suggests that the MMW radar sensor has better performance than a traditional microphone in terms of speech detection for detection distances longer than 1 m. As a substitute for the traditional speech acquisition method, this novel speech acquisition method demonstrates a large potential for many speech related applications.<\/jats:p>","DOI":"10.3390\/s131114248","type":"journal-article","created":{"date-parts":[[2013,10,24]],"date-time":"2013-10-24T12:03:57Z","timestamp":1382616237000},"page":"14248-14260","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A 94-GHz Millimeter-Wave Sensor for Speech Signal Acquisition"],"prefix":"10.3390","volume":"13","author":[{"given":"Sheng","family":"Li","sequence":"first","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Tian","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6421-0232","authenticated-orcid":false,"given":"Guohua","family":"Lu","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 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":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hao","family":"Lv","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiao","family":"Yu","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huijun","family":"Xue","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hua","family":"Zhang","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianqi","family":"Wang","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xijing","family":"Jing","sequence":"additional","affiliation":[{"name":"College of Biomedical Engineering, Fourth Military Medical University, Xi'an 710032, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2013,10,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"17","DOI":"10.2528\/PIER12052207","article-title":"A new Kind of non-acoustic speech acquisition method based on millimeter wave radaro","volume":"130","author":"Li","year":"2012","journal-title":"Prog. 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