{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T10:15:33Z","timestamp":1788257733596,"version":"build-2803163510"},"reference-count":0,"publisher":"LUMOSCIENCE PUBLISHING LIMITED","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioelectromagn Med"],"abstract":"<jats:p>Background: Continuous cardiac monitoring is important for early cardiovascular risk assessment and long-term health management. Conventional approaches such as electrocardiography, photoplethysmography, seismocardiography, ballistocardiography, and echocardiography provide valuable cardiac information but are limited by body contact, intermittent operation, or user compliance. Millimeter-wave radar offers a contactless electromagnetic sensing approach for detecting subtle body-surface motion related to cardiac activity. This review summarizes recent advances in millimeter-wave radar-based unobtrusive cardiac monitoring, with emphasis on mechanical cardiac waveforms and intra-beat information. Methods: This article is a narrative review of radar-based unobtrusive cardiac monitoring. Representative studies were selected based on their relevance to RF\/millimeter-wave cardiac sensing and were categorized by radar architecture, signal-processing method, waveform representation, monitoring scenario, validation modality, and clinical endpoint. Results: Existing studies show that radar can reliably estimate heart rate and heart rate variability under controlled and home-like conditions. Recent work further demonstrates the potential of radar-derived mechanical cardiograms for intra-beat timing analysis, transformation to standard physiological modalities, rhythm classification, blood pressure waveform estimation, and broader cardiac health assessment. Conclusions: Millimeter-wave radar is a promising technology for continuous, contactless cardiac activity monitoring. Future translation requires robust long-term signal extraction, physiological interpretability, standardized datasets, multimodal validation, and clinically meaningful endpoints.<\/jats:p>","DOI":"10.64187\/bim.2026.v1.i1.004","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T09:38:06Z","timestamp":1788255486000},"source":"Crossref","is-referenced-by-count":0,"title":["Unobtrusive Cardiac Activity Monitoring Using Biomedical Radar: Principles, Applications, and Perspectives"],"prefix":"10.64187","volume":"1","author":[{"given":"Yuchen","family":"Li","sequence":"first","affiliation":[{"name":"State Key Laboratory of Radio Frequency Heterogeneous Integration (Shanghai Jiao Tong University), Shanghai Jiao Tong University, Shanghai, 200240, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Cao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Radio Frequency Heterogeneous Integration (Shanghai Jiao Tong University), Shanghai Jiao Tong University, Shanghai, 200240, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qishan","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Cardiology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 200092, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changzhan","family":"Gu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Radio Frequency Heterogeneous Integration (Shanghai Jiao Tong University), Shanghai Jiao Tong University, Shanghai, 200240, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"53608","published-online":{"date-parts":[[2026,8,31]]},"container-title":["Bioelectromagnetics in Medicine"],"original-title":[],"deposited":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T09:38:07Z","timestamp":1788255487000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.lumoscience.com\/Journals\/BiM\/articles\/bim.2026.v1.i1.004"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,8,31]]},"references-count":0,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,8,31]]}},"URL":"https:\/\/doi.org\/10.64187\/bim.2026.v1.i1.004","relation":{},"subject":[],"published":{"date-parts":[[2026,8,31]]}}}