A 2.4-GHz vital-sign sensor for noncontact healthcare monitoring. Issue 8 (23rd May 2016)

• Record Type: Journal Article
• Authors: Wang, Sen; Chen, Yi-Huei; Chang, Ren-Hua
• Is Part Of: Journal of electromagnetic waves and applications. Volume 30:Issue 8(2016)
• Page Start: 1064
• Page End: 1074
• Publication Date: 2016-05-23
• Subjects: Life detection system -- vital-sign signals -- sensors -- noncontact -- injection-locked -- I/Q demodulator -- Health care monitoring; Electromagnetic waves -- Periodicals; Electromagnetic devices -- Periodicals; 621.3
• DOI: 10.1080/09205071.2016.1172517
• Languages: English
• ISSNs: 0920-5071

Abstract

Abstract: This paper presents a 2.4-GHz vital-sign sensor for noncontact healthcare monitoring applications. The sensor consists of one VCO, two circulators, three Wilkinson power dividers, one 90° hybrid, two mixers, and two active band-pass filters. The sensor with the injection-locked VCO and the I/Q demodulator reduces system complexity and avoids the null detection points, respectively. Moreover, the sensor achieves a long sensing distance without the need of a low-noise amplifier or a power amplifier. Under total power consumption of 17.8 mW, experimental results demonstrate that vital-sign signals including respiration and heartbeat can be identified and detected correctly up to 80 cm away from the subject. Moreover, the errors of heartbeats are less than 4.9% compared to a contact device.