title: Short-Range Vital Signs Sensing Based on EEMD and CWT Using IR-UWB Radar.
abstract: The radar sensor described realizes healthcare monitoring capable of detecting subject chest-wall movement caused by cardiopulmonary activities and wirelessly estimating the respiration and heartbeat rates of the subject without attaching any devices to the body. Conventional single-tone Doppler radar can only capture Doppler signatures because of a lack of bandwidth information with noncontact sensors. In contrast, we take full advantage of impulse radio ultra-wideband (IR-UWB) radar to achieve low power consumption and convenient portability, with a flexible detection range and desirable accuracy. A noise reduction method based on improved ensemble empirical mode decomposition (EEMD) and a vital sign separation method based on the continuous-wavelet transform (CWT) are proposed jointly to improve the signal-to-noise ratio (SNR) in order to acquire accurate respiration and heartbeat rates. Experimental results illustrate that respiration and heartbeat signals can be extracted accurately under different conditions. This noncontact healthcare sensor system proves the commercial feasibility and considerable accessibility of using compact IR-UWB radar for emerging biomedical applications.
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. xikung_hu@126.com.
authors.forename: Xikun
authors.initials: X
authors.lastname: Hu
authors.affiliation: College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China. tianjin@nudt.edu.cn.
authors.forename: Tian
authors.initials: T
authors.lastname: Jin
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D006801:Humans; D011825:Radar; D012815:Signal Processing, Computer-Assisted; D059629:Signal-To-Noise Ratio; D055986:Vital Signs / Q000502:physiology*; D058067:Wavelet Analysis
keywords: continuous-wavelet transform (CWT); ensemble empirical mode decomposition (EEMD); impulse radio ultra-wideband (IR-UWB) radar; noncontact; short-range; vital signs