Short-Range Vital Signs Sensing Based on EEMD and CWT Using IR-UWB Radar

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.

[1]  R.J. Fontana,et al.  Recent system applications of short-pulse ultra-wideband (UWB) technology , 2004, IEEE Transactions on Microwave Theory and Techniques.

[2]  Bharat Gupta,et al.  FM-UWB for Communications and Radar in Medical Applications , 2009, Wirel. Pers. Commun..

[3]  Li Sun,et al.  Through-the-wall human respiration detection using impulse ultra-wide-band radar , 2016, 2016 IEEE Topical Conference on Biomedical Wireless Technologies, Networks, and Sensing Systems (BioWireleSS).

[4]  G. Ramachandran,et al.  Reconstruction of sequential cardiac in-plane displacement patterns on the chest wall by laser speckle interferometry , 1991, IEEE Transactions on Biomedical Engineering.

[5]  Changzhi Li,et al.  Random Body Movement Cancellation in Doppler Radar Vital Sign Detection , 2008, IEEE Transactions on Microwave Theory and Techniques.

[6]  Namdar Saniei,et al.  A new wavelet based algorithm for estimating respiratory motion rate using UWB radar , 2009, 2009 International Conference on Biomedical and Pharmaceutical Engineering.

[7]  Cornel Ioana,et al.  Short-Range Wideband FMCW Radar for Millimetric Displacement Measurements , 2014, IEEE Transactions on Geoscience and Remote Sensing.

[8]  Hsuan-Jung Su,et al.  Range resolution improvement for FMCW radars , 2008, 2008 European Radar Conference.

[9]  Yang Hao,et al.  Detecting Vital Signs with Wearable Wireless Sensors , 2010, Sensors.

[10]  L.P. Ligthart,et al.  UWB Radar for Human Being Detection , 2005, IEEE Aerospace and Electronic Systems Magazine.

[11]  Jerry L. Eaves,et al.  Introduction to Radar , 1987 .

[12]  Yazhou Wang,et al.  Reconfigurable ultra-wide band see-through-wall imaging radar system , 2009, 2009 IEEE Antennas and Propagation Society International Symposium.

[13]  Sixin Liu,et al.  Remote Detection of Human Vital Sign With Stepped-Frequency Continuous Wave Radar , 2014, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing.

[14]  Carlos G. Bilich.  Bio-Medical Sensing using Ultra Wideband Communications and Radar Technology: A Feasibility Study , 2006, 2006 Pervasive Health Conference and Workshops.

[15]  E. M. Staderini,et al.  UWB radars in medicine , 2002 .

[16]  Changzhi Li,et al.  Development of Non-contact Physiological Motion Sensor on CMOS Chip and Its Potential Applications , 2007, 2007 7th International Conference on ASIC.

[17]  S. Venkatesh,et al.  Implementation and analysis of respiration-rate estimation using impulse-based UWB , 2005, MILCOM 2005 - 2005 IEEE Military Communications Conference.

[18]  Hao Lv,et al.  A Method for Remotely Sensing Vital Signs of Human Subjects Outdoors , 2015, Sensors.

[19]  J.C. Lin.  Noninvasive microwave measurement of respiration , 1975, Proceedings of the IEEE.

[20]  N. Huang,et al.  The empirical mode decomposition and the Hilbert spectrum for nonlinear and non-stationary time series analysis , 1998, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[21]  Rafael A. Calvo,et al.  Affect Detection: An Interdisciplinary Review of Models, Methods, and Their Applications , 2010, IEEE Transactions on Affective Computing.

[22]  James D. Taylor.  Ultra-wideband Radar Technology , 2000 .

[23]  Tor Sverre Lande,et al.  Thresholded samplers for UWB impulse radar , 2007, 2007 IEEE International Symposium on Circuits and Systems.

[24]  Domenico Zito,et al.  A 90nm CMOS SoC UWB pulse radar for respiratory rate monitoring , 2011, 2011 IEEE International Solid-State Circuits Conference.

[25]  Alessandro Tognetti,et al.  SoC CMOS UWB Pulse Radar Sensor for Contactless Respiratory Rate Monitoring , 2011, IEEE Transactions on Biomedical Circuits and Systems.

[26]  Jean-Pierre Antoine,et al.  Analyzing NMR spectra with the Morlet wavelet , 2008, 2008 16th European Signal Processing Conference.

[27]  Patrick Flandrin,et al.  A complete ensemble empirical mode decomposition with adaptive noise , 2011, 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP).

[28]  Fadel Adib,et al.  Emotion recognition using wireless signals , 2016, MobiCom.

[29]  Changzhan Gu,et al.  From Tumor Targeting to Speech Monitoring , 2014 .

[30]  Md Shariful Islam,et al.  Continuous wavelet transform based analysis of low frequency oscillation in power system , 2015, 2015 International Conference on Advances in Electrical Engineering (ICAEE).

[31]  Ke Wu,et al.  24-GHz Frequency-Modulation Continuous-Wave Radar Front-End System-on-Substrate , 2008, IEEE Transactions on Microwave Theory and Techniques.

[32]  David Girbau,et al.  ANALYSIS OF VITAL SIGNS MONITORING USING AN IR-UWB RADAR , 2010 .

[33]  Jenshan Lin,et al.  0.25 /spl mu/m CMOS and BiCMOS single-chip direct-conversion Doppler radars for remote sensing of vital signs , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[34]  ROBERT WATSON-WATT.  Radar in War and in Peace , 1945, Nature.

[35]  Changzhan Gu,et al.  From Tumor Targeting to Speech Monitoring: Accurate Respiratory Monitoring Using Medical Continuous-Wave Radar Sensors , 2014, IEEE Microwave Magazine.

[36]  Gabriel Rilling,et al.  Empirical mode decomposition as a filter bank , 2004, IEEE Signal Processing Letters.

[37]  M.G.M. Hussain,et al.  Ultra-wideband impulse radar-an overview of the principles , 1998 .

[38]  Antonio Lázaro,et al.  Techniques for Clutter Suppression in the Presence of Body Movements during the Detection of Respiratory Activity through UWB Radars , 2014, Sensors.

[39]  Sung Ho Cho,et al.  Vital sign monitoring of a non-stationary human through IR-UWB radar , 2014, 2014 4th IEEE International Conference on Network Infrastructure and Digital Content.

[40]  G. Charvat,et al.  A Through-Dielectric Radar Imaging System , 2010, IEEE Transactions on Antennas and Propagation.

[41]  Changzhi Li,et al.  Robust Overnight Monitoring of Human Vital Signs by a Non-contact Respiration and Heartbeat Detector , 2006, 2006 International Conference of the IEEE Engineering in Medicine and Biology Society.

[42]  Changzhi Li,et al.  Hybrid FMCW-interferometry radar system in the 5.8 GHz ISM band for indoor precise position and motion detection , 2013, 2013 IEEE MTT-S International Microwave Symposium Digest (MTT).

[43]  I. Erlich,et al.  Wavelet-Based Analysis of Power System Low-Frequency Electromechanical Oscillations , 2011, IEEE Transactions on Power Systems.

[44]  Richard Kronland-Martinet,et al.  Asymptotic wavelet and Gabor analysis: Extraction of instantaneous frequencies , 1992, IEEE Trans. Inf. Theory.

[45]  James Taylor,et al.  The Micropower Impulse Radar , 2000 .

[46]  Xinming Huang,et al.  Real-time non-contact infant respiratory monitoring using UWB radar , 2015, 2015 IEEE 16th International Conference on Communication Technology (ICCT).

[47]  Norden E. Huang,et al.  Ensemble Empirical Mode Decomposition: a Noise-Assisted Data Analysis Method , 2009, Adv. Data Sci. Adapt. Anal..

[48]  Guangyou Fang,et al.  Vital Sign Detection Method Based on Multiple Higher Order Cumulant for Ultrawideband Radar , 2012, IEEE Transactions on Geoscience and Remote Sensing.

[49]  Malek G. M. Hussain.  Impulse Radar - An Overview of the Principles , 1998 .

[50]  A. Stelzer,et al.  Non-invasive respiratory movement detection and monitoring of hidden humans using ultra wideband pulse radar , 2004, 2004 International Workshop on Ultra Wideband Systems Joint with Conference on Ultra Wideband Systems and Technologies. Joint UWBST & IWUWBS 2004 (IEEE Cat. No.04EX812).

[51]  M.R. Mahfouz,et al.  Real-Time Noncoherent UWB Positioning Radar With Millimeter Range Accuracy: Theory and Experiment , 2010, IEEE Transactions on Microwave Theory and Techniques.