Time-Frequency Analysis of Terahertz Radar Signals for Rapid Heart and Breath Rate Detection

Abstract : We develop new time-frequency analytic techniques which facilitate the detection of a person's heart and breath rates from the Doppler shift the movement of their body induces in a terahertz radar signal. One straightforward means of doing such an analysis is the following: take the spectrogram of the ridgeline of the spectrogram of the radar signal. Instead of following this approach exactly, we consider an alternate method in which the ridgeline of the radar signal's spectrogram is replaced with a signal computed from spectral centroids. By using spectral centroids, rather than the ridgeline, we produce a smooth signal that avoids traditional problems with ridgelines, such as jump discontinuities and overquantization. This new method for time-frequency analysis uses a Toeplitz matrix-based algorithm that has a fast Fourier transform-based implementation, and permits centroids of the vertical strips of the spectrogram of the radar signal to be computed without ever having to explicitly compute the spectrogram itself.

[1]  J. Wiltse.  History of Millimeter and Submillimeter Waves , 1984 .

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

[3]  Vesa T. Peltonen,et al.  Computational auditory scene recognition , 2002, 2002 IEEE International Conference on Acoustics, Speech, and Signal Processing.

[4]  Ronen Marmorstein.  7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER , 2006 .

[5]  C. H. Durney,et al.  An Investigation of the Use of Microwave Radiation for Pulmonary Diagnostics , 1976, IEEE Transactions on Biomedical Engineering.

[6]  Jenshan Lin,et al.  A microwave radio for Doppler radar sensing of vital signs , 2001, 2001 IEEE MTT-S International Microwave Sympsoium Digest (Cat. No.01CH37157).

[7]  Boualem Boashash,et al.  Time-Frequency Signal Analysis and Processing , 2002 .

[8]  P. Siegel.  Terahertz Technology , 2001 .

[9]  Nancy Argüelles,et al.  Author ' s , 2008 .

[10]  M. Grigioni,et al.  Optical Vibrocardiography: A Novel Tool for the Optical Monitoring of Cardiac Activity , 2006, Annals of Biomedical Engineering.

[11]  Eugene F. Greneker.  Radar sensing of heartbeat and respiration at a distance with security applications , 1997, Defense, Security, and Sensing.

[12]  Stephen McAdams,et al.  Instrument Sound Description in the Context of MPEG-7 , 2000, ICMC.

[13]  P. Siegel.  Terahertz technology in biology and medicine , 2004, 2004 IEEE MTT-S International Microwave Symposium Digest (IEEE Cat. No.04CH37535).

[14]  Florian Michahelles,et al.  Less contact: heart-rate detection without even touching the user , 2004, Eighth International Symposium on Wearable Computers.

[15]  Kun-mu Chen,et al.  An X-Band Microwave Life-Detection System , 1986, IEEE Transactions on Biomedical Engineering.

[16]  P. Coleman,et al.  Present State of the Millimeter Wave Generation and Technique Art--1958 , 1959 .

[17]  A. Karimi,et al.  Master‟s thesis , 2011 .

[18]  Joerg F. Hipp,et al.  Time-Frequency Analysis , 2014, Encyclopedia of Computational Neuroscience.

[19]  Yong Huang,et al.  Microwave life-detection systems for searching human subjects under earthquake rubble or behind barrier , 2000, IEEE Transactions on Biomedical Engineering.

[20]  Huey-Ru Chuang,et al.  Automatic clutter-canceler for microwave life-detection systems , 1991 .

[21]  Anssi Klapuri,et al.  Musical instrument recognition using cepstral coefficients and temporal features , 2000, 2000 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.00CH37100).

[22]  James C. Lin,et al.  Microwave Apexcardiography , 1979 .

[23]  Thomas P. Flanders,et al.  Performing Organization Name(s) and Address(es) , 2001 .

[24]  Albrecht Schmidt,et al.  Applying wearable sensors to avalanche rescue , 2003, Comput. Graph..