A versatile microwave plethysmograph for the monitoring of physiological parameters

IEEE Transactions on Biomedical Engineering - Tập 49 Số 10 - Trang 1204-1210 - 2002
G.B. Gentili1, V. Tesi1, M. Linari1, M. Marsili2
1Department of Electronics and Telecommunications, University of Florence, Florence, USA
2Department of Clinical Physiopathology, University of Florence, Florence, USA

Tóm tắt

A simple microwave technique for in vivo monitoring of human pulmonary and cardiac activity is here presented. The technique is based on detecting the changes in the modulation envelope of amplitude modulated waves passing through the human body. A simplified human chest model was developed, proving an unambiguous correlation between heart blood filling and microwave transmission through the chest. A prototype system for transmittance measurement was realized at the 868.5-MHz operating frequency, demonstrating the feasibility of a small, low cost microwave plethysmograph. In vivo measurements showed a good agreement with numerical simulations.

Từ khóa

#Condition monitoring #Biomedical monitoring #Humans #In vivo #Amplitude modulation #Microwave theory and techniques #Envelope detectors #Biological system modeling #Heart #Blood

Tài liệu tham khảo

10.1109/10.464380 10.1109/8.650074 10.1109/74.180638 0, FEKO v3 1 2 10.1088/0031-9155/41/11/003 10.1023/A:1026511515005 10.1109/TBME.1978.326376 10.1109/NTCMWS.1995.522889 ray, 1988, <emph>in vitro</emph> impedance of biological tissues in the frequency range 0.1 to 1.3 ghz, J Electromagnetic Waves & Applications, 2, 429, 10.1163/156939388X00099 penaz, 1973, photoelectric measurement of blood pressure, volume and flow in the finger, Dig 10th Int Conf Medicine and Biological Engineering, 104 10.1109/IEMBS.1988.94456 10.1109/CIC.1988.72587 lin, 1986, microwave propagation in biological dielectric with application to cardiopulmonary interrogation, Medical Applications of Microwave Imaging barbini, 1980, prospects for the application of microwaves in diagnosis and monitoring of pulmonary diseases, Alta Frequenza, xlix, 68 10.1109/IEMBS.1992.592784 10.1109/PROC.1982.12341 10.1109/TBME.1985.325454 li, 1979, microwave apexcardiography, IEEE Trans Microwave Theory and Techniques, mtt 27, 618 hayes, 1998, quantitative investigation of artefact in photo-plethysmography and pulse-oximetry for respiratory exercise testing, Proc CNVD 97 VDI Frontiers in Computer-Aided Visualization of Vascular Functions, 117 0, CST Microwave Studio v 3 10.1006/jcph.1994.1159