Pulse pressure monitoring through non-contact cardiac motion detection using 2.45 GHz microwave Doppler radar

The use of a Continuous Wave (CW) quadrature Doppler radar is proposed here for continuous non-invasive Pulse Pressure monitoring. A correspondence between the variation in systemic pulse and variation in the displacement of the chest due to heart is demonstrated, establishing feasibility for the approach. Arctangent demodulation technique was used to process baseband data from radar measurements on two test subjects, in order to determine the absolute cardiac motion. An Omron digital Blood pressure cuff was used to measure the systolic and diastolic blood pressures from which the pulse pressure was calculated. Correlation between pulse pressure and cardiac motion was observed through changes induced due to different postures of the body.