Remote cardiac monitoring using radar

Abstract

Recording a patient's vital signs without physical contact is a challenging research problem with applications in medicine, search and rescue, and security. In order to study this problem, an ultra wide band (UWB) pulse radar and a fixed-frequency amplitude based radar were constructed and evaluated. The UWB radar was not reliable and did not produce repeatable results, but the fixed-frequency radar successfully recorded heartbeat signatures from twelve human subjects at a distance of 0.5 - 3 meters. The effects of several variables on the results were analyzed. Two experiments conducted to determine the physiological source of the radar amplitude modulations suggest that the modulation is from chest movement, not electrically induced impedance changes.