Time-lapse imaging of human heartbeats using UWB radar

Abstract

Radar systems for detection of human heartbeats have mostly been single-channel systems with limited spatial resolution. In this paper, a radar for ultra-wideband (UWB) imaging of dynamic reflectors inside the human body is presented. To make the radar waves penetrate the human tissue a body-contact antenna is used. The antenna is an array with eight elements, and an antenna switch system connects the radar to the individual elements in sequence to form an image. Successive images are used to build up a time-lapse movie of the beating heart with a frame rate of 25 Hz. Measurements on a human test subject are presented and heartbeat waveforms are extracted at specific locations inside the body. The experiments indicate sufficient resolution for observation of different moving parts of the heart and may provide basis for live diagnosis.