Abstract

Detection of the heartbeat rate and/or respiration rate are very important for most radar based applications like lie-detection, life-detection etc. The prediction of signal losses is a fundamental aspect in the design of ultra wide-band radars. The effect of body tissues surrounding the heart is important in the design of a radar system used for heartbeat detection. The broad variety of tissues and their frequency dependent behavior makes accurate attenuation prediction very difficult without the support of an appropriate model. In this paper, two frequency dependent planar electromagnetic models viz. intrinsic impedance model (a classical model) and impedance transformation model, both incorporating dispersive dielectric properties are discussed. Signal attenuations in both models are estimated and compared. This estimation can be helpful in the design of an ultra wideband (UWB) radar system meant for cardio-pulmonary activity related applications.