UWB pulse propagation in human tissue: Comparison between Gaussian and square waves shape

The detection and the viewing by the radar waves in the opaque medium are going to establish in the coming years a strategic stake in the area of biomedical application. This work studies the performance of Ultra-Wide Band (UWB) signals. These signals have to be sent towards the human body to detect the heart beatings. In previous works, the estimation of UWB pulse attenuation in the human tissue was made by FDTD method or the Friis formula. This paper presents a comparison study between two waves shape; the first one is a Gaussian pulse wave and the second one is a square. These signals have the same central frequency. The comparison of performance of signal is done at the antenna level and the propagation medium. An impedance of 50 Ω characterizes the transmitter antenna. The propagation medium is modeled by four superimposing layers characterized by semi-infinite thickness, dielectric constant and conductivity. ULB wave propagation in such a medium is modeled by the “Finites Differences Time Domain method (FDTD)”. This method is a discretization in time and space of Maxwell's equations in order to find a space-time evolution of the electromagnetic field.