Em Energy Absorption in the Human Body Tissues Due to Uwb Antennas

This paper presents electromagnetic energy absorption in the homogeneous and layered human body models due to body-worn UWB antennas, at frequencies of 3, 6 and 8 GHz. Typical small planar UWB antennas are used in this study: printed UWB disc monopole and UWB slot antenna. Distances of 2, 5 and 10 mm (reactive near-field region) between antennas and human body were chosen, approximating realistic scenarios of operation in Wireless Body Area Networks. To approximate different parts of the human body, or body variations among different users, we compare results obtained for the planar homogeneous (muscle) model with those for three-layer body models (skin, fat and muscle), with different thicknesses of the skin (0.5– 2 mm) and fat (1–9 mm) tissue. For these body models we investigate the electromagnetic energy absorption mechanism by examining the peak 1-g SAR and peak SAR (without mass averaging). Based on our results we present and discuss new finding concerning the general electromagnetic energy absorption mechanism in human tissues under reactive near-fields exposure conditions.