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The paper deals with the determination of the absorbed power density (Sab) in a planar multilayer model of a tissue exposed to the radiation of a dipole antenna, based on the analytical/numerical approach. A derivation of Sab from the differential form of Poynting theorem is presented. The two-layer and three-layer tissue models are used. Illustrative analytical/numerical results for electric and magnetic fields and Sab induced at the tissue surface for various antenna lengths, operating frequencies and antenna-interface distances are presented in the paper. Exposure scenarios of interest pertain to frequencies above 6GHz pertaining to 5G mobile systems.

The paper presents results for the induced field and the absorbed power density (Sab) at the surface of the planar multilayer model of the human tissue due to radiation of dipole antenna obtained by means of analytical/numerical approach. The influence of multi-layered domain is taken into account via the Fresnel plane wave reflection/transmission approximation. Numerical procedures pertain to Galerkin-Bubnov Indirect Boundary Element Method (GB-IBEM). Some illustrative examples for various frequencies, dipole lengths and distances of dipole from the interface are given.

International audience; Currently, most state-of-the-art research in computational dosimetry utilizes flat-surface tissue models to simplify the problem geometry and thus mitigate computational complexity. However, depending on the ratio of the penetration depth and the curvature radius, this may lead to a non-correct estimation of the power absorbed by the tissues due to constructive/destructive interference. In this study, we propose an accurate evaluation of the area-average absorbed power density in curved tissueequivalent models by computing the surface integral of the normal component of the absorbed power density vector field. The numerical analysis is performed for plane wave exposure of an ear model at 60 GHz. We also investigate the effect of the averaging area shape on the absorbed power density by considering 1 cm(2) square- and disk-shaped averaging surfaces. Results show a substantial relative difference of 14 % in the areaaveraged absorbed power density over a disk-shaped averaging surface between transverse electric and magnetic polarization, with the reference being the value of the area-averaged absorbed power density for a planar homogeneous model and normal incidence. By using the same reference value, negligible differences of 1.81 % and 0.92 % for transverse electric and magnetic polarization, respectively, are present when the averaging area shape changes. According to the studied exposure scenarios, the area-averaged absorbed power density variations as a function of the averaging surface geometry are less significant than those related to the polarization of the incident field.