A numerical approach to electromagnetic dosimetry for the human body

The quantitative evaluation of the human hazard due to exposure to nonionizing radiation requires the estimation of the em. absorption by the various tissues of the human body. In this paper, a numerical method is proposed, which can be used to predict the distribution of electromagnetic absorption inside the human body (simulated by a 3D block model consisting of variable-sized cells). Electromagnetic scattering is studied, taking into account the mutual coupling between the source (i.e., an antenna) and the body. A moment-method formulation is adopted to reduce to matrix form the well-known integro-differential equation of direct electromagnetic scattering and the equations of the boundary conditions of the electromagnetic source. A domain decomposition is performed that allows one to use limited computational resources and to perform an off-line evaluation of the invariant model portions. Simulations results are reported, concerning the block model of a standard man (175 cm tall) made up of 450 cells and exposed to the aperture antenna. The abdominal region is considered in more detail. Such results are compared with those obtained under plane-wave exposure of a two-dimensional cylindrical model.

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