ACCURACY OF BIO-ELECTROMAGNETIC CHARACTERISATION AND COMPUTATION
Keywords:Bio-electromagnetics, characterisation, induced field computing, Finite Element Method
Evaluation of the induced effects of electromagnetic fields in the human body requires firstly good knowledge of the electrical properties of tissues and secondly efficient computing tools. Firstly, the accuracy of a usual characterisation method is studied using a 3D Finite Element model coupled to electrical circuit equations. It is shown that the relative errors on the measured conductivity and permittivity are respectively 2% and 15% on the 10Hz-10MHz frequency range. Then, the accuracy of the numerical computing of induced fields is studied using various Finite Element formulations applied to a 2D canonical problem. It is shown that a high frequency formulation together with efficient boundary conditions gives the best results on the whole 10Hz-10GHz frequency range.
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