Effects of frequency, permittivity, and voxel size on predicted specific absorption rate values in biological tissue during electromagnetic-field exposure

Current electromagnetic-held (EMF) exposure limits have been based, in part , on the amount of energy absorbed by the whole body, However, it is known that energy is absorbed nonuniformly during EMF exposure, The development a nd widespread use of sophisticated three-dimensional anatomical models to c alculate specific-absorption-rate (SAR) values in biological material has r esulted in the need to understand how model parameters affect predicted SAR values. This paper demonstrate the effects of manipulating frequency, perm ittivity values, and voxel size on SAR values calculated by a finite-differ ence time-domain program in digital homogenous sphere models and heterogene ous models of rat and man. The predicted SAR values are compared to empiric al data from infrared thermography and implanted temperature probes.