The CGM and the FDTD for SAR studies

In the study of electromagnetic radiation effects over dielectric bodies, effective numerical methods are needed. At present, there is a lack of tools for measuring these effects and due to the huge growth of microwave devices, like cellular radio telephones working close to the human body, it is necessary to develop accurate numerical methods for evaluating those effects. Two of the most efficient and extensively used methods are the FFT-CGM (fast Fourier transform-conjugate gradient method) and the FDTD (finite difference time domain method). Since both methods use a rectangular grid, it is interesting to compare the two solutions in order to validate the results. Algorithms for solving the two-dimensional scattering of transversal magnetic (TM) polarized waves by a lossy dielectric objects are presented. At the same time, the SAR (specific absorption rate) of tissues is obtained from the diffracted fields.