Computation of electromagnetic field inside a tissue at mobile communications frequencies

The increasing diffusion of mobile communications is stimulating the study of the interaction mechanisms between electromagnetic (EM) fields and biological systems at radio frequencies. This paper is devoted to the modeling of the interaction between EM fields and a tissue, represented with spherical cells. Different EM approaches have been used to analyze the problem and, in particular, the lumped-element finite-difference time-domain (FDTD) technique has been used to model the cell´s membrane represented with the Hodgkin-Huxley (HH) model, and the Floquet theorem to study a tissue by analyzing only few cells. The EM problem has been solved by using the FDTD technique to be independent from the geometry. Computations have been performed at GSM900 and GSM1800 frequencies overcoming the problem relevant to the computation time by using the quasi-static FDTD technique. The results show the field distribution inside the tissue at GSM frequencies; the effect of the application of the HH model to the membrane is also shown.