The averaging procedure of the electrical properties at the interface of dissimilar tissues in the human head using the FDTD method at 1800 MHz

The FDTD method builds a problem space out of finite sized Yee cells. The interfaces between heterogeneous materials can be treated in different ways. This paper investigates different techniques for calculating the effective permittivity and conductivity at dissimilar tissue interfaces. An anatomically realistic head is considered and effects are found to be significant with anatomically realistic heads. The effects are particularly apparent if internal structures in the head are near resonance. The paper shows that the choi ce of averaging technique is important and choice referred to wherever such results are presented.