Reduction of Electromagnetic Absorption in the Human Head for Portable Telephones by a Ferrite Sheet Attachment

Abstract

From the standpoint of reducing the electromagnetic (EM) absorption in the human head for portable telephones, a ferrite sheet is proposed to use as a protection attachment between the antenna and the head. By using an anatomically based head model and a realistic portable telephone model, the effects of the ferrite sheet on both the reduction of EM absorption and antenna radiation pattern are numerically analyzed by the finite-difference time-domain (FDTD) method. The results show that a ferrite sheet can result in a reduction over 13% for the spatial peak SAR averaged over one gram of tissue relative to a degradation below 0.6 dB for the antenna radiation pattern.