The radiation absorption distribution of electromagnetic energy into the breast phantom is of fundamental
importance in understanding its therapeutic capability emitted by the microstrip applicator for noninvasive
hyperthermia procedure. In this paper simple microstrip applicator with rectangular shape is
presented. Different operating frequency were investigated to observe radiation absorption distribution,
which is measured through specific absorption rate (SAR) parameter. The operational frequency was
915MHz and 2450MHz, the industry, scientific and medical (ISM) frequency range. As simulated by
using the finite difference time-domain (FDTD) computational simulation which is known as SEMCAD
X solver, the results shed an interesting observation on the SAR when frequency varies, which is shown
by the transformation onto the penetration depth and focusing capability onto the breast area to be treated.