Dosimetry and Temperature Evaluation of TEM Chamber for Cell Exposure at 1800 MHz

Abstract

Using the finite-difference time-domain (FDTD) method, we make a dosimetry study on the specific absorption rate (SAR) in cells exposed to 1800 MHz standing waves produced by the transverse electromagnetic (TEM) chamber. Two types of cultured cells are used, namely, the cell layer and the cell suspension. Based on the calculated SAR distribution, the exposure is characterized by the SAR intensity and homogeneity. We consider different exposure arrangements as the combination of the maximum fields of the standing wave and the polarizations of the Petri dish. The maximum E field and maximum H field are used in turn in the exposure volume, where the Petri dish is polarized in the E, H, k and k directions, respectively. The best exposure arrangements are determined by measuring the intensity and homogeneity of the SAR distribution in cells. For a tight control of the thermal environment, the temperature rise in the cell culture induced by the exposure is calculated by using the finite-difference formulation of the bio-heat conduction equation. The linear relation between the maximum temperature rise and the absorbed power is determined to quantify the exposure power for the temperature control.