Surface electric field distributions of lightweight phantom composed of wave absorber for simplified SAR measurement

In recent years, the use of wireless communication devices that are used in close proximity to the human body has been increasing, and there has been growing concern about the effects of human exposure to electromagnetic waves radiated close to the human body. For this reason, a simplified method for measuring the specific absorption rate is required. In this paper, a flat-plane lightweight phantom comprising a radio wave absorber is considered as an alternative to a liquid phantom. The electrical parameters of the lightweight phantom are determined to be such that the amplitude of its surface impedance is identical to that of the surface impedance of the liquid phantom; the parameters are determined by using transmission-line theory. When a finite-difference time-domain (FDTD) method is used to determine the distributions of the electric field, the surface distributions of the electric field on the flat-plane lightweight phantom are found to be identical to those using a liquid phantom. Finally, surface distributions of the electric field using the lightweight phantom are determined from measurements and compared with those obtained using the FDTD method.