Evaluation of SAR and Temperature Elevation Using Japanese Anatomical Human Models for Body-Worn Devices

This paper investigates the relationship between averaged SAR (Specific Absorption Rate) over 10g mass and temperature elevation in Japanese numerical anatomical models when devices are mounted on the body. Simplifying the radiation source as a half-wavelength dipole, the generated electrical field and SAR are calculated using the FDTD (Finite-Difference Time-Domain) method. Then the bio-heat equation is solved to obtain the temperature elevation due to the SAR derived using the FDTD method as heat source. Frequencies used in the study are 900MHz and 1950 MHz, which are used for mobile phones. In addition, 3500MHz is considered because this frequency is reserved for IMT-Advanced (International Mobile Telecommunication-Advanced System). Computational results obtained herein show that the 10g-average SAR and the temperature elevation are not proportional to frequency. In addition, it is clear that those at 3500MHz are lower than that at 1950MHz even though the frequency is higher. It is the point to be stressed here is that good correlation between the 10 g-average SAR and the temperature elevation is observed even for the body-worn device.

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