SAR and Temperature Increase in Human Bodies Due to On-Body Communications

• Main Authors: Heng-Ming Li, 李恆銘
• Other Authors: Hsing-YiChen
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/55262309825514423730

碩士 === 元智大學 === 通訊工程學系 === 100 === The research work focuses on electromagnetic energy absorption and temperature increase in a human model due to on-body communication systems. The specific absorption rates (SAR) and temperature increase in an inhomogeneous human model with ten types of tissues were studied by using the finite-difference time-domain (FDTD) method under the irradiation of a patch antenna located at different locations on the human body surface at 900 and 2450 MHz. From simulations results, it is found that the maximum local SAR occurs in the skin and decreases sharply as the distance increases from the skin. Maximum local SARs of 0.03 and 0.9 W/kg are obtained in the skin at 900 and 2450 MHz, respectively. It is also obtained that the highest layer-averaged SARs are in the order of 10-4~10-3 and 10-3~10-2W/kg for the patch antenna located on different locations on the human body surface at 900 and 2450 MHz, respectively, that are far below the ANSI/IEEE safety guideline of 1.6 W/kg for 1 g of tissue or 2 W/kg for 10 g of tissue in uncontrolled environments. It is also found that the maximum temperature increases of 1.2????-3 oC and 6.3???-4 oC occur in the left chest for 1 g of tissue and 10 g of tissue at 900 MHz, respectively. The maximum temperature increases of 2.5????-2 oC and 5.0???-3C occur in the heart for 1 g of tissue and 10 g of tissue at 2450 MHz, respectively. The maximum temperature increase of 2.5????-2 oC is far below the threshold temperature increase of 4.5 oC for neuron damage for more than 30 minutes and the temperature increase of 10 oC for thermal damage in the skin.