Walls effect over the specific absorbtion rate in the human head due to mobile phone exposure

The purpose of this paper is to determine the specific absorption rate (SAR) in the human head in 10 g of mass tissues due to mobile phone exposure with walls nearby. The mobile phone was modeled as a λ/4 monopole antenna placed at a distance of 1 mm from the human head and the SAR values were determined using CST software for two GSM frequencies, 900 and 1800 MHz taking into consideration different placements of the walls in the head vicinity and antenna positions too. As a particular application SAR was determined when the human head is situated inside a metallic cage whose dimensions are comparable with an elevator cabin.