Abstract
This paper proposes a novel low SAR PIFA structure to reduce exposure of the human head to mobile-set antenna radiation. Dual-band PIFA structures operating at 0.9 GHz and 1.8 GHz bands are considered. SAR is decreased by reducing the back-radiation coming from the patch and the ground plane. This SAR reduction is accomplished by inserting a thin metallic layer between the patch and the ground plane to reduce the current flowing in the ground plane. This layer is connected to the ground plane through few posts located at selected optimum positions. Additionally, three vertical sidewalls are used to reduce radiation from the patch to the human head. Results show that the proposed structure can reduce SAR by up to 76%.