Specific absorption rate reduction of multi split square ring metamaterial for L- and S-band application

Abstract

In this paper, a framework for investigation on mobile phone and human head interaction are presented for L- and S-band applications. The proposed compact metamaterial design helps to reduce the Specific Absorption Rate (SAR) value that exposed to the human head. A recent achievement in metamaterial field allows this unusual material widely used in mobile phone applications to enhance the accomplishment and consequently received substantial attention among researchers. Hence, a multi-split square ring metamaterial design developed on a 1.6 mm thick dielectric substrate layer known as Epoxy Resin Fiber (FR-4). Electromagnetic properties of the proposed metamaterial structure were calculated through numerical simulation tool using the Finite Integration Technique (FIT) in Computer Simulation Technology Microwave Studio (CST). A few designs were used to conduct parametric studies with altering the substrate material, design structure, array arrangement and phone distance from the human head. 0.3–4 GHz frequency range was utilized in this simulation, where the proposed design established resonance frequencies precisely at 1.81 (L-band) and 3.79 GHz (S-band). The measured results show the resonance frequencies occurred at 1.82 and 3.72 GHz. Therefore, with a little bit discrepancy between the numerical and measurement results, it made the comparison was largely in agreement. The SAR value shows that a reduction by 36.87% and 45.54% at L- and S-band respectively for averaged over 1 g of tissue volume. While for averaged over 10 g of tissue volume, integrated metamaterial design in mobile phone reduced by 35.29% and 48.36% at L- and S-band respectively.