Radiation performance and Specific Absorption Rate (SAR) analysis of a compact dual band balanced antenna

Abstract

This paper presents a compact dual-band dipole antenna with meander line radiating elements. The proposed antenna has a balanced structure with dimensions of 35×6×1.52 mm3, and mounted on a 36.2 × 100 mm2 floating ground plane. The balanced operation of the design is validated by incorporating a differential feed in the software simulation and a 180 ° hybrid junction is used for measurement with the network analyzer to verify the balanced concept of the prototype. Simulated and measured results of the S-parameters along with the de-tuning of the antenna in the presence of the human body shows good agreement. Moreover the proposed design is used as an exposure source to the simulated human head model. The human head is modeled as six layers in the Electromagnetic (EM) software HFSS to study the interaction between the proposed balanced antenna and the human head model. The Electric field (E-field) distribution in the six layers of the human head model is shown to estimate the penetration of the field when the antenna is placed at a distance of 7 mm from the proposed design. Also Local Specific Absorption Rates (SARs) and average SARs simulation results at 3.78 GHz and 4.29 GHz are shown. The SARs analysis showed that in all the six layers of the human head model, local SAR values are greater in fat and Cerebrospinal fluid (CSF) for both the frequencies while the average SAR values are not very high.