Numerical Evaluation of SAR for Compliance Testing of Personal Wireless Devices

This paper presents the numerical evaluation of the specific absorption rate (SAR) calculated with the finite integration technique (FIT) using a glass spherical head model and a λ/2 cylindrical dipole antenna. The model is filled with appropriate frequency-specific fluids with electrical properties that are close to the average brain tissue at the center frequencies 0.835 and 1.9 GHz. The dependence of the peak SAR on the distance between the head and the antenna is evaluated. It is shown that the peak SAR decreases as the distance between the head and the dipole antenna increases. The calculated peak average SAR in the head is compared with SAR limits in the safety standards for compliance testing of wireless devices. The calculated results of SAR variations in the head model and their dependence on the distance between the head and the dipole antenna are also compared with the measured results from literature. All numerical simulations are performed using the CST Microwave Studio software. Simulation results are in good agreement with published measurement results and are within ±13% for spherical head model.