Specific Absorption Rates in the human head due to circular metallic earrings at 1800MHz

This paper investigates Specific Absorption Rates (SAR) in the human head due to circular metallic earrings at 1800MHz. A Finite-Difference Time-Domain (FDTD) code was used to analyse different sizes and positions of circular earrings near a homogenous cubic phantom. Results showed good agreement with measurements using the flat section of the SAM twin phantom with the DASY4 measurement system. The excitation was a half wave dipole. Metallic loops with a circumference of approximately one wavelength and positioned 14mm away from the phantom increased the 10g SAR by 5 times. The FDTD code has also been used to analyse the effect of metallic earrings when ‘pierced’ through the ear of an anatomically realistic digital human head based on the Visible Human Project. The head is not symmetric and both ears were considered to allow comparison between different heads. The shape of the ear and the size of the earring were found to be very significant when earrings were hung from the human ear.