Temperature elevation in Japanese head models for local SAR with different averaging Mass

The present study investigates the relationship between the mass-averaged specific absorption rate (SAR) and temperature elevation in anatomically based Japanese head models due to the dipole antenna. The frequency region considered is from 1 to 6 GHz. Our attention is focused on the averaging mass of SAR, which maximizes the correlation with local temperature elevation. An averaged SAR over 10 g was found to reasonably correlate with local temperature elevation even for frequencies from 3 to 6 GHz, although the correlation became relatively worse as compared with lower frequencies. The dominant factor influencing the correlation is suggested to be the thermal diffusion length and the penetration depth of electromagnetic waves. The correlation of local temperature elevation to mass-averaged SAR is was influenced by 10% or less due to the pinna, model heterogeneity and the antenna position relative to the head model.