Estimation of Whole-Body Average SARs in Human Models for 0.1-2 GHz Vertically Polarized Far-Field Exposure Using Squares Averaged Over Height of Layer Induced Currents

Abstract

In this study, for the aim of validating whole-body average SARs in human volunteers for 0.1-2 GHz vertically polarized far-field exposure, we calculated with the FDTD method power absorption (product of whole-boy average SAR and weight) and square values averaged over height of layer induced currents in anatomical based human models for Japanese adults and children standing on a ground. As a result, we found that there exist strong correlations between them, and their regression coefficients have over 0.8 coefficient of determination at frequencies from 0.1 to 2 GHz, and are almost kept constant at frequencies from 300 MHz to 600 MHz with over 0.95 coefficient of determination. We also calculated the circumference integral of magnetic near-fields around a human-body model to reveal that the squares of layer induced currents can be estimated from the magnetic near-fields with relative errors of 25% from 300 MHz to 600 MHz and 1.5% at 100 MHz. This finding implies that the whole-body average SAR in a real human for vertically polarized far-field exposure could be estimated from the square values averaged over the height of layer induced currents. Experimental validation of this finding is a future subject.