Calculation of Whole-body Average SARs in Infant Models for Far-Field Exposure over GHz Frequencies

摘要

With much concern about health effects of children for radio-wave exposure, computational studies on whole-body averaged specific absorption rates (WBA-SARs) in anatomically based child models have actively been conducted. For different electromagnetic polarization, we calculated WBA-SARs up to 15 GHz in the Japanese models of 3-year-old child, and 9-month-old and 0-month-old infants with a resolution of 1 mm/0.25 mm. Then, WBA-SARs obtained herein are compared with those estimated from our formula proposed in our previous study. As a result, we found that horizontal exposure polarization provides larger WBA-SARs in infant models than that for the vertical one. The WBA-SARs have rather flat characteristics in the frequency range from 1 GHz to 3 GHz, which become almost constant over 10 GHz. It was also found that the WBA-SARs estimated from the formula are conservative for different exposure polarization. The finding obtained suggests that the reference level at 0.8 GHz in general public exposure is more appropriate levels to limit WBA-SAR for frequencies above a few gigahertzes.