Effective Resistance of Grounded Humans for Whole-body Averaged Sar Estimation at Resonance Frequencies

Whole-body averaged specific absorption rate (WBASAR) is used as a metric for human protection from whole-body exposures. The frequency at which the WBA-SAR becomes maximal is called “resonance frequency”. The present study proposes a scheme to estimate WBA-SAR at the resonance frequency based on an analogy between a human and a quarter-wavelength monopole antenna. Specifically, WBA-SAR can be estimated with the human body resistance once ankle current was obtained. Thus, it is essential to investigate the effective resistance for anatomically-based human models. Then, the effective resistances for different humans grounded on the perfect conductor are calculated to clarify the variability. The main factors for the variability were attributed to the body shape and model anatomy. In particular, WBA-SARs in human models grounded are found to be estimated from their BMI and respective measured ankle current in realistic environment, including a scenario of multiple wave exposure.