Incident Power Densities on Temporal Head Surfaces Over the Standard and Anatomical Models: A Computational Study from 20 to 70 GHz
Kensuke Sasaki, Tomoaki Nagaoka, Teruo Onishi · 2023
With the expansion of the use of technologies, such as 5G systems, using quasi-millimeter and millimeter waves in the general environment, the public concern regarding human exposure to electromagnetic fields (EMFs) has been increasing. Therefore, conformity to the exposure limits of human exposure to EMFs should be assessed appropriately prior to the launch of new wireless technologies in public and working environments. In recent years, IEC/TC106 and IEEE/ICES/TC34 published IEC/IEEE standards of conformity assessment procedures by measurement [1] and computational [2] approaches. In these standards, the procedures to assess the peak spatial average (e.g., 1cm 2 or 4 cm 2 ) of incident power density, which is the metric of reference levels for local exposure to EMFs above 6 GHz to 300 GHz in the exposure guidelines [3] and standard [4] of non-ionized radiation protection, were provided. We have been focusing on the applicability of a virtual phantom, which is referred to as "the held-at-ear evaluation surface" in the IEC/IEEE standards [1][2], and we have reported the exposure levels on the virtual phantom derived by computational simulation with those on the temporal head models for an adult human assuming the condition where the device is held near the ear at 28 GHz In this study, we extend our previous work conducted at several frequencies from 20 to 70 GHz, which covers frequencies of 5G systems (which also includes potential frequency). In addition, the exposure levels were assessed using not only the surface head model for adult and the head model specified in the international standards [1][2] but also the surface head model for child As a result, we found that the head model of the international standard statistically simulates the exposure level of the human models in the considered exposure scenarios as well as our prior work at 28 GHz.