Averaging Area for Transmitted Power Density Correlated to Temperature Elevation on Human Skin Surface due to RF Exposure at 60 GHz

This study investigated the averaging area of the power density inside the human body due to RF exposure from the antennas operated at 60 GHz. We conducted a computation evaluation of the transmitted power density and the local temperature elevation on the surface of a glycerine phantom with a dielectric property close to a human skin tissue. The measured near-field distributions of several typical antennas were used in the FDTD simulation. The analytical results indicate that the transmitted power density averaged over an area smaller than 4 cm2 is needed to correlate with the local peak temperature elevation at 60 GHz. This finding is valuable for discussing how to use the transmitted power density as metric to evaluate the beam exposure at millimeter wave frequencies.