Complex permittivity of human skin in vivo in the frequency band 26.5-60 GHz

With the increasing use of millimeter-wave radiation in communications and radar, it is necessary to know the dielectric properties of various tissues for the evaluation of potential hazards to humans. At millimeter-wave frequencies, the absorption of electromagnetic radiation is mostly restricted to the skin because of the submillimeter depths of penetration. So, knowledge of the dielectric properties of human skin in vivo is of prime importance for quantifying the hazardous effects of millimeter-wave radiation. In the past, the dielectric properties of excised human skin tissue have been measured below 30 GHz. Also, the dielectric properties of human skin in vivo have been reported in the 100 MHz-2 GHz frequency range by many researchers. Hay-Shipton et al. (1982) have reported complex permittivities of human skin (palm) in vivo in the 8-18 GHz range. In this paper, we report the complex permittivity data for human skin (palm) in vivo in the frequency range 28-57 GHz.