THz Time-Domain Spectroscopy of Human Skin Tissue for In-Body Nanonetworks

This paper presents experimental study of real human skin material parameter extraction based on terahertz (THz) time-domain spectroscopy in the band 0.1-2.5 THz. Results in this paper show that electromagnetic properties of the human skin distinctively affect the path loss and noise temperature parameters of the communication link, which are vital for channel modeling of in-body nanonetworks. Refractive index and absorption coefficient values are evaluated for dermis layer of the human skin. Repeatability and consistency of the data are accounted for in the experimental investigation and the morphology of the skin tissue is verified using a standard optical microscope. Finally, the results of this paper are compared with the available work in the literature, which shows the effects of dehydration on the path loss and noise temperature. The measured parameters, i.e., the refractive index and absorption coefficient are 2.1 and 18.45 cm^-1, respectively, at 1 THz for a real human skin, which are vital for developing and optimizing future in-body nanonetworks.