Investigation of Water Vapor Absorption in the THz Spectral Region for Future Wireless Communications

With the sixth generation (6G) of wireless communications aiming to move towards the terahertz (THz) region of the electromagnetic spectrum (0.1 - 3 THz), there is an inherent need to study the effect of atmospheric gases, primarily water vapor, on the transmission of THz radiation. In this work, we implement a sensitive THz spectroscopy system with a variable path length to characterize the propagation distance of THz radiation under humid conditions. We show spectral windows with negligible absorption of THz radiation and have grouped them into three channel categories for: short-, mid- and long-range communication based on the maximum THz propagation distance reached at 35% relative humidity.