THz-FDS Characterization of Building Materials and Extension of the ITU-R P.2040 Model for Sub-THz Frequencies

Thanks to large available bandwidths and unique propagation characteristics, terahertz (THz) communication systems offer the potential for high-throughput, low-latency communications, while also enabling precise sensing capabilities. The accurate modeling of THz channels in indoor environments - such as offices, meeting rooms, hallways, and living rooms - requires precise knowledge of the dielectric properties of common building materials. In this paper, we present the characterization of the most common building materials between 100 and 400 GHz, including window glass, ceiling board, floorboard, wood, plywood, plasterboard, brick, marble, concrete, and chipboard samples. Our measurements have been carried out using a custom setup based on a state-of-the-art frequency-domain spectroscopy system. To ensure an accurate material characterization, we developed a custom beam-guide fixture and an ad hoc signal processing pipeline. Using our measurements, we extend the ITU-R P.2040 model by deriving custom parameters to describe the dielectric properties of these materials. The results of this study contribute to the improved modeling of wireless channels at sub-THz frequencies.