Rician Fading Models for Rough Surface Reflection at 300 GHz

Compared to existing frequency bands, terahertz (THz) waves are more susceptible to diffuse scattering due to surface roughness, and this effect must be considered when predicting propagation paths using deterministic methods like ray tracing. In this study, an experimental investigation of the reflection characteristics of plasterboard-a common indoor wall material-at 300 G Hz is conducted. First, this paper proposes a rough surface reflection model, incorporating both specular and diffuse components, which result in small-scale fading through interference. Rician fading models for plasterboard reflection at 300 GHz are then presented, based on extensive measurements under four different conditions: bare plasterboard, paper-covered plasterboard, painted plasterboard, and painted plasterboard wall. The results reveal that the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$K$</tex> -factor ranges from 11.06 to 26.32 dB, with the specular component being more prominent in the TE mode than in the TM mode.