Presentation Information
[B-1A-01]Measurement and Modeling of Rough-Surface Reflection Coefficients at 300 GHz
◎Raichi Sato1, Minseok Kim1 (1. Niigata Univ.)
Keywords:
THz,Rough-surface reflection,Reflection coefficient
In the sub-THz band (100–300 GHz), which is attracting attention for next-generation mobile communication systems, wavelengths are extremely short, on the millimeter order. Consequently, the effects of diffuse scattering caused by the surface roughness and texture of building materials—which were negligible in conventional frequency bands—become highly significant. While specular reflection from smooth surfaces can be calculated using Fresnel reflection coefficients, on rough surfaces such as actual walls, the intensity of the specularly reflected wave is significantly attenuated and fluctuates spatially due to interference and scattering losses caused by microscopic surface irregularities. The effects of rough surface reflection are often modeled by correcting the Fresnel reflection coefficients based on the Kirchhoff approximation. While effective for evaluating average reflection attenuation, this method may not adequately capture the stochastic amplitude fluctuations of specularly reflected waves caused by interference with diffusely scattered waves. Therefore, elucidating fading fluctuation characteristics alongside attenuation characteristics is essential for highly accurate propagation simulations. In this study, we conducted reflection measurements at 300 GHz across 10 levels of surface roughness using sandpapers with controllable roughness.