Simulating specular reflections for point cloud geometrical database of the environment

Laser scanning of physical environments allows us to construct their accurate structural database. This database is called a point cloud. Radio channel prediction employing the point cloud is a promising new method for millimeter-wave (mm-wave) frequencies. Reported works that predict the radio channel based on the point cloud utilizes a diffuse scattering model with reasonable accuracy if the environment under consideration is small and diffuse dominant. Specular reflections are also crucial propagation phenomena at mm-wave frequencies. However, a mathematical formulation to predict specular reflections is still lacking. This paper presents the formulation for simulating specular reflections based on a point cloud geometrical description of an environment. It evaluates the total specular reflected field as a coherent sum of the individual field contributions originating from the elementary surfaces over an area approximately equal to the first Fresnel reflection zone. The numerical and experimental results demonstrate the accuracy of the proposed formulation.