A new UTD-based model for multiple diffractions by buildings

In this paper, the most rigorous UTD (uniform theory of diffraction)-based expressions for multiple diffractions by buildings and excess path losses in urban cellular mobile environments are derived and analyzed. For this purpose, buildings are supposed to have rectangular shapes with the same heights and spacings. Also in this analysis, actual electrical properties of buildings are used. Previous studies have been concentrated on the simplified models that buildings were approximated as absorbing half-screens or perfect conducting half-screens (knife-edges) or 90 degree wedges. In this work, buildings are assumed to be flat-roofed parallel rows of dielectric blocks, and their actual dielectric constant and conductivity are applied.