ELECTROMAGNETICS, cilt.29, sa.4, ss.303-320, 2009 (SCI-Expanded)
This article presents a review of diffraction algorithms based on the uniform theory of diffraction for multiple building transition zone diffractions and proposes an improved uniform theory of diffraction model for fast and more accurate field prediction for multiple diffractions. The proposed method is based on the improved version of the slope uniform theory of diffraction and Fresnel zone concept, called the slope uniform theory of diffraction with convex hull. This article also provides a comparison for uniform theory of diffraction based algorithms and discusses the results for computation time and accuracy. Furthermore, the slope uniform theory of diffraction and the slope uniform theory of diffraction with convex hull methods are compared with a physical optics solution based on numerical computation of the Kirchhoff-Huygens integrals. Results of extensive simulations are presented and discussed for the development of fast and accurate radio network planning tools.