A UTD Solution for Multiple Rounded Surfaces

Abstract

This paper describes the diffraction mechanism when a ray optical field is obstructed by a cascade of smooth convex obstructions. A new formulation of the uniform theory of diffraction (UTD) is presented that incorporates the slope diffraction term. The solution follows a generic approach that can be applied to arbitrary placed convex structures. It will be shown that the slope diffraction term provides the required accuracy in radio propagation predictions when more than one obstruction exists in the propagation path. The proposed solution is then compared with measurements and other analytical models with excellent agreement. It is also found that the presented slope-UTD solution seems to be superior in terms of computation time and complexity, while achieving very accurate results. In addition, when the radius of the cylinder tends to be very small, the solution approaches the UTD solution for multiple knife-edge predictions.