Analysis of Heuristic Uniform Theory of Diffraction Coefficients for Electromagnetic Scattering Prediction

Abstract

We discuss three sets of heuristic coefficients used in uniform theory of diffraction (UTD) to characterize the electromagnetic scattering in realistic urban scenarios and canonical examples of diffraction by lossy conducting wedges using the three sets of heuristic coefficients and the Malyuzhinets solution as reference model. We compare not only the results of the canonical models but also their implementation in real outdoor scenarios. To predict the coverage of mobile networks, we used propagation models for outdoor environments by using a 3D ray-tracing model based on a brute-force algorithm for ray launching and a propagation model based on image theory. To evaluate each set of coefficients, we analyzed the mean and standard deviation of the absolute error between estimates and measured data in Ottawa, Canada; Valencia, Spain; and Cali, Colombia. Finally, we discuss the path loss prediction for each set of heuristic UTD coefficients in outdoor environment, as well as the comparison with the canonical results.

A Modified Radiopropagation Multipath Model for Constant Refractivity Gradient Profiles

“…( 16), it is possible to obtain a fourth degree equation: where the coefficients are defined in terms of δ and the variables exhibited in Fig. 3, as shown from expression (18) to ( 22) [17]:…”

“…The UTD formulation considers the 2-D problem of diffraction by a semi-infinite wedge with straight edges. The geometry and wedge diffraction variables involved in the formulation can be seen in [18]. The distances between the source and the wedge, and between the wedge and the observation point, are calculated with the optical length equation [11].…”

A Critical Review on Channel Modeling: Implementations, Challenges and Applications

“…For shorter tunnels, the most crucial point is either the radiations from the free space of mobile station are falling within the tunnel vicinity or, contrariwise, the diffusion of external waves exist within the tunnel. The coupling between outside and inside is handled through a uniform theory of diffraction [44].…”

Heuristic UTD Solution for Antennas Near a Complex Platform

“…The heuristic works in [13,14] based on [8] can deal with the non-PEC structure with corners. Recently, the heuristic UTD solution is used for outdoor environment in [15]. The preliminary results of UTD solution for corner and slope diffraction were presented in [16].…”