Comparisons of Ray-Tracing and Parabolic Equation Methods for the Large-Scale Complex Electromagnetic Environment Simulations

Abstract

It is important for the wireless communication field to conduct research on large-scale complex electromagnetic environment (CEME) simulation. There exist many models for computing CEME simulation, including empirical models, half-empirical or half-deterministic models and deterministic models. Most of these models cannot obtain satisfactory results due to the limitation of the capacity of computers. The ray tracing (RT) and parabolic equation (PE) methods are very suitable for large-scale CEME simulation. Based on the introduction of RT and PE, qualitative comparisons of the two methods are analyzed in view of algorithm theory, the category of the model, solution to the model and the application field, and then four specific indices are focused on to analyze the computational complexity, accuracy, speed and parallelism in details. The numerical experiments are presented by the three-dimensional (3D) RT method employing the software of Wireless InSite (WI) and a quasi-3DPE method using the sliced method. Although both RT and PE methods can achieve high speedup using coarse-grained parallel computing, the experimental results indicate that the PE method can obtain a higher speed than the RT method, and the two methods can acquire an approximate precision. A hybrid procedure using both RT and PE methods can obtain a better result for solving CEME problems.