Research on Fast Algorithm of Radio Wave Propagation in Low-Lossy Obstacles Environment

Abstract

To predict the propagation of radio waves in the environment of dielectric ground and dielectric obstacles, a new two-way parabolic equation (2W-PE) method based on the domain decomposition principle and surface impedance boundary conditions (SIBC) is proposed. First, we decompose the obstacle area into different subdomains and derive the SIBC in each subdomain in detail; then, the discrete hybrid Fourier transform (DMFT) in the upper subdomain and finite difference (FD) algorithm in the lower subdomain is used to solve 2W-PE combined with SIBC, respectively. After that, we explain the algorithm steps in the process of calculating the total field, compared with the traditional 2W-PE, and then finally introduce the method of moments (MoM) combined with the enhanced discrete complex image (E-DCIM) method for accuracy verification of the new 2W-PE algorithm. The simulation results show that no matter how the obstacle medium parameters change, the results of 2W-PE method proposed in this paper and MoM are always in good agreement, which proves the accuracy of 2W-PE and its superiority in speed. Therefore, this paper provides a reliable and efficient method for solving the problem of radio wave propagation in the presence of obstacles, especially in the case of low-lossy obstacles.

Predicting Spatial Field Values Under Undulating Terrain With 2W-PE Based on Machine Learning

“…9. Compared with the results of the traditional 2W-PE from [7], the new 2W-PE is more accurate in the entire space, which is the result of considering the internal propagation and choosing appropriate BCs. The calculation mesh of MoM is finer, so its accuracy display has a higher resolution.…”

“…For the case of rectangular flat-topped obstacles, we introduced the 2W-PE algorithm based on the DD method [7] to calculate the spatial field strength inside and outside the obstacle. As shown in Fig.…”

“…The corresponding refraction angles are, respectively, θ p2 and θ q2 . Thus, IBCs obtained by downward waves, respectively, in Ω 1 and Ω 2 are expressed as [7]…”

“…Digital Object Identifier 10.1109/LAWP.2021.3123836 field value to diverge. In [7], we introduced the surface IBC into 2W-PE for the first time to achieve calculation stability, but its applicable situation is too simple.…”

An Efficient and Accurate 2W-PE Method for Solving Spatial Field Strength Based on CVNN and PINN

“…Since then, the traditional 2W-PE [10,11] and its solution method [12][13][14] have been continuously developed, but traditional 2W-PE ignores the calculation of the spatial feld inside the obstacle, which will cause a large error in the case of a low-lossy obstacle. In response to the abovementioned problems, in our previous research [15][16][17], we proposed a 2W-PE that considers multiple refections inside the obstacle based on the principle of domain decomposition. Ten, we used the split-step Fourier transform (SSFT) and FD methods to solve the 2W-PE with boundary conditions to determine the feld values of the areas above and inside the obstacle, respectively.…”