Large-Area Complex Terrain Radio Wave Propagation Loss Prediction Using Bidirectional Three-Dimensional Parabolic Equations

Based on the parabolic approximation of Helmholtz equation, a three-dimensional (3-D) vector parabolic equation (PE) technique for predicting propagation loss in large region irregular terrain is proposed. The split-step Fourier transform method (SSFT) is used to solve the three-dimensional vector parabolic equation and in order to analysis the backward propagation, a bi-directional parabolic equation model is established. In addition, the absorption boundary conditions and the impedance boundary conditions of the obstacle surface are also studied. Two examples were simulated using the proposed method, one of which is a large-scale real terrain, verifying the accuracy of the method.