Research On The Method Of Three-dimensional Parabolic Equation Based On Alternating Direction Decompositio

With the rapid development of the times,people’s requirements for communication quality are becoming more and more strict.Accurate prediction of radio wave propagation characteristics in complex environments has become a premise and guarantee for improving the quality of communication.The parabolic equation(PE)method has been widely used in predicting the propagation of radio waves in the ground and sea environment because of its efficiency and stability.The three-dimensional parabolic equation(3DPE)method is the most commonly used when simulating the propagation of radio waves in the real environment.The3 DPE method can not only predict the radio wave propagation characteristics in space more accurately,but also save a lot of computing resources compared to the ray tracing and wave-guide mode theory.In order to achieve rapid prediction of the radio wave propagation characteristics in large areas,it is also necessary to optimize and innovate the 3DPE method to reduce the amount of calculation and shorten the calculation time.This thesis has done the following work based on the analysis of the propagation characteristics of radio waves in large-area scenes based on the 3DPE method:First of all,the two-dimensional and three-dimensional scalar-parabolic equation models are deduced,and the step-by-step Fourier solution method,initial field and boundary conditions of the corresponding equation models are described.And then,the process of the vector parabola equation based on the potential function is deduced.The vector parabola equation takes into account the polarization effect of the electromagnetic field and can more accurately obtain the distribution of the space field.Then,for the propagation problem in a large area above the surface,the alternate direction decomposition split-step Fourier algorithm optimization algorithm is proposed.This algorithm can greatly reduce the calculation time when calculating the wave propagation loss characteristics in the large area environment.On this basis,the Open MP parallel strategy is added,and the calculation time is further shortened,which makes the parabolic equation have application value in predicting the problem of radio wave propagation in a large areas.Afterwards,based on the above parabolic equation models,the problem of radio wave propagation in the marine environment is analyzed.The influences,which are caused by marine atmospheric ducts,rough seas,island topography on the propagation of radio waves are also considered.Then,combined with the three-dimensional bidirectional parabolic equation method,the efficient simulation of radio wave propagation in the marine environment is realized,and the method is compared and verified with the method in the reference.Finally,the Digital Elevation Model(DEM)is used to analyze the propagation of radio waves in the real geographical environment.By importing physical data information,a real geographic structure is constructed.A parabolic equation method based on the partition principle is proposed to calculate the transmission field inside the model,which reflects the propagation characteristics of radio waves more realistically.