| The calculation of electromagnetic scattering problems has been widely used in all walks of life these days,ranging from the science and engineering of national defense to personal mobile phones and computers.It involves a wide range of fields.How to quickly solve electromagnetic scattering problems has always been a very popular scientific research topic.In recent years,methods based on computational electromagnetics have received sufficient attention in the field of electromagnetic scattering.Among them,the method of moments(Method of Moments,MoM)has been widely used in various fields as a method of integral equations.Compared with the same types of methods in computational electromagnetics,the method of moments has the highest accuracy in the solution process,but as the size of the calculation target becomes larger,the calculation efficiency of the method of moments will drop sharply,first in the calculation time Above,because the traditional method of moments needs to calculate the double integral,the complexity of direct and indirect solutions are respectively and,followed by the memory problem of the storage matrix.The storage complexity of the method of moments algorithm is that the calculation time and storage memory problems are both As the dimension of the matrix increases exponentially,at the same time,how to extend the method of moments to a wider range of scenarios has always been a difficult point to solve the problem of electrically large conductors.Therefore,the academic community is concerned about how to reduce the calculation of the method of moments.Research on complexity,time complexity and how to solve the problem of electrically large conductors has been ongoing.The main work of this article has carried out related research around the above-mentioned problems of the method of moments,and the main contents are as follows:1.Starting from the electromagnetic scattering model,the relevant formulas of the method of moments are derived in detail,and the RWG(Rao-Wilton-Glisson)basis function is used for related programming and calculation,and the centroid split method is used to solve the problem of the Ingreen function.There is a singularity problem caused.When the distance between the field point and the source point is greater than 0.15 wavelengths,the EDM(Equivalent dipole moment)equivalent dipole moment model is used to accelerate the filling of the matrix equation,which greatly reduces the impedance matrix.Filling time.2.Use ACA(Adaptive cross approximation algorithm)to compress the impedance matrix.At the same time,in order to remove the redundant blocks of the matrix formed in the ACA algorithm,the algorithm is further improved,using RACA(Recompression adaptive cross approximation algorithm).The recompression adaptive cross-approximation algorithm further optimizes the algorithm.3.In the solution of the electrical problem,this paper proposes to use a related hybrid algorithm—Method of Moments-Physical Optics·(Method of Moments-Physical Optics,MoM-PO)to solve it,systematically introduces and derives the method of physical optics The related formulas and the two types of physical optics methods are finally integrated in an iterative manner,and the related fast algorithms of the method of moments and the iterative physical optics method are jointly applied to related electrical problems.4.In view of the actual scene,the rough surface is introduced,especially the electromagnetic scattering problem of the sea surface,and the common sea spectrum is introduced and modeled.Finally,the relevant calculation examples verify that the algorithm in this paper is effective in solving the electromagnetic scattering problem of objects on the sea surface.High efficiency and reliability,which shows that the research content of this article has certain validity for solving the actual situation. |
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