Fast Analysis Of Electromagnetic Scattering Properties Of Lossy Dielectric-Metal Structures Based On Eigenmode Method

Repetitive electromagnetic structures have great applications in actual engineering.However,the cost of full-wave simulation calculations for them is too high.Therefore,seeking an accurate and efficient solution method has theoretical and practical importance for guiding the design of repetitive structures.The characteristic modes(CMs)method has received extensive attention in the field of electromagnetics since it was proposed.Since the CMs is only related to the inherent physical properties of the target and has nothing to do with the external excitation,and the modes have natural orthogonality,it is very suitable as the target.The global basis function is used to expand the surface current.Then cut through a few modes to reduce unknown unknowns and improve the calculation efficiency of target electromagnetic problems.This paper mainly studies the analysis of characteristic modes of different repetitive structures.The main work of the paper is summarized as follows:In the first part,considering that the medium part of the medium-metal hybrid repetitive structure is lossy,the extraction method of the characteristic modes of the uniform lossy medium is first studied,and then the characteristic mode extraction of the lossy medium-metal hybrid structure is deduced.Load the characteristic current matrix of the linear element to analyze and find that its characteristic mode will not change with the amplitude of the linear element.The characteristic mode can be multiplexed,which greatly saves the linear element extraction modes with different amplitudes.The application range of the characteristic mode method is wider.The second part considers that in the analysis of the complex repetitive structure of the connection type,in order to ensure the continuity of the current at the cell boundary,a buffer is introduced,which leads to the weakening of the orthogonality between the modes.This paper introduces singular value decomposition to strengthen Orthogonality between modes.When the unit design is more complicated,the dimensionality reduction matrix is inferior.This paper introduces the preconditioning technology,uses the relative distance between the global basis functions to sparse it,and then constructs the preconditioning operator.The construction time and convergence speed of the preconditioning technique are compared and analyzed.Among them,the advantage of approximate sparse inverse preconditioning is outstanding,and the degree of parallelism is high.This paper proposes a parallel approximate sparse inverse preconditioning method for the feature mode method,which has excellent performance in solving electromagnetic scattering problems of complex repetitive structures.Parallel sparse approximate inverse preconditioning Conditional technology makes the characteristic mode method more efficient to analyze the electromagnetic scattering characteristics of complex repetitive structures.