Research And Application Of Model Order Reduction In Electromagnetic Scattering

With the development of science and technology and the increase of demand,electromagnetics is facing more and more challenging tasks.The limitations of traditional eletromagnetic methods,such as MoM,FEM,FDTD,have emerged.The study is based on this backdrop.The subject of this paper is Model Order Reduction fast technique and the paper is focus on several sub-methods in Moder Order Reduction like Asymptotic Waveform Estimation(AWE),Chebyshev Estimation and Well-conditioned Asymptotic Waveform Estimation(WCAWE)based on MoM and FE/BI.The study consists of four parts.1.First,MoM and FE/BI are introduced.The principles of them,the formations of the discrete matrices and solution,the elaboration of some details like how to choose basis function and test function,how to deal with singularity of the equations,the introduction of some preconditioners and the analysis of matrices condition.Also,some examples are given to verify the effectiveness and accuracy of them.2.Non-overlapping domain decomposition method(DDM)applying to FE/BI.Mainly described the principles of DDM and to accelerate the convergence of FE/BI through alter transmission condition from the first order Robbin TC to the second order TC.3.Second,AWE,Chebyshev Estimation based on MoM are studied.Mainly explained the principles of these two methods and given four examples as well as the strength and shortness of each method and the range of their application.4.Third,AWE,Chebyshev Estimation and WCAWE based on FE/BI are studied.Mainly explained the principle of AWE and given two examples as well as the strength and shortness of each method and the range of their application.5.In the process of studying MORe technique,some conclusions emerged.For AWE,it has unstable figures and poor ability to fit wide frequency bandwidth because of its lack of orthogonalization for every vector quantity and the intrinsic limitation of Taylor series and Pade Approximation.And it need several frequency points to fit a wide band.For Chebyshev Estimation,although it has no advantage in near-field calculation for its expand order number and time consuming in very high,it has slightly advantage in far-field calculation.For WCAWE,compared with MoM,AWE,it has very excellent superiority in broadband matching and the value is stable for its every new vector is orthogonal to every vectors produced before.