| There are two methods according to equation form in electromagnetic scattering numerical analysis:one is integral equation method, the other is differential equation method.Compared to the differential equation method, the integral equation method has two advantanges:Firstly, the discretization area is just on the surface or in the volume of scatterer. Secondly, without absorbing boundary conditions, radiation conditions are satisfied automatically in the integral equation by the Green's function.This thesis is based on the frequency-domain integral equation and the electromagnetic scattering characteristic of conductor objects is investigated.Above all, the fundamental theory of method of moments (MOM) is introduced,as well as the process of electromagnetic problems analyzed by the MOM, then, the frequency-domain integral equations for analyzing scatter characteristics of perfect conductor objects are described.Then put forward an improved method.After gainning the induced current computed by the electric field integral equation,the current is used to calculate scattering magnetic field,then adding the incidence magnetic field in order to get the total magnetic field. so, the high precision induced current can be computed.The precision is higher than the traditional method of moments about a order of magnitude, and can eliminate the interior resonance effectively. When the object is discretized roughly, high precision still can be obtained. Numerical results show that this method can improves the efficiency and precision, especially for electrically large objects.In solving electric field integral equations, fast multipole is used to make the computing efficiency greatly improved. And compare the results of two-dimensional perfect conduct using fast multipole with the results solved by traditional method of moments, fast multipole has a clear advantage in computation time and memory. It has a more evident efficiency in solving electrically large objects.
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