Research And Application Of Electromagnetic Modeling Method For Micro/Rough Structure Of Electrically Large Platform

With the frequency of electromagnetic wave becoming higher and higher and the wave length becoming more and more short, the traditional smooth surface, in fact, will become micro-rough surface. The micro-roughness can not be ignored and the surface should be treated by rough surface. The traditional method to deal with the rough surface is Monte Carlo Simulation, but it is very time-consuming. So in this paper we study the Stochastic Integral Equation Method(SIEM), an efficient method which can be used to compute the electromagnetic characteristics of random rough surface. Based on the SIEM, this paper makes a systematic study and research work.Firstly we describe the research background and the Significance in the introductory part and introduce the development history and the domestic and foreign research trends of the SIEM. Then the contribution and innovation of this paper are given, and the overall structure of this paper is described.Because of the base of the SIEM is traditional integral equation method, so next we study the Method of Moment(Mo M) and the Electric Field Integral Equation(EFIE),which is the traditional method to solve the electromagnetic problem. We study and research the key points and difficult points of the Mo M and EFIE, such as the selection of basis functions, the solution of impedance matrix, the treatment of singularity and the different iterative methods for solving matrix.In the third chapter, we study the SIEM for the electrostatic problem and the basic theory is derived and elaborated. Then taking the two dimensional infinite conductor as an example, we calculate the surface charge distribution and the capacitance of unit length.In the fourth chapter, after the correctness of this theory is verified by theoretical numerical results, extension of this method is carried out to solve the electromagnetic scattering problem,which includes the 2D and the 3D problem. Compared with the Monte Carlo method, the SIEM is feasible and more efficient.Then we study a fast algorithm for the Electromagnetic problem of random rough surface. The fast algorithm is based on the Multilevel fast multipole algorithm and the Characteristics of Gauss random rough surface. In the near group, we use Statistical calculation to get the impedance matrix elements, but in the far group, we use theapproximate calculation to calculate the elements. The result is in good agreement with the SIEM.