Frequency Domain Analysis Of Electromagnetic Scattering From Nonuniform Medium Based On Rotational Symmetry

In the field of Computational Electromagnetics, the Method of Moment is a kind of efficient method to analyze the scattering properties of targets. With the development of Moment methods, analyzing electrically large medium targets has become a trend. To achieve this goal, two main schemes will be introduced here. One is for the targets which have the rotationally symmetrical structure. It can be transformed the three dimension targets into two dimension to improve the computation efficiency. The other is the domain decomposition method (DDM), which can be decomposed an electrically large target into some small targets.The first method is based on the idea of body of revolution (BoR) to calculate the inhomogeneous dielectric. Fourier series can be used to transfer the problem of three dimension to a two dimensional problem for the rotational symmetric structure. And then a transverse plane of the body is needed to select to discretize its two dimensional grid. Because of the orthogonality between the various modes of Fourier series, the equivalent current of each mode is independent of each other. Finally, the equivalent current can be added which is calculated separately in each mode. This can greatly reduce the number of unknowns and thus improve the computational efficiency. Furthermore, the paper also analyzes the body which is the mixed structure of metal and medium. This thesis verifies the correctness by comparison with FEKO or Mie series, and verifies the efficiency by comparison with the program of volume integral equation (VIE) and volume-surface integral equation (VSIE).The second method is the thought of DDM, which decomposes the inhomogeneous dielectric body to several small areas. This method is based on the idea of equivalence principle algorithm (EPA). It can speed up the convergence speed and reduce the memory cost. The method can calculate any objects which is different from the first method. In addition, multilevel fast multipole method (MLFMM) is used here to improve the computational efficiency. This thesis verifies the correctness by comparison with FEKO or Mie series, and verifies the efficiency by comparison with the program of volume integral equation (VIE).