MoM And The Application Of MoM In Analyzing Scattering And Radiation Characteristics Of Arbitrary Conductors

Method of Moment (MoM) is a method which can discretize continuity equation into algebraic equations, and it is one of the most popular methods in analyzing the electromagnetic radiation and scattering problems. This dissertation focuses on the use of MoM based on Electric Field Integral Equation (EFIE) to study the traits of radiation and scattering of various kinds of arbitrary shape PEC targets. The main research of this paper is to study the arbitrary shape wire antennas'direction characteristics and impedance characteristics.First of all , this paper uses pulse expansion and the RWG current basis function based on the triangular surface. When triangular bin is used, firstly, simulates geometric figure on the surface of object; then builds EFIE; at last, the EFIE is transformed to Matrix Equation using the Galerkin method (RWG vector base functions are basis function and test function). When obtain the electric current, it is easy to get some other parameter such as input impedance and direction characteristics. Because RWG is lower-order basis function and using more unknown element, the paper tries to use fewer unknown elements and more accurate high-order RWG vector basis function for analysis.Secondly, the calculating of electromagnetic problem using MoM is mainly reflected in filling impedance matrix and solving linear equations. It is inevitable to emergence singularity points when solves the impedance matrix. This paper mainly focuses on calculation of the impedance matrix and treating of the singular points. Gauss integration and nine-point integration are used to calculate impedance matrix, and the potential integration method and singular value transfer method are used to solve the integral singularity problem.Finally, according to examples, application of MoM based on EFIE solves, the scattering and radiation problems of arbitrary shape PEC targets, particularly, the direction of the characteristics and impedance characteristics (including the symmetric half-wave dipole antenna, Yagi antenna, helical antenna, etc.). We get all the data and results through the program implementation, which provide a theoretical basis for carrying out antenna in project.