Stable Solution Of The Exact Time Domain Integral Equation Analysis Of The Broadband Antenna

With the development of research in electromagnetic pluse and ultra-wide band communication, the analysis of arbitrary electromagnetic radiation and scattering by time domain method attracts more and more attention. The time domain integral equation (TDIE), which has both the advantage of integral equation method and time domain method, should be widely applicated. However, some problems such as instable and inaccurate exist in the marching-on-time (MOT) method for solving time domain integral equation, and limit the application of time domain integral equation. The studies of this thesis are mainly concentrated on accurate computation of impedance matrix elements to get accurate and the stable solution of the time domain integral equation, and its application in antenna radiation with modeling the coaxial feed line by magnetic frill source. The thesis is composed of the following three parts.1. The research background of solving electromagnetic problems by time domain integral equation is reviewed. First, the style of time domain integral equation for perfect electronic conducter and the basic idea of marching-on-time method for solving time domain integral equation are given. Next, the space basic function and time basic function which are widely applicated or chosen by the thesis are introduced. At last, the description of numerical algorithms to solving the matrix equation and physical concept in electromagnetic radiation and scattering are maken.2. An accurate and stable marching-on-time method using spline temporal basis functions. First, the scalar potential function, the vector potential function and the curl of the vector potential function should be transformed to accurate style as the arc length function in space and convolution in time. Then the analytical expression of convolution of potential function and temporal basis function in style of polynomial is shown to get the accurate impedance matrix elements of time domain integral equation. At last, numerical results demonstrate the stability and accuracy of the proposed method.3. An accurate and stable marching-on-time method using spline temporal basis functions is combined with modeling the coaxial feed line by magnetic frill source, to analyze the radiation of wire antenna on perfect electronic conductor object. First, the basis theory of magnetic frill source model and the style of its in TDIE are introduced. Next, the numerical results and its discussion are given, and the accuracy of the proposed method apllicated in radiation of wire antenna on perfect electronic conductor object is demonstrated.