The Study Of The Time-domain Integral Equation Method Based On Equivalence Principle Algorithm

Along with the development of electronic technology, how to stablely, accurately and fastlyanalyze the transient electromagnetic response of objects are becoming more and more important.But most of the research is concentrated in the frequency domain algorithm, so the time domainmethod has been more and more important in analyzing the transient electromagnetic scatteringproblems.Until now, marching-on-in-time method (MOT) is still the most commonly used methodin solving the time domain integral equation (TDIE). But there exists a fatal demerit in MOTmethod, which is the problem of late time unstability that limits its application.Marching-on-in-order method uses the weighted laguerre polynomials as its temporal basisfunctions, which can get unconditional stability solution.Equivalence principle algorithm (EPA) is a domain decomposition scheme based on theequivalence theorem. EPA shows its advantages especially in solving the multi-object or repeatedobjects scattering problems. Equivalence surface (ES) is introduced to enclose subscatterer. It isseen that the unknowns on the scatterer are transferred to the unknowns on its ES with theinformation of the scatterer meanwhile. So the intercoupling effect between region and region aretransferred to calculate the interaction of its surrounding equivalent surface. As the choosing ESsare often in regular patterns, so the subdivision size can be larger and the unknowns on equivalentsurface will be smaller than the subscatterer. Then the iterative steps will be significantly reducedand accordingly the cycle times are massively saved as the needed impedance matrix is of goodcondition.In this thesis, the EPA combined with TDIE is introduced to analyze transient electromagneticscattering problems for repeated metal objects. Some numerical results are given to present theefficiency of the proposed method.