Study On Higher Order Nystr (?) M Method And Its Fast Algorithm For Metal Time Domain Integral Equations

Computational electromagnetism is an important subject which analyses electromagnetism problems, it plays an important role in various fields. Computational electromagnetism includes a variety of analysis methods, where the frequency-domain and time-domain method are the two main branches of electromagnetism. And the significant difference between the two methods is that the frequency-domain method just solve a frequency point once, but the time-domain method can get the results of different frequencies once solved, thus the time-domain method saves computation time, so one of the advantages of the time-domain integral equation method is to deal with the broadband problem. However, the common time-domain integral equation method use RWG space basis function to be discreted mostly, this Time Domain Surface Integral Equation just can deal with the conformal grid problem, when the model is more non-conformal, the common time domain integral equation method is not applicable, resulting in the time domain integral equation can not be used widely. So a new kind of time domain integral equation method need to be studied.This article combines the higher-order Nystrom method which can deal with non-conformal grid with the time domain surface integral equation method to solve this problem, and applying the modeling rules and point testing rules of higher-order Nystrom method to the time domain integral equation, it makes that when the time domain surface integral equation handles smooth surface target,it uses fewer unknowns on the premise of guarantee accuracy, thereby reducing the memory consumption. This article firstly introduces the basic principles of higher order Nystrom methods and the basic theory of the time domain surface integral equation, then introduces the high-order Nystrom method for solving marching-on-in-order time domain surface integral equation method and the high-order Nystrom method for solving marching-on-in-time time domain surface integral equation method in detail, Finally, against those shortcoming of the time domain surface integral equation which consuming a lot of memory and having a very low efficiency, plan wave time domain is used in the time domain surface integral equation method,and the results is that the memory and time is reduced largely.