Moment Method & Lts New Development

Some analysis is done by the use of Moment Method on the study of the near field and the surface field scattered by the metal plane body. And Asymptotic Waveform Evaluation is introduced to some problems to improve the Moment Method. Lastly the problem that singular integral exists in the use of Moment Method is investigated in this paper. Some work are done as follows: 1 The scattering problem of plate induced by plane waves is studied in this paper. The current density of plate by the scattering is computed by moment method. Some preparations are done for the count of surfaces field and near field. A new approach is brought forward for the singular integral problem during the computation process. 2 AWE is used in reference to fast evaluate the radar cross section in wide-angle band with MM to save time. However, Considering the fact that the impedance matrix is independent of the incidence angle, the author uses the inversed impedance matrix multiplied by the excitation matrix of different angles to avoid the waste of time by repeatedly solving the matrix. The conclusion is drawn. For the scatter of small size and the case that the curve of RCS is smooth with the incidence angle, AWE is less efficient than the matrix inversion. 3 AWE if analyzed for the fast computation of RCS with frequency. Some problems that might appear are discussed in detail. For the first time, AWE is used in a new field: antenna optimization design. When the antenna is sensitive to the frequency, to widen the working band, different frequencies are selected to repeatedly analyze the same process. AWE is introduced into this problem, to fast get the antenna character in all the frequency band and save a lot of time in optimization process. 4 For the problem that singular integral exists in the numerical computation of electromagnetic problems with MM, for the first time, an expression is put up of conductor surface current and charge distribution with the skin effect considered, to avoid the singular problem. Examples are given to verify the result.