Study On The Hybrid Algorithm For Electromagnetic Scattering Of The Object

In this thesis, the hybrid algorithm for electromagnetic (EM) scattering of the object is studied, which improved the calculated efficiency of the electric large target. The main work and results are as follows:1. The basic method of calculating electromagnetic scattering is discussed. The method of moment (MoM), physical optics method (PO) and iterative physical optics method (IPO) are highlighted. The numerical examples of each method are given.2. The way to calculate the EM scattering of one dimensional rough surface by MoM is discussed. The two-dimensional hybrid current-based method is presented in detail, and the formulation of this hybrid algorithm is derived. Then the bistatic scattering of an object located on one dimensional rough surface is computed by this hybrid algorithm. The major influencing factors of this hybrid method are discussed in detail by the numerical results.3. The formulation of PO based on triangular facets is derived, and the object is subdivided into MoM region and PO region further. The hybrid expressions for the EM scattering from the arbitrary shape three-dimensional target are obtained by using the combination of PO and MoM. For the purpose of the continuity of currents, the MoM is selected the RWG basis function. At last, the radar cross section (RCS) of the composite target is computed by the proposed hybrid method. Numerical results are compared with the MoM results and shows that the proposed scheme is more efficient.