Compressive Sensing For Solution Of Electromagnetic Scattering Over Wide Angle

Following the development of modern electromagnetic(EM) engineering, the problem of EM scattering have become an important research areas in computational electromagnetic(CEM), In particular, fast and efficient analysis of EM scattering characters of electrically large object over a wide angle has theoretical and practical significances.The method of moments (MOM), as one of the main numerical methods to solve electromagnetic scattering problems, has been widely used to solve a variety of problems in CEM. The basic idea of MOM is to reduce a functional equation to a matrix equation by expending a functional equation into an unknown function and being tested by the weight function. Considering the radiation boundary conditions satisfied automatically, without analytical solution, the calculation results of MOM with higher accuracy is often used as a reference solution for other methods. However, to solve electromagnetic scattering problems of wide-angle by MOM, in addition to a small number of interpolation and approximation, there is no effective technology, and ones has to repeat calculation at each angle, for large object, which consumes a huge amount of computer resources.To overcome the problems mentioned above, the dissertation systematically discusses the subject of ""application of compressive sensing(CS) to solution of electromagnetic scattering problems over wide angle". The CS technique is introduced in conjugation with MOM, which committed to the fast and efficient analysis of wide-angle electromagnetic scattering problems of the two-dimensional objects of different shapes and materials.Specific studies include:(1) The MOM, which is used to complete the scattering analysis of two-dimensional conducting and the dielectric object, is systematically studied, and compressive sensing is also considered. Furthermore,basis MOM computation codes for solution of2-D scattering problems and compressive sensing codes are developed, which lays a good foundation for the forthcoming work.(2) Considering the impedance matrix in MOM is independent from the incident angle, we introduce the CS technique to construct a new incident source, in which much information about incident angle is included, so a new technique is introduced to solution of electromagnetic scattering problems over wide angle.(3) According to the nature of the excitation current, several sparse basis matrix, which representation of the excitation current more sparse, are structured, thereby reducing the number of observations of the compression current. The numerical results show:the computation time reduce greatly based on the good reconstruction accuracy.(4) Based on the spare banded matrix and spare rank matrix, a new spare measurement matrix was structured. We compared random and the new spare measurement matrix, experimental result showed that the later was better. Key words:method of moments, compressive sensing, sparse basis matrix, electromagnetic scattering problems over wide angle.