A Domain Decomposition Algorithm For Time - Frequency Integral Equations Based On Rotational Symmetric Equivalent Source

In the field of computational electromagnetics, in order to analyze the complex separated targets more efficiently, domain decomposition method (DDM) has been developed. To analyze the scattering problem of repeated objects, a new technique based on the equivalence principle algorithm (EPA) was proposed in the thesis. It was also combined with the DDM and the method of moments for the body of revolution (BoR-MoM).In frequency domain, multiple coated targets were divided into several subdomains and each region was surrounded by the imaginary equivalent surface. To exploit the BoR-MoM algorithm, the equivalent surface can be made to be spherical surface. In the calculation of interaction between the corresponding equivalent surfaces, BoR basic function was used to discrete equivalent surface. With the proposed method, unknowns can be decreased and the calculation efficiency was also improved. Because of the spherical equivalent surface, the two equivalent surfaces were coaxial, thus scattering matrix with orthogonal mode was obtained and the purpose of reduction in the dimension was realized. Meanwhile, the adaptive cross approximation algorithm (ACA) was exploited to speed up the interaction among equivalence surfaces. In the part of self-interaction, the multilevel fast multipole method (MLFMM) was used to accelerate the computations and decrease the memory requirements.In order to study electromagnetic scattering characteristics of separating metal targets in a wide-band, the time domain integral method based on Marching-on-in-Degree (MOD) was used to solve this problem. Similar as the above DDM method for coated targets, BoR-MoM was introduced to the method based on MOD, significant memory and computing time reduction can be obtained.