Development of an efficient rigorous technique based on the combination of CBFM and MLFMA to solve very large electromagnetic problems

A numerically efficient approach for the rigorous computation of scattering and radiation problems is presented. This technique is based on the combination of the Characteristic Basis Function Method (CBFM) and the Multilevel Fast Multipole Algorithm (MLFMA), and it is intended to deal with very large cases where an iterative solution process cannot be avoided, even considering the matrix size reduction reached by the CBFM. The combination of these techniques avoids the need of computing and storing the terms in the reduced coupling matrix that are not in or close to the diagonal, optimizing the CPU-time and the memory storage requirements.