New formulations of the characteristic basis function method for the analysis of metamaterials

A numerical scheme that combines the Multilevel Fast Multipole Algorithm (MLFMA) and the Characteristics Basis Function Method (CBFM) has been developed for the analysis and design of complex antennas and microwave devices composed by metamaterials and other finite-sized multilayered periodic structures. The main goal is to reduce the computational cost associated to traditional MoM when electrically large structures are analyzed. The method has been tested considering several periodic structures achieving good results.