An application-independent multilevel fast multipole code for the analysis of curvilinear surfaces with wire attachment

The multilevel fast multipole algorithm (MLFMA) has been shown to provide substantial improvement over traditional method of moments (MOM) in the analysis of interconnections of linear surfaces and wires. In order to reduce the number of unknowns involved in modeling surface and wire structures with a high degree of curvature, the curvilinear RWG basis and the curvilinear wire basis are applied to expand the current distribution on curved surfaces and wires. The techniques for singularity extraction proposed by Champagne, Williams and Wilton (1992) are extended for the curvilinear RWG basis. In the present work, the original MLFMA code is modified to be an application-independent library similar to ScaleME. The aim is to hide the details of MLFMA implementation and let users exploit the power of MLFMA through a simple interface. For users who have a general MOM code with arbitrary basis functions, they only have to write support functions for computing the impedance matrix elements and radiation and receiving patterns of each basis function. Then, they can call the functions in the MLFMA library to setup MLFMA-related parameters and to accelerate the matrix-vector multiplication with the freedom of using any iterative matrix solver.