Interpolation scheme for efficient computation of the reaction terms in the Characteristic Basis Functions Method (CBFM)

In this paper we present a technique to accelerate the evaluation of the mutual coupling between blocks when using the Characteristic Basis Functions Method (CBFM) to compute the electromagnetic scattering by PEC structures. The scatterer is modelled by NURBS surfaces. A Lagrange interpolation method is used together with a sampling scheme which takes into account the relative distance between the blocks. Numerical results show a good accuracy in the computation of the electric field on the test surface, also in the case of adjoining blocks.