Efficient interpolation scheme for multilevel fast multipole algorithm

An efficient interpolation scheme which is bilinear interpolation for multilevel fast multipole algorithm (MLFMA) is presented. Bilinear interpolation is simple, easy to implement and has quadratic interpolation behavior. Numerical results show that bilinear interpolation achieves good performance even in complex model when compared to bicubic and Lagrange interpolation which is commonly used in MLFMA implementations.