A novel implementation of truncation number for improving accuracy of MLFMA

For multilevel fast multipole algorithm (MLFMA), we develop a novel method that adopted different precision control in different levels for truncation number calculation and investigate the effect on calculation precision caused by nodes number in detail used in the two-dimensional Lagrange interpolation, we improve the interpolation method which chose different nodes number in different levels. The improvement could enhance the precision and efficiency of calculation notably concluded from the numerical results. It could meet the algorithm requirement of electromagnetic scattering for complex three-dimensional targets.