Selecting parameters of Type-3 NUFFTs to control accuracy in MoM methods

We discuss how the parameters of 1D Type 3 Non-Uniform Fast Fourier Transform (NUFFT) algorithms based on the Gaussian gridding can be chosen to achieve a prescribed accuracy. Type 3 NUFFT algorithms are of interest in many areas of applied electromagnetics, as for example fast antenna analysis and synthesis and fast calculation of the scattered fields. The approach is related to the one dimensional case and follows the work in A. Dutt and V. Rokhlin, SIAM J. Sci. Comp. 14 (1993). The accuracy of the proposed choice is numerically assessed for an electromagnetic application consisting of the implementation of the aggregation and disaggregation steps in the fast calculation of the scattered field by the Fast Multipole Method.