Augmented MLFMM for solving the electromagnetic scattering problems with fine structures

Efficient Computation of Wideband RCS Using Singular Value Decomposition Enhanced Improved Ultrawideband Characteristic Basis Function Method

“…where Z represents the impedance matrix between and blocks. Typically, the dimensions of the reduced matrix Z R are smaller than that generated via the conventional MoM, and can be obtained by directly solving (4). In this way, the surface current at any frequency point can be obtained.…”

“…The method of moments (MoM) [1] is one of the most popular numerical methods used for radar cross section (RCS) prediction, but it places a heavy burden on memory and solving time while dealing with electrically large problems. A number of different fast solution methods have been proposed to circumvent this problem such as the fast multipole method (FMM) [2], the multilevel fast multipole method (MLFMM) [3,4], the adaptive integration method (AIM) [5], the adaptive cross approximation (ACA) algorithm [6], and the characteristic basis function method (CBFM) [7,8]. Many electromagnetic applications require the solution of the radiation from an antenna or the scattering problem over a wide frequency band rather than at a single frequency point.…”

Analysis of Wide Band Scattering From Objects Using the Adaptive Improved Ultra-Wide Band Characteristic Basis Functions

“…Moreover, in order to obtain the RCS over a wide frequency band using MoM, the calculation at each frequency point has to be repeated over the band of interest which increases computational time. A number of efficient methods, such as the fast multipole method (FMM) [2], multilevel fast multipole method (MLFMM) [3,4], adaptive integration method (AIM) [5], adaptive cross approximation (ACA) algorithm [6], and characteristic basis function method (CBFM) [7,8], have been proposed to improve the calculation efficiency at single frequency point. However, if the RCS is highly frequency dependent, then the calculations are required to be performed at finer increment of frequency to obtain an accurate representation of the frequency response which is computationally intensive.…”