Abstract
The implicitly restarted generalized minimum residual method (IRGMRES) combined with the fast Fourier transform (FFT) technique is developed for solving three-dimensional (3-D) weak-form volume electric field integral equation of electromagnetic scattering problems. On several electromagnetic scattering problems, the resulted IRGMRES-FFT method converges two-three times faster than the conventional biconjugate gradient (BCG)-FFT method. Comparison with other Krylov-subspace iterative fast Fourier transforms methods also demonstrates the efficiency of the IRGMRES-FFT method.