Improvement on the convergence of modified discrete convolution method for scattering from a finite periodic structure

A modified discrete convolution method (MDCM) is presented. It is based on formulating the conventional discrete convolution method (DCM) and zeroing the Frobenius norm of the iterative matrix. The storage space and the multiplicative operations of MDCM are almost the same as that of DCM, but the former is convergent more stably than the latter. This modified method is suitable to the electromagnetic scattering or radiation problems with electrically large geometry, especially to the problem with a finite periodic structure