Abstract: The method of moments (MOM) in conjunction with the asymptotic waveform evaluation (AWE) technique is applied to calculate the electromagnetic scattering directional characteristics of one-dimensional frequency selective surfaces (FSS). The electric field integral equation (EFIE) of FSS irradiated by the electromagnetic (EM) wave is firstly changed into the matrix equations of the induced currents using MOM, and the matrix equations of an angular derivative (MEAD) can be then obtained from the matrix equations. In the AWE technique, the induced currents of angular derivative at a given angle within an angular are first obtained to find MEAD. The induced currents at any angle within the angle can be then obtained from the induced currents of an angular derivative at given angle via the Pade approximation. According to the induced currents and the Floquet harmonic of the spectral domain, the EM scattering directional characteristics can be calculated. It was observed that the results of AWE can exactly approximate those of MOM that sweeps frequency at a certain interval, and AWE technique can result in considerable CPU time saving.

Key words: AWE technique, FSS, MOM, fast algorithm, EM scattering