Abstract: The electric field integral equation (EFIE) of the periodical structures is first changed into the matrix equations of frequency derivative and matrix equations of the induced currents using MOM. In the AWE technique, the induced currents of the periodic structures at any frequency within the frequency band can then be obtained from the induced currents of frequency derivative at given frequency via the Pade approximation, then the broadband characteristics of EM induced currents can be fast calculated. It was observed that AWE technique results in more considerable CPU time saving than that uses MOM technique.