Cell addition method for metal strip

There is not an effective method to analyze the electromagnetic scattering of compact periodic metal strip´s structure. In optics, wave follow the principle of Fermat and Snell´s law. In the microwave band, there is scattering of electromagnetic waves propagation. And this metal strip is analyzed in THz. The THz wave has both characteristic of light wave and electromagnetic wave. The cell addition method which has been work-out follows Huygens-Fresnel principle for the compact periodic metal strip. And the real size can be simulated using this method. Finally, the error analysis is shown.