Numerical Diffraction of Array-Guided Surface Waves on Finite Frequency Selective Surfaces

In this paper, an adaptation of Hurst´s method to take into account the presence of array guided surface waves in the calculation of the scattered field of finite frequency selective surfaces in free space is presented. Numerical approaches to determine the guided wave´s wavenumber needed in this calculation, namely Prony´s method and the discrete Fourier transform (DFT), are examined and compared. The results show that the scattered fields obtained with the proposed method, which is based on numerically extracted diffraction coefficients, are in very good agreement with those obtained with the method of moments.