Electromagnetic Scattering by a Perfectly Conducting Patch Array on a Dielectric Slab

The scattering characterization of an infinite and truncated periodic array of perfectly conducting patches on a dielectric slab is discussed. In particular, an approximate solution is presented for the truncated array scattering based on the exact solution for the corresponding infinite array. The last is obtained numerically by solving for the patch currents via a conjugate gradient-fast Fourier transform (FFT) technique, eliminating a need to generate and store the usual square impedance matrix. The scattering pattern of the finite array is then computed approximately by integrating the infinite periodic array currents over the extent of the given finite array. Numerical results are presented for the infinite and finite arrays, and the accuracy of the approximate solution for the finite array is examined.