Electromagnetic scattering of large finite arrays of patch antennas

We develop CG-FFT method based on multilevel block-Toeplitz matrices to analyse the scattering of a large finite array of patch antennas. In our approach, the sub-domains are divided only on the patches´ surface. The rooftop basis function and Galerkin´s method are applied to discretize the mixed potential integral equation (MPIE) and establish a matrix equation. The impedance matrix is consisted of four 4-level block-Toeplitz matrices. The matrix equation is solved by using the CG method, where the matrix-vector multiplications are performed by using 4-dimensional FFTs. The numerical results including current distribution on a patch antenna and RCS of a patch antenna array are verified. The RCS of 32×32 and 64×64 microstrip patch antenna arrays are presented.