Analysis of multilayer printed arrays by a modular approach based on the generalized scattering matrix

In this paper, a modular technique is used to treat infinite multilayer printed arrays with apertures and patches of irregular shapes. Each array layer is characterized by a generalized scattering matrix (GSM) from which the overall GSM of the multilayer structure is computed. The excitation of each element is modeled as a transition from the microstrip line to an aperture in the ground plane. The GSM of this transition is computed using the reciprocity theorem and spectral domain moment method. Several arrays have been analyzed by the proposed technique and the numerical results are in good agreement with other theoretical and experimental data