Analysis of Finite Large Phased Arrays of Waveguides by the Mode Matching/Finite Element and a Spectral Decomposition Approach

A novel hybrid Mode Matching/Finite Element/Spectral Decomposition (MM/FE/SD) approach is applied to the analysis of finite but large arrays. The proposed technique combines the numerical efficiency of the MM procedure and the versatility of the FE method with the capability of the SD to handle the finite problem. In particular, the MM/FE method is employed to obtain the Generalized Scattering Matrix (GSM) of the single unit cell of the infinite phased array. The SD allows us to solve the finite large problem as a summation of infinite periodic problems through a Discrete Fourier Transform (DFT) approach. The methodology is here extended to deal with arbitrarily oriented directions (three-dimensional problems), by taking into account also the depolarization effects.