Accelerated full-wave analysis of a 2D periodic array of rectangular patches excited by a 1D array of sources

The full-wave analysis of periodic structures requires appropriate techniques to enhance the computational efficiency of the adopted numerical algorithms. Many strategies have been proposed to this aim so far (acceleration and sampling of Green´s functions, treatment of the relevant matrix elements, spatial- and spectral- domain approaches, etc.). In this paper we address the efficient analysis of a simple periodic geometry: a bidimensional array of rectangular patches. A very fast algorithm is needed with the aim to study the nonperiodic excitation of this structure through the array scanning method (ASM) [B.A. Munk and G.A. Burrell, 1979]. In fact, the ASM reduces the nonperiodic problem to an integral superposition of auxiliary Floquet-periodic problems; the integration is performed over the phase shifts between adjacent spatial periods (unit cells) of the structure and requires the numerical solution of a large number of periodic problems.