Guided wave propagation on two-dimensional clusters of directly-coupled cavity resonators

An attempt is made to determine the guided-wave propagation properties of electrically large, two-dimensional delay structures, composed of clusters of directly coupled, high-Q cavity resonators, ordered in either a square or in a hexagonal lattice. The approach used considers the unit-cells as linear reciprocal multiport networks, exhibiting either C/sub 4V/-symmetry or C/sub 6V/-symmetry, consistent with either the square-lattice or the hexagonal-lattice ordering of the unit cells. The image-transfer-function matrix of a single unit-cell uniquely determines the dispersion characteristics of the delay structure within any given passband; the guided-wave attenuation, a function of frequency, within any given stopband; and the natural port-modes of the unit-cell (defined by the eigenvectors of the image-transfer-function matrix).<>