Eigenmodes of a periodic array of coupled waveguides

Abstract

General properties of eigenmodes in periodic arrays of coupled waveguides are considered. The Floquet channel model is used to analyze arrays operating in the quasi-periodic mode. Relationships for the orthogonality of different types of eigenmodes are obtained on the basis of the Lorentz lemma and the active power theorem. The problem of excitation of array eigenmodes by given currents is solved. The relation between two representations of the array field, by means of the eigenmode expansion and in the form of the Fourier integral, is shown by the example of an array of coupled slot lines.