A New Approach to Interacting Discontinuities in Planar Dielectric Waveguides

Planar dielectric waveguides are important in electro-optics and at millimeter frequencies. In many integrated optical components grooves are etched and overlays are deposited on the planar surface. Corrugations are used in antenna feeds and in various dielectric slow wave structures in millimeter wave devices. Cascades of step discontinuities are idealizations of such structures. In this contribution a novel and fundamental approach to their analysis is presented. This is electromagnetically rigorous and, as such, capable of accounting for the interaction between adjacent and not adjacent discontinuities. Moreover, for the first time, the resonant behaviour and hence the frequency dependence, of such structures is explicitly described.