Image guide couplers with isotropic and anisotropic coupling elements

Among other waveguide elements directional couplers are required in integrated millimeterwave circuits in image guide technique. Hereby an I-guide is used which consists of a dielectric slab between two conducting plates on which the electric field is perpendicularily. Flat coupling behaviour and better isolation can be reached by use of a dielectric coupling element and absorber materials. Thereby the frequency dependence is reduced significantly. Further the coupling can be steered by an additional premagnetized ferrite slab. In this way switched couplers can be realized.