Synthesis of symmetrical planar dielectric waveguides

The paper presents a method for synthesizing symmetrical planar microwave waveguides, based on the determination of changes of permittivity in the waveguide on the basis of the cut-off frequency spectrum for TE and TM modes. It is demonstrated that the cut-off frequency spectrum wholly defines changes in permittivity, and therefore in the dispersion of the waveguide. Attention is given to the synthesis of waveguides consisting of a dielectric film on an electric screen and a dielectric film on a magnetic screen.