Accurate Analysis of Dielectric Backed Planar Conducting Layers of Arbitrarily Shaped in a Rectangular Waveguide

The characteristics of dielectric backed planar conducting layers of arbitrarily shaped in a rectangular waveguide are calculated by means of coupled integral equation technique (CIET) which accurately takes higher order mode interactions. Equivalent structures for the accurate analysis whole structure are introduced in which magnetic surface currents are identified as the unknowns at the aperture parts of interfaces in all regions. Spectral dyadic green’s functions are derived for these equivalent structures. A coupled magnetic filed integral equation formulation is proposed which is solved using method of moment (MoM). Then one matrix equation that involves the all magnetic currents of non metallic parts (aperture parts) of discontinuities is derived. This single matrix formulation replaces the procedure of cascading individual GSM’s of each block. By dividing the area of cross section in discontinuities into a given number of subsections, it is possible to model any shape of metallic parts. In this method when the shape of metallic parts (in a given structure) changes, the related coupled integral equations can be extracted from the pre-computed general matrices in a given frequency and there is not need to repeat the all of process. The proposed technique permits modeling of a variety of structures such as cavity-backed micro strip antenna, frequency selective surfaces (FSS’s), waveguide filters with printed irises and generally multilayered media with printed circuits embedded between dielectric layers in a waveguide. The usefulness of the proposed method and its performance are verified by calculating and simulating of a given structure.