An Exact Treatment of a Rectangular Waveguide Symmetrically Loaded with Resistively Coated Dielectric Slabs for Maximum Attenuation

An exact dispersion relation is presented for a waveguide with resistively-coated dielectric slabs parallel to, and against, either pair of guide walls. The current in the resistive films is assumed to be a sheet current. The accuracy of such approximations is demonstrated by measurements of insertion loss through an experimental structure. Agreement is shown to be particularly good when the surface resistance is optimum for greatest attenuation.