A versatile prototype for the accurate design of homogeneous and inhomogeneous wide bandwidth direct-coupled-cavity filters

In this paper, a new and very versatile prototype for the design of both homogeneous and inhomogeneous wideband direct-coupled-cavity filters is presented. The prototype provides a high flexibility to accurately represent the frequency dependence of the real waveguide components that compose the structure. An approximate synthesis procedure is also described. Several application examples are studied, and the results prove the advantages of the new approach over the techniques conventionally used in the design of this type of filters.