Modeling Microwave Waveguide Components: The Tuned Stub
The waveguide device modeled here specifically demonstrates the exploration of a small, but very important, subset of components of the family of microwave hardware devices designed to facilitate the optimized transfer of power from the generating source to the consuming load. Each of those components is called, in electronics terminology, a Tuned Stub.
A stub is a length of transmission line or waveguide that is connected to the active circuit at one end only. This paper models a rectangular waveguide with three adjustable stubs distributed along the upper surface of the waveguide. The waveguide stubs are hollow, as is the waveguide, and they are each electromagnetically connected to the inner cavity, at right angles to the central axis of the waveguide via an aperture in the wall of the waveguide. In this case, three (3) stubs have been added along the length of the waveguide to optimize the tuning performance.