Input admittance of a coaxial-line-driven cylindrical cavity with a center dielectric rod

An expression for the input admittance of a coaxially driven cylindrical cavity is presented. Two cases are presented: first, where the coaxial-line transition is located on one of the flat walls of an empty cavity, and secondly where there is a dielectric rod located coaxially between the two flat walls of the cavity. A comparison between the theory and measurements is presented which shows that the model is capable of yielding a high level of accuracy.