CAD-oriented analysis of cylindrical and spherical dielectric resonators in cavities and MIC environments by means of finite elements

Cylindrical dielectric resonators (DRs) have been very useful to microwave engineers in the design and manufacture of many devices and communication systems. New dielectric materials and shapes are tested in order to improve the response of these devices. At high frequency, the miniaturization of components, together with the need to establish the resonant frequencies and field distributions accurately, recommends the use of geometrically flexible and reliable numerical methods as the finite element method (FEM). In this study, a code based in the axisymmetric FEM is implemented. A semi-automatic mesher and postprocessing modules allow resonant frequencies, field distributions, and the Q-factor to be obtained by changing the shape or the properties of the material in a reliable way. Some classic cylindrical DRs are reviewed, and new geometries such as spherical and hemispherical shapes on substrates are also studied.