Conclusion
Dielectric resonators - Microwave circuits

The dielectric resonator confines electromagnetic energy to 95% according to the TE resonance mode_01δ. Characterization in this mode, as a resonant cavity in resonant frequency and quality coefficient, is a method for tracing the value of the material's dielectric tangent. Low values, less than 10^–4, can be measured conveniently and inexpensively for dielectric permittivities typically above 20. Details of the characterization of other material properties, such as permittivity and thermal stability, as well as the dielectric loss tangent for permittivities below 20, can be found in [E1922],.