TEM mode
Dielectric resonators - Microwave circuits

The term "dielectric resonator" is also applied to metallized tubular ceramics, which are used to create coaxial resonators (Figure18). The cross-section of the tube can be square, which facilitates flat mounting on a substrate, as shown in Figure19. The resonance modes are of the TEM type, with field lines as shown in Figure18. This type of resonator is used when insertion losses are less critical than volume reduction; the volume for a given frequency is smaller than for TE-mode resonators_01δ. This type...