Cavity modes
Dielectric resonators - Microwave circuits

The cavity modes near the resonance peak of the TE mode _01δ are distinguished by the fact that they appear as soon as the shield is closed. These peaks constitute spurious modes for the mode in question. In fact, these modes can be used in filter applications. Their analysis has been performed  , these can be correlated with the empty-cavity modes by including a partial dielectric load. Figure