Quasi dual-mode resonators

The paper discusses the concept of using two single-mode resonators to construct a quasi dual-mode resonator that has all the features of traditional dual-mode resonators. Two novel filter structures are presented in this paper that employs this concept; one employs planar type resonators and the other employs dielectric resonators. A new configuration for a single mode dielectric resonator is also proposed in this paper. The use of such type of resonators makes it possible to construct dielectric resonator filters that are much smaller in size than conventional TE/sub 01/ single mode resonators. Measured and theoretical results are presented to verify the concepts proposed in this paper.