Dielectric Combline Resonators and FiltersIEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 46, NO. 12, DECEMBER 1998 2501 Dielectric Combline Resonators and Filters Chi Wang, Senior Member, IEEE, Kawthar A. Zaki, Fellow, IEEE, Ali E. Atia, Fellow, IEEE, and Tim G. Dolan Abstract―The dielectric combline resonator combines the merits of the metallic combline and dielectric loaded resonator. By replacing the inner conductor of the conventional combline resonator by a high r dielectric rod, higher unloaded Q can be expected. Resonant frequency, unloaded Q, and coupling coefcient of the resonator are obtained by a rigorous mode-matching method. An eight-pole elliptic-function dielectric combline resonator lter was designed and tested. Measured frequency responses verify the theory. Index Terms― Combline resonator, dielectr……