A Filtering Power Divider with Wide Bandwidth Using a Single dielectric-loaded Cavity Resonator

This paper presents a novel wideband filtering power divider based on a multi-mode dielectric-loaded cylindrical cavity resonator. The resonator is constructed by a metal-embedded cylindrical dielectric disk loaded at the center of a cylindrical cavity, and fed by three probes with 120 -degrees displacement with each other. Three resonant modes (TM
010
, TE111 e, TE111 o) can be gathered for operation by properly tuning the lengths of feeding probes and the radius of the dielectric disk. Two transmission zeros can be respectively generated at the upper and lower stopband. For demonstration, a prototype operating at 3.5 GHz was designed, fabricated, and measured. A good agreement between the simulation and measurement can be observed. The measured results suggest a wide fractional bandwidth of 33.3%.