Investigation On The Band-pass Filters By Using Cavity-loaded Dielectric Resonators In A Substrate Integrated Waveguide

More and more attention has been applied to the high performance and compact sizepassive components as the rapid development of wireless communication system in thepast three decades. A dielectric resonator placed in the metal waveguide, works at singlemode in conventional dielectric resonator filter, which is large and heavy. In this paper, anovel resonator structure using dielectric resonator embedded into substrate integratedwaveguide is proposed. It has the advantages of dielectric resonator and SIW, planarstructure, reduced volume with three modes in one cavity, compact size, easily integratedwith other circuits.This work can be summarized as follows:（1）For the first time to propose a novel resonator structure with a substrateintegrated waveguide loaded ring dielectric resonators, and get the analytical formula ofthe resonant frequency of TMmn0mode, and calculate the Q-factor of TM010and TM110mode.（2）Introduce new exciting and coupling structure, using the resonant structureproposed, a three-pole filter is designed, simulated, fabricated and measured. Then studythe problem of tuning, spurious suppression, source and load coupling, tolerance analysisand return loss degeneration.（3）Design the coupling structure between two SIW cavities, simulated, fabricatedand measured the six-pole band-pass filter using two SIW cavities loaded ring dielectricresonator. Introduce the tuning elements and source and load coupling to improve theperformance of the filter.