Title :
Control of attenuation pole frequency of a dual-mode microstrip ring resonator bandpass filter
Author :
Kundu, Arun Chandra ; Awai, Ikuo
Author_Institution :
Telecom Technol. Dev. Center, TDK Corp., Chiba, Japan
fDate :
6/1/2001 12:00:00 AM
Abstract :
A novel method is proposed to control the attenuation pole frequency of a dual-mode circular microstrip ring resonator bandpass filter, keeping the bandwidth constant. In this paper, the coupling between the dual modes is provided as the total effect of stub perturbation at the end of symmetry plane, and the angle between input/output ports. By making a various combinations of these two parameters, it is possible to control the attenuation pole frequency. An additional small coupling induced by excitation capacitance is also considered. Filters are simulated using the calculated coupling constant, and then the attenuation pole frequencies and bandwidth of the simulated filters are verified by experiment. Theoretical expressions are further devised to calculate the attenuation pole frequencies
Keywords :
band-pass filters; frequency control; microstrip filters; microstrip resonators; poles and zeros; resonator filters; attenuation pole frequency control; bandwidth; coupling constant; dual-mode microstrip ring resonator bandpass filter; excitation capacitance; stub perturbation; Attenuation; Band pass filters; Bandwidth; Coupling circuits; Frequency; Microstrip filters; Microstrip resonators; Microwave filters; Optical ring resonators; Resonator filters;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
