Title :
Dual-Band Coaxial Cavity Bandpass Filter With Helical Feeding Structure and Mixed Coupling
Author :
Fu-Chang Chen ; Jie-Ming Qiu ; Sai-Wai Wong ; Qing-Xin Chu
Author_Institution :
Sch. of Electron. & Inf. Eng., South China Univ. of Technol., Guangzhou, China
Abstract :
In this letter, stepped-impedance resonators are used in coaxial cavity filter to generate dual-band response. Two key merits of the proposed filter are the helical feeding structure and the introduction of mixed coupling for coupling control and generation of transmission zero. The helical feeding structure makes it possible to conveniently control the external quality factors of two bands. To illustrate the concept, a third-order dual-band coaxial cavity filter is designed, fabricated and measured. The measured results are in good agreement with the full-wave simulation results.
Keywords :
Q-factor; band-pass filters; cavity resonator filters; helical waveguides; waveguide filters; coupling control; dual-band coaxial cavity bandpass filter; dual-band response; helical feeding structure; mixed coupling; quality factors; stepped-impedance resonators; transmission zero; Band-pass filters; Cavity resonators; Couplings; Dual band; Filtering theory; Magnetic resonance; Passband; Bandpass filter (BPF); coaxial cavity; dual-band filter; helical feeding structure; stepped-impedance resonator;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2014.2369965
