Title :
Compact Bandpass Filter With Two Tunable Transmission Zeros Using Hybrid Resonators
Author :
Bin-Feng Zong ; Guang-Ming Wang ; Jian-Gang Liang ; Cheng Zhou
Author_Institution :
Lab. of Microwave Technol. & Applic., Air Force Eng. Univ., Xi´an, China
Abstract :
This letter presents a novel type of compact, low insertion loss (IL) planar microstrip filter, which is mainly composed of two hybrid resonators with a mixed electric/magnetic (EM) coupling between them. Tunable EM coupling is constructed to realize a tunable transmission zero (TZ) very close to the passband. And two folded T-shaped feed lines are adopted to introduce another tunable TZ and obtain a desired external coupling. Advantages of the proposed filter are not only its compact size and low IL, but also its tunable TZs.
Keywords :
band-pass filters; electromagnetic coupling; microstrip filters; microstrip lines; resonator filters; compact IL planar microstrip filter; compact bandpass filter; folded T-shaped feed lines; hybrid resonators; low insertion loss; mixed electricmagnetic coupling; tunable EM coupling; tunable TZ; tunable transmission zeros; Band-pass filters; Couplings; Feeds; Filtering theory; Integrated circuit modeling; Resonator filters; Wireless communication; Bandpass filter (BPF); circuit model; hybrid resonator; tunable transmission zeros;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2014.2382673
