Chen, Chi-FengChi-FengChenHuang, Ting-YiTing-YiHuangRUEY-BEEI WU2006-11-142018-07-062006-11-142018-07-06200600189480http://scholars.lib.ntu.edu.tw/handle/123456789/325314http://ntur.lib.ntu.edu.tw/bitstream/246246/200611150121366/1/368.pdfhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-33748372760&doi=10.1109%2fTMTT.2006.880653&partnerID=40&md5=1c227f98502b04a3aec6e730f1246fe9A novel method for designing multiband bandpass filters has been proposed in this paper. Coupling structures with both Chebyshev and quasi-elliptic frequency responses are presented to achieve dual- and triple-band characteristics without a significant increase in circuit size. The design concept is to add some extra coupled resonator sections in a single-circuit filter to increase the degrees of freedom in extracting coupling coefficients of a multi-band filter and, therefore, the filter is capable of realizing the specifications of coupling coefficients at all passbands. To verify the presented concept, four experimental examples of filters with a dual-band Chebyshev, triple-band Chebyshev, dual-band quasi-elliptic, and triple-band quasi-elliptic response have been designed and fabricated with microstrip technology. The measured results are in good agreement with the full-wave simulation results. © 2006 IEEE.1513073 bytesapplication/pdfzh-TWCoupling coefficient; External quality factor; Microstrip filter; Stepped-impedance resonator; Transmission zero[SDGs]SDG16Coupling coefficients; External quality factors; Microstrip filters; Stepped-impedance resonator; Transmission zero; Computer simulation; Coupled circuits; Microstrip devices; Natural frequencies; Optical resonators; Waveguide couplers; Bandpass filtersjournal article10.1109/TMTT.2006.8806532-s2.0-33748372760http://ntur.lib.ntu.edu.tw/bitstream/246246/200611150121366/1/368.pdf