Abstract
A microstrip interlocked-coupled bandpass filter is proposed with a markedly compact structure. The low-impedance open-end line of the quarter-wavelength Stepped-Impedance Resonator (SIR) is replaced by two open-end high-impedance lines, which not only facilitate the coupling mechanism but also provide the strong electric coupling between resonators. With the proper utilization of folded SIRs, the occupied area of coupled-resonator pair can be reduced. By applying the proposed coupled-resonator pair, the passband filter with the compact size can be realized. Good agreement between measured and simulated results is observed. The proposed filter is desirable for compact and high-performance microwave circuit applications.
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References
H. W. Liu and W. M. Li. Miniaturised microstrip bandpass filter using octagonal hairpin resonators with side-coupled technique. Electronics Letters, 44(2008)24, 1410–1411.
K. Ma, K. S. Yeo, J. Ma, et al. An ultra-compact hairpin band pass filter with additional zero points. IEEE Microwave and Wireless Components Letters, 17(2007)4, 262–264.
Q. X. Chu and H. Wang. A compact open-loop filter with mixed electric and magnetic coupling. IEEE Transactions on Microwave Theory and Techniques, 56(2008)2, 431–439.
J. L. Li, J. X. Chen, W. Shao, et al. Miniaturised microstrip bandpass filter using stepped impedance ring resonators. Electronics Letters, 40(2004)22, 1420–1421.
C. H. Liang, C. H. Chen, and C. Y. Chang. Fabrication-tolerant microstrip quarter-wave stepped-impedance resonator filter. IEEE Transactions on Mi crowave Theory and Techniques, 57(2009)5, 1163–1172.
S. C. Lin, Y. S. Lin, and C. H. Chen. Miniaturized microstrip interlocked-coupled bandpass filters using folded quarter-wavelength resonators. Proceedings of Asia-Pacific Microwave Conference, Yokohama, Japan, Dec. 2006, 1427–1430.
C. H. Liang, W. S. Chang, and C. Y. Chang. Compact microstrip bandpass filters using miniaturized quarter-wavelength resonators. Proceedings of Asia-Pacific Microwave Conference, Yokohama, Japan, Dec. 2010, 263–266.
T. Yang, R. Xu, L. Xia, and Y. Guo. A novel compact microstrip bandpass filter using folded stepped impedance resonators. Microwave and Optical Technology Letters, 50(2008)7, 1864–1867.
M. Makimoto and S. Yamashita. Microwave Resonator and Filters for Wireless Communication: Theory, Design, and Application. Kawasaki 214, Japan, Matsushita Research Institute Tokyo, Inc., 2000, 11–16.
J. S. Hong and M. J. Lancaster. Microstrip Filter for RF/Microwave Applications. New York, John Wiley & Sons, Inc., 2001, 235–271.
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Communication author: Chen Chunhong, born in 1978, male, Master Degree.
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Chen, C., Wu, W. & Wu, H. Compact interlocked-coupled filter using folded stepped-impedance resonators. J. Electron.(China) 29, 137–141 (2012). https://doi.org/10.1007/s11767-012-0807-x
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DOI: https://doi.org/10.1007/s11767-012-0807-x