2018-12-17
High Selective and Wide-Stopband Bandpass Filter Using Simple Uniform Impedance Resonators
By
Progress In Electromagnetics Research Letters, Vol. 80, 135-141, 2018
Abstract
A fifth-order bandpass filter with high selectivity and wide-stopband by using quarter- and half-wavelength uniform impedance resonators (UIRs) is presented in this letter. The use of a terminated coupled line provides controllable transmission zeros that can suppress the parasitic passbands. A pair of transmission zeros is generated on both sides of the passband by introducing cross-coupling. As a result, high selectivity and wide stopband can be achieved simultaneously. The method of controlling transmission zeros using a coupled line and an open/short-circuited stub is analyzed, and the method of improving passband selectivity using cross-coupling is given in detais. The concept is experimentally tested in a microstrip bandpass filter with center frequency 1 GHz. The measured attenuation is better than 24 dB up to 18 GHz.
Citation
Kai-Ran Xiang, and Fu-Chang Chen, "High Selective and Wide-Stopband Bandpass Filter Using Simple Uniform Impedance Resonators," Progress In Electromagnetics Research Letters, Vol. 80, 135-141, 2018.
doi:10.2528/PIERL18102601
References

1. Kuo, T.-N., W.-C. Li, C.-H. Wang, and C. H. Chen, "Wide-stopband microstrip bandpass filters using quarter-wavelength stepped impedance resonators and bandstop embedded resonators," IEEE Microw. Wirel. Compon. Lett., Vol. 18, No. 6, 389-391, Jun. 2008.
doi:10.1109/LMWC.2008.922609        Google Scholar

2. Huang, C.-Y., M.-H. Weng, C.-S. Ye, and Y.-X. Xu, "A high band isolation and wide stopband diplexer using dual-mode stepped-impedance resonators," Progress In Electromagnetics Research, Vol. 100, 299-308, 2010.
doi:10.2528/PIER09112701        Google Scholar

3. Wu, H.-W., S.-K. Liu, M.-H. Weng, and C.-H. Hung, "Compact microstrip bandpass filter with multispurious suppression," Progress In Electromagnetics Research, Vol. 107, 21-30, 2010.
doi:10.2528/PIER10061601        Google Scholar

4. Akra, M., E. Pistono, H. Issa, A. Jrad, and P. Ferrari, "Full study of the parallel-coupled stub-loaded resonators: Synthesis method in a narrow band with an extended optimal rejection bandwidth," IEEE Trans. Microw. Theory Techn., Vol. 62, No. 12, 3380-3392, Dec. 2014.
doi:10.1109/TMTT.2014.2364599        Google Scholar

5. Tang, C., X. Q. Lin, W. M. Liu, and Y. Fan, "Wide stopband bandpass filters based on quarter-wavelength resonators," IET Microw. Antennas Propag., Vol. 11, No. 10, 1379-1388, Aug. 2017.
doi:10.1049/iet-map.2016.0785        Google Scholar

6. Chen, F. C., et al. "Design of wide-stopband bandpass filter and diplexer using uniform impedance resonators," IEEE Trans. Microw. Theory Techn., Vol. 64, No. 12, 4192-4203, Dec. 2016.
doi:10.1109/TMTT.2016.2613056        Google Scholar

7. He, Z. S., Z. H. Shao, and C. J. You, "Parallel feed bandpass filter with high selectivity and wide stopband," Electron. Lett., Vol. 52, No. 10, 844-846, May 2016.
doi:10.1049/el.2015.3345        Google Scholar

8. Weng, S.-C., K.-W. Hsu, and W.-H. Tu, "Compact and switchable dual-band bandpass filter with high selectivity and wide stopband," Electron. Lett., Vol. 49, No. 20, 1275-1277, Sep. 2017.
doi:10.1049/el.2013.2154        Google Scholar

9. Killamsetty, V. K. and B. Mukherjee, "Miniaturised highly selective bandpass filter with very wide stopband using meander coupled lines," Electron. Lett., Vol. 53, No. 13, 889-890, Jun. 2017.
doi:10.1049/el.2017.1270        Google Scholar

10. Thomas, J. B., "Cross-coupling in coaxial cavity filters - A tutorial overview," IEEE Trans. Microw. Theory Techn., Vol. 51, No. 4, 1368-1376, Apr. 2003.
doi:10.1109/TMTT.2003.809180        Google Scholar

11. Cameron, R. J., C. M. Kudsia, and R. R. Mansour, Microwave Filters for Communication Systems Fundamentals Design and Applications, Wiley, 2007.