Two-mode bandpass filter using open stub loaded resonator

Tao LEI; Tianyu XIANG; Anjiang LU; Man PENG; Zhengping ZHANG

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Journal of Tsinghua University(Science and Technology) ›› 2014, Vol. 54 ›› Issue (1) : 84-87.

Orginal Article

Two-mode bandpass filter using open stub loaded resonator

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Abstract

Having the advantages of compact sizes, high Qs and low radiation losses, square ring resonators have been widely used to design filters, mixers, oscillators, and antennas. A stub-loaded ring resonator was developed to design dual-mode filters. The developed dual-mode resonator was found to have the advantage that the even-mode resonant frequencies can be flexibly controlled whereas the odd-mode resonant frequencies are fixed. Stepped impedance line is adopted to achieve strong coupling between the input/output (I/O) and the resonator, increasing the bandwidth of the filter. The center frequency of the new filter is 4.97GHz, with the minimum insertion of 1.33dB in passband and the 3dB fractional bandwidth of 9.38%. The results also show that the filter possesses a quasi-elliptic response which improves the stopband rejection.

Key words

two-mode filter / square ring resonator / open stub / stepped impedance line

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Tao LEI, Tianyu XIANG, Anjiang LU, Man PENG, Zhengping ZHANG. Two-mode bandpass filter using open stub loaded resonator[J]. Journal of Tsinghua University(Science and Technology). 2014, 54(1): 84-87

References

[1]	HONG Jiasheng, LI Shuzhou. Theory and experiment of dual-mode microstrip triangular patch resonators and filters [J]. Transactions on Microwave Theory and Techniques, 2004, 52(4): 1237-1243.
[2]	CHEN Chuyu, HSU Chengying, LIN SungFong. A novel compact miniaturized wideband microstrip bandpass filters with dual-mode ring resonators[J]. Microwave and Optical Technology Letters, 2005, 45(4): 312-315.
[3]	CHOI ByungChang, LEE WuSeong, KIM HaChu, et al.A dual-band bandpass filter using a dual-mode ring resonator with two short-circuited stubs [C]//MMS. Ankara, Turkey, 2010: 152-155.
[4]	Wolff I. Microstrip bandpass filter using degenerate modes of a microstrip ring resonator[J].Electronics Letters, 1972, 8(12): 302-303.
[5]	Hsieh L H, Chang K. Compact, low insertion loss, sharp rejection wideband bandpass filters using dual-mode ring resonators with tuning stubs[J]. Electronics Letters, 2001, 37(22): 1345-1346.
[6]	HONG Jiasheng, Hussein S, CHUN Younghoon. Dual-mode microstrip open-loop resonators and filters[J]. Transactions on Microwave Theory and Techniques, 2007, 55(8): 1764-1770.
[7]	WANG Lang, LIU Hanli, WEI Joshua Le-LI. Novel UWB bandpass filter using multiple-mode resonator units in series [C] // iWEM. Chengdu, China, 2012: 1-3.
[8]	ZHANG Xiuyin, CHEN Jianxin, XUE Quan, et al.Novel dual-band bandpass filters using stub-loaded short-ended resonators[J]. IEEE Microwave and Wireless Components Letters, 2007, 17(8): 583-585.
[9]	ZHU Lei, SUN Sheng, Wolfgang M. Ultra-wideband (UWB) bandpass filters using multiple-mode resonator[J]. Microwave and Wireless Components Letters, 2005, 15(11): 796-798.
[10]	CHU Qingxin, WU Xiaohu, TIAN Xukun. Novel UWB bandpass filter using stub-loaded multiple-mode resonator[J]. Microwave and Wireless Components Letters, 2011, 21(8): 403-405.