High Selectivity Balanced Filters Based on Transversal Signal-interaction Concepts
Keywords:
Balanced filter, differential/common mode, open/shorted coupled lines, transmission zeros, transversal signal-interaction conceptsAbstract
Two novel high selectivity balanced filters based on transversal signal-interaction concepts with wideband common mode suppression are proposed in this paper. Four and six transmission zeros near each passband are realized to improve the selectivity for the differential mode. In addition, the common mode can be suppressed with insertion loss greater than 15 dB over a wide frequency band. Two prototypes (?r = 2.65, h = 0.5 mm, tan ? = 0.003) with 3-dB fractional bandwidths of 31.3% and 32% for the differential mode with upper stopband greater than 18 dB are designed and fabricated. Good agreements can be observed between measured results and theoretical expectations.
Downloads
References
F. Broydé and E. Clavelier, “Crosstalk in balanced interconnections used for differential signal transmission,” IEEE Trans. Circuits Syst. I, Reg. Papers, vol. 54, no. 7, pp. 1562-1572, July 2007.
T. B. Lim and L. Zhu, “A differential-mode wideband bandpass filter on microstrip line for UWB application,” IEEE Microw. Wirel. Compon. Lett., vol. 19, no. 10, pp. 632-634, Oct. 2009.
X. H. Wang, Q. Xue, and W. W. Choi, “A novel ultra-wideband differential filter based on doublesided parallel-strip line,” IEEE Microw. Wireless Compon. Lett., vol. 20, no. 8, pp. 471-473, Oct. 2010.
H. T. Zhu, W. J. Feng, W. Q. Che, and Q. Xue, “Ultra-wideband differential bandpass filter based on transversal signal-interference concept,” Electron. Lett., vol. 47, no. 18, pp. 1033-1035, Sep. 2011.
J. Shi, C. Shao, J. X. Chen, Q. Y. Lu, Y. J. Peng, and Z. H. Bao, “Compact low-loss wideband differential bandpass filter with high common mode suppression,” IEEE Microw. Wireless Compon. Lett., vol. 23, no. 9, pp. 480-482, Sep. 2013.
W. J. Feng and W. Q. Che, “Novel wideband differential bandpass filters based on T-shaped structure,” IEEE Trans. Microw. Theory Tech., vol. 60, no. 6, pp. 1560-1568, June 2012.
W. J. Feng, W. Q. Che, and Q. Xue, “Balanced filters with wideband common mode suppression using dual-mode ring resonators,” IEEE Trans. Circuits Syst. I, vol. 62, no. 6, pp. 1499-1507, June 2015.
L. L. Qiu and Q. X. Chu, “Balanced bandpass filter using stub-loaded ring resonator and loaded coupled feed-line,” IEEE Microw. Wireless Compon. Lett., vol. 25, no. 10, pp. 654-656, Oct. 2015.
Q. Y. Lu, J.-X. Chen, L.-H. Zhou, and H. Tang, “Novel varactor-tuned balanced bandpass filter with continuously high common-mode suppression,” ACES Jour., vol. 28, no. 7, pp. 628-632, July 2013.
Q. Xiao, C. X. Zhou, “Design of balanced SIW filter with transmission zeroes and linear phase,” ACES Jour., vol. 30, no. 9, pp. 1019-1023, Sep. 2015.
W. J. Feng, X. Gao, W. Q. Che, W. C. Yang, and Q. Xue, “High selectivity wideband balanced filters with multiple transmission zeros,” IEEE Trans. Circuits Syst. II, vol. PP, no. 99, pp. 1-1, May 2015.
X. H. Wang, S. Hu, and Q. Y. Cao, “Differential broadband filter based on microstrip coupled line structures,” Electron. Lett., vol. 50, no. 15, pp. 1069-1070, July 2014.
W. J. Feng, W. Q. Che, and Q. Xue, “Transversal signal interaction: Overview of high-performance wideband bandpass filters,” IEEE Microw. Magazine, vol. 15, no. 2, pp. 84-96, Mar. 2014.
