Ultra-Wideband Bandpass Filter Based on Parallel-Coupled Microstrip Lines and Defected Ground Structure
Keywords:
Bandpass filter, coupled microstrip lines, defected ground structure (DGS), folded stepped-impedance stubAbstract
A compact planar microstrip bandpass filter with 3.1 GHz ? 10.6 GHz bandwidth, below 1 dB in-band insertion loss, 0.2 ns ? 0.6 ns group delay and out-of-band rejection level better than - 10 dB is presented for ultra-wideband (UWB) applications. The desired UWB is realized by etching a defected ground structure (DGS) in the ground plane and loading a folded steppedimpedance stub by one of the coupling microstrip lines. This can offer two transmission zeros at lower and upper edges of the passband, which improve the passband selectivity and out-of-band rejection significantly. An equivalent lumped circuit model is introduced; the result of the circuit model fits the EM model well. The simulated and measured results are in good agreement
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References
FCC, “Revision of part 15 of the commission’s rules regarding ultra-wideband transmission systems,” Tech. Rep., ET-Docket 98-153, FCC02- 48, April 2002.
L. Zhu, S. Sun, and W. Menzel, “Ultra-wideband (UWB) bandpass filter using multiple-mode resonator,” IEEE Microw. Wirel. Compon. Lett., vol. 15, no. 11, pp. 796-798, 2005.
K. Wu and X. Zhang, “Development of packaged ultra-wideband bandpass filters,” IEEE Trans. Microw. Theory Tech., vol. 58, pp. 220-228, Jan. 2010.
F. Karshenas, A. R. Mallahzadeh, and J. Rashedmohassel, “Size reduction and harmonic suppression of parallel coupled line bandpass filters using defected ground structure,” Appl. Comp. Electro. Soc. (ACES) Journal, vol. 25, no. 2, pp. 149-155, Feb. 2010.
M. Al Sharkawy, A.Boutejdar, F. Alhefnawi, and O. Luxor, “Improvement of compactness of lowpass/bandpass filter using a new electromagnetic coupled crescent defected ground structure resonators,” Appl. Comp. Electro. Soc. (ACES) Journal, vol. 25, no. 7, pp. 570-577, July 2010.
U. Sajjad and A. Sheta, “Compact bandpass filters with bandwidth control using defected ground structure (DGS),” Appl. Comp. Electro. Soc. (ACES) Journal, vol. 26, no. 7, pp. 624-630, July 2011.
W. Shao, J.-L. Li, “Accurate modeling of a patterned ground and its application to microwave filters,” Appl. Comp. Electro. Soc. (ACES) Journal, vol. 27, no. 7, pp. 596-602, July 2012.
L. Zhu, S. Sun, and W. Menzel, “Ultra-wideband (UWB) band-pass filter with hybrid microstrip / CPW structure,” IEEE Microw. Wirel. Compon. Lett., vol. 15, no. 12, pp. 844-846, 2005.
L. Zhu and W. Menzel, “Compact microtrip bandpass filter with two transmission zeros using a stub-tapped half-wavelength line resonator,” IEEE Microw. Wirel. Compon. Lett., vol. 10, no. 1, pp. 16–18, 2003.
