A Miniaturized LPF with Sharp Transition-band Using Semi-circle Resonators
Keywords:
L-band, LPF, open stub, semi-circle resonator, sharp transition-bandAbstract
In this paper, a miniaturized microstrip low-pass filter (LPF) with sharp transition-band, wide stop-band and negligible insertion-loss in pass-band is proposed using semi-circle and butterfly resonators. The cutoff frequency of the proposed LPF is 1.75 GHz. The proposed LPF presents a wide stop-band from 2.1 to 23.73 GHz (2nd-14th harmonics) with -20 dB attenuation level. The overall dimension of the proposed filter is 0.11?g × 0.1?g. The sharpness of transition-band is 112 dB/GHz, from 1.75 to 2.26 GHz with corresponding attenuation levels of -3 dB and -60 dB, respectively. The insertion-loss in pass-band is less than 0.05 dB. The proposed LPF is simulated, fabricated and measured, which there is a good agreement between the results of simulation and measurement. The LPF has been designed for L-band applications.
Downloads
References
D. M. Pozar, Microwave Engineering. John Wiley & Sons, New York, 2005.
J. S. Hong and M. J. Lancaster, Microstrip Filters for RF/Microwave Applications. John Wiley & Sons, New York, 2001.
Y. Zhang, L. Jin, and L. Li, “Design of LPF using Hi-Lo interdigital DGS slot,” IEICE Electronics Express, vol. 13, no. 9, pp. 1-6, 2016.
L. Li, Z. F. Li, and J. F. Mao, “Compact lowpass filters with sharp and expanded stopband using stepped impedance hairpin units,” IEEE Microwave and Wireless Components Letters, vol. 20, no. 6, pp. 310-312, 2010.
J. P. Wang, L. Ge, Y. X. Guo, and W. Wu, “Miniaturised microstrip lowpass filter with broad stopband and sharp roll-off,” Electronics Letters, vol. 46, no. 8, pp. 573-575, 2010.
L. Shuai, J. Xu, and Z. Xu, “Compact lowpass filter with wide stopband using stepped impedance hairpin units,” Electronics Letters, vol. 51, no. 1, pp. 67-69, 2014.
F. Wei, L. Chen, and X. W. Shi, “Compact lowpass filter based on coupled-line hairpin unit,”Electronics Letters, vol. 48, no. 7, pp. 379-381, 2012.
V. Velidi and S. Sanyal, “Sharp roll-off lowpass filter with wide stopband using stub-loaded coupled-line hairpin unit,” IEEE Microwave and Wireless Components Letters, vol. 21, no. 6, pp. 301-303, 2011.
F. Wei, L. Chen, X. W. Shi, Q. L. Huang, and X. H. Wang, “Compact lowpass filter with wide stopband using coupled-line hairpin unit,” Electronics Letters, vol. 46, no. 1, pp. 88-90, 2010.
X. B. Wei, P. Wang, M. Q. Liu, and Y. Shi, “Compact wide-stopband lowpass filter using stepped impedance hairpin resonator with radial stubs,” Electronics Letters, vol. 47, no. 15, pp. 862- 863, 2011.
M. Rezaei Khezelia, M. Hayati, and A. Lotfi, “Compact wide stopband lowpass filter using spiral loaded tapered compact microstrip resonator cell,” International Journal of Electronics, vol. 101, no. 3, pp. 375-382, 2012.
C. J. Chen, “Design of artificial transmission line and low-pass filter based on aperiodic stubs on a microstrip line,” IEEE Transaction on Components, Packing and Manufacturing Technology, vol. 4, no. 5, pp. 922-928, 2014.
Q. Li, Y. Zhang, and Y. Fan, “Compact ultra-wide stopband low pass filter using multimode resonators,” Electronics Letters, vol. 51, no. 14, pp. 1084-1085, 2015.
F. C. Chen, H. T. Hu, J. M. Qiu, and Q. X. Chu, “High-selectivity low-pass filters with ultrawide stopband based on defected ground structures,” IEEE Transaction on Components, Packing and Manufacturing Technology, vol. 5, no. 9, pp. 1313- 1319, 2015.
A. K. Verma, N. P. Chaudhari, and A. Kumar, “High performance microstrip transverse resonance lowpass filter,” Microwave and Optical Technology Letters, vol. 55, no. 5, pp. 1149-1152, 2013.
P. Zhang, M. Li, and J. Wang, “Miniaturized lowpass filter with ultra-wide stopband using dualplan defected structures,” IEICE Electronics Express, vol. 12, no. 2, pp. 1-7, 2014.
