A compact ultra-wideband (UWB) bandpass filter (BPF) with improved harmonic suppression using a modified coupling structure is presented in this paper. The modified coupling structure is constructed by taper-connecting two folded open stubs to the traditional parallel-coupled lines, which shows an improved characteristic in harmonic suppression. By integrating the proposed coupling and the stepped-impedance stub loaded resonator (SISLR), a UWB BPF is finally built and tested. The simulated and measured results are in good agreement with each other, exhibiting good wideband filtering characteristic and improved out-of-band performance.
2. Hsu, C. L., F. C. Hsu, and J. T. Kuo, "Microstrip bandpass filters for ultra-wideband (UWB) wireless communications," IEEE MTT-S Int. Symp. Dig., 679-682, Jun. 2005.
3. Ji, M. Z. and Q. X. Chu, "A compact UWB bandpass filter using pseudo-interdigital stepped impedance resonators," Proc. China Microwave Millimeter-wave Conference, 1096-1098, Ningbo, China, Oct. 2007.
doi:10.1109/LMWC.2005.859011
4. Zhu, L., S. Sun, and W. Menzel, "Ultra-wideband (UWB) bandpass filter using multiple-mode resonator," IEEE Microwave Wireless Components Letters, Vol. 15, No. 11, 796-798, 2005.
doi:10.1163/156939308784150317
5. Gao, S. S., et al., "Compact ultra-wideband (UWB) bandpass filter using modified stepped impedance resonator," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 4, 541-548, 2008.
doi:10.1109/LMWC.2010.2053024
6. Chu, Q. X. and X. K. Tian, "Design of UWB bandpass filter using stepped-impedance stub loaded resonator," IEEE Microwave Wireless Components Letters, Vol. 20, No. 9, 501-503, 2010.
doi:10.2528/PIER07082302
7. Chen, H. and Y. X. Zhang, "A novel and compact UWB bandpass filter using microstrip fork-form resonator," Progress In Electromagnetics Research, Vol. 77, 273-280, 2007.
doi:10.2528/PIERL08121309
8. An, J., G.-M. Wang, W. D. Zeng, and L.-X. Ma, "UWB filter using defected ground structure of Von Koch fractal shape slot," Progress In Electromagnetics Research Letters, Vol. 6, 61-66, 2009.
doi:10.1163/156939308787537982
9. Gong, J. Q. and Q. X. Chu, "SCRLH TL based UWB bandpass filter with widened upper stopband," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 14-15, 1985-1992, 2008.
doi:10.2528/PIER10070403
10. Huang, J. Q. and Q. X. Chu, "Compact UWB band-pass filter utilizing modified composite right/left-handed structure with cross coupling," Progress In Electromagnetics Research, Vol. 107, 179-186, 2010.
doi:10.1163/156939308784158661
11. Gao, S. S., S. Q. Xiao, J. P. Wang, X. S. Yang, Y. X. Wang, and B. X. Wang, "Compact UWB bandpass filter with wide stopband," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 8-9, 1043-1049, 2008.
doi:10.1163/156939308786375118
12. Wei, F., P. Chen, L. Chen, and X. W. Shi, "Design of a compact UWB bandpass filter with defected ground structure," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 13, 1783-1790, 2008.
doi:10.1109/LMWC.2010.2047469
13. Lee, J. K. and Y. S. Kim, "Ultra-wideband bandpass filter with improved using defected ground structure," IEEE Microwave Wireless Components Letters, Vol. 20, No. 6, 316-318, 2010.
doi:10.1109/LMWC.2007.897788
14. Wong, S. W. and L. Zhu, "EBG-embedded multiple-mode resonator for UWB bandpass filter with improved upper-stopband performance," IEEE Microwave Wireless Components Letters, Vol. 17, No. 6, 421-423, 2007.
doi:10.1109/LMWC.2006.887251
15. Li, R. and L. Zhu, "Compact UWB bandpass filter using stub-loaded multiple-mode resonator," IEEE Microwave. Wireless Components Letters, Vol. 17, No. 1, 40-42, 2007.
doi:10.1049/el:20080789
16. Chu, Q. X. and S. T. Li, "Compact UWB bandpass filter with improved upper-stopband performance," Electronics Letters, Vol. 44, No. 12, 742-743, 2008.
doi:10.1049/el:20072094
17. Lim, T. B., S. Sun, and L. Zhu, "Compact ultra-wideband band-pass filter using harmonic-suppressed multiple-mode resonator," Electronics Letters, Vol. 43, No. 22, 1205-1206, 2007.
doi:10.1109/LMWC.2008.2008558
18. Yao, B. Y., et al., "Compact UWB bandpass filter with improved upper-stopband performance," IEEE Microwave Wireless Components Letters, Vol. 19, No. 1, 27-29, 2009.
doi:10.1109/LMWC.2006.879492
19. Sun, S. and L. Zhu, "Capacitive-ended interdigital coupled lines for UWB bandpass filters with improved out-of-band performances," IEEE Microwave Wireless Components Letters, Vol. 16, No. 8, 440-442, 2006.
20. Chu, Q. X. and X. K. Tian, "Design of UWB bandpass filter with notched band," Proc. Asia-Pacific Microwave Conference, 37-40, 2010.
Submit
