volume | PIER Journals

Abstract

A compact microstrip-line dual-band bandpass filter using a short stub-loaded resonator is presented. The resonator is formed by loading one short stub in shunt to a simple uniform impedance line. A key merit of the filter configuration is that the center frequency and bandwidth of the first passband can be conveniently controlled by properly adjusting the lengths of the short stubs and the coupling between the short stubs, whereas those of the second passband are fixed. To illustrate the concept, a third-order dual-band filter is designed, fabricated and measured. Simulated and measured results are found to be in good agreement with each other.

1. Chang, S. F. R., W. L. Chen, S. C. Chang, C. K. Tu, C. L. Wei, C. H. Chien, C. H. Tsai, J. Chen, and A. Chen, "A dual-band RF transceiver for multi-standard WLAN applications," IEEE Trans. Microw. Theory Tech., Vol. 53, No. 3, 1048-1055, 2005.
doi:10.1109/TMTT.2005.843509 Google Scholar

2. Alkanhal, M. A. S., "Dual-band bandpass filters using inverted stepped-impedance resonators," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 8-9, 1211-1220, 2009. Google Scholar

3. Lee, C. H., I. C. Wang, and C. I. G. Hsu, "Dual-band balanced BPF using λ/4 stepped-impedance resonators and folded feed lines," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 17-18, 2441-2449, 2009. Google Scholar

4. Wang, J. P., B.-Z. Wang, Y. X. Wang, and Y.-X. Guo, "Dual-band microstrip stepped-impedance bandpass filter with defected ground structure," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 4, 463-470, 2008.
doi:10.1163/156939308784150335 Google Scholar

5. Weng, M.-H., C.-H. Kao, and Y.-C. Chang, "A compact dual-band bandpass filter using cross-coupled asymmetric SIRs for WLANs," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 2-3, 161-168, 2010.
doi:10.1163/156939310790735679 Google Scholar

6. Weng, M.-H., S.-K. Liu, H.-W. Wu, and C.-H. Hung, "A dual-band bandpass filter having wide and narrow bands simultaneously using multilayered stepped impedance resonators ," Progress In Electromagnetics Research Letters, Vol. 13, 139-147, 2010.
doi:10.2528/PIERL10022401 Google Scholar

7. Fan, J.-W., C.-H. Liang, and X.-W. Dal, "Design of cross-coupled dual-band filter with equal length split-ring resonators," Progress In Electromagnetics Research, Vol. 75, 285-293, 2007.
doi:10.2528/PIER07060904 Google Scholar

8. Xue, W., C.-H. Liang, X.-W. Dai, and J.-W. Fan, "Design of miniature planar dual-band filter with 0 feed structures," Progress In Electromagnetics Research, Vol. 77, 493-499, 2007.
doi:10.2528/PIER07090502 Google Scholar

9. Wu, G.-L., W. Mu, X.-W. Dai, and Y.-C. Jiao, "Design of novel dual-band bandpass filter with microstrip meander loop resonator and CSRR DGS," Progress In Electromagnetics Research, Vol. 78, 17-24, 2008.
doi:10.2528/PIER07090301 Google Scholar

10. Velazquez-Ahumada, M. D. C., J. Martel-Villagr, F. Medina, and F. Mesa, "Application of stub loaded folded stepped impedance resonators to dual band filter design," Progress In Electromagnetic Research, Vol. 102, 107-107124, 2010.
doi:10.2528/PIER10011406 Google Scholar

11. Zhang, X. Y., J. X. Chen, and Q. Xue, "Dual-band bandpass filter using stub-loaded resonators," IEEE Microw. Wireless Compon. Lett., Vol. 17, No. 8, 583-585, 2007.
doi:10.1109/LMWC.2007.901768 Google Scholar

12. Zhang, X. Y. and Q. Xue, "Novel centrally loaded resonators and their applications to bandpass filter," IEEE Trans. Microw. Theory Tech., Vol. 56, No. 4, 913-921, 2008.
doi:10.1109/TMTT.2008.919648 Google Scholar

13. Zhou, M.-Q., X.-H. Tang, and F. Xiao, "Compact dual band bandpass filter using novel E-type resonators with controllable bandwidths," IEEE Microw. Wireless Compon. Lett., Vol. 18, No. 12, 779-781, 2008.
doi:10.1109/LMWC.2008.2007696 Google Scholar

14. Chen, F. C., Q. X. Chu, and Z. H. Tu, "Tri-band bandpass filter using stub loaded resonators," Electron. Lett., Vol. 44, No. 12, 747-749, 2008.
doi:10.1049/el:20081054 Google Scholar

15. Chu, Q. X., F. C. Chen, Z. H. Tu, H. Wang, "A novel crossed resonator and its applications to bandpass filters," IEEE Trans. Microw. Theory Tech., Vol. 57, No. 7, 1753-1759, 2009.
doi:10.1109/TMTT.2009.2022873 Google Scholar

16. Chen, F. C., Q. X. Chu, and Z. H. Tu, "Design of compact dual-band bandpass filter using short stub loaded resonator," Microw. Opt. Technol. Lett., Vol. 51, No. 4, 959-963, 2009.
doi:10.1002/mop.24209 Google Scholar

17. Mondal, P. and M. K. Mandal, "Design of dual-band bandpass filters using stub-loaded open-loop resonators," IEEE Trans. Microw. Theory Tech., Vol. 56, No. 1, 150-155, 2008.
doi:10.1109/TMTT.2007.912204 Google Scholar

18. Chen, F. C. and J. M. Qiu, "Dual-band bandpass filter with controllable characteristics using stub-loaded resonators," Progress In Electromagnetics Research Letters, Vol. 28, 45-51, 2012.
doi:10.2528/PIERL11100904 Google Scholar

19. Zhang, X. Y., C. H. Chan, Q. Xue, and B. J. Hu, "Dual-band bandpass filter with controllable bandwidths using two coupling paths," IEEE Microw. Wireless Compon. Lett., Vol. 20, No. 11, 616-618, 2010.
doi:10.1109/LMWC.2010.2066553 Google Scholar

20. Chen, F. C. and Q. X. Chu, "Novel multistub loaded resonator and its application to high-order dual-band filters," IEEE Trans. Microwave Theory Tech., Vol. 58, No. 6, 1551-1556, 2010.
doi:10.1109/TMTT.2010.2049161 Google Scholar

Dr. Fu-Chang Chen

Dr. Jie Ming Qiu