volume | PIER Journals

Abstract

In this paper, the applications of shunt open stubs are reported based on asymmetric half-wavelength resonators structure. To demonstrate the design ideas, the analysis methods of ABCD matrix and equivalent circuit are used. The multi-band bandpass, miniaturization and harmonic suppression by application of the shunt open stubs are demonstrated. The measured insertion loss of the dual-band filter with the center frequency of 1.9 and 5.8 GHz is less than 2.7 dB. The insertion loss of the tri-band filter with the center frequency of 1.5, 4 and 6.3 GHz is less than 2.7 dB. Furthermore, a compact bandpass filter with size around 12.3 mm*11.5 mm is designed and fabricated. The bandwidth of the filter is 120 MHz with the center frequency of 2.4 GHz and the insertion loss is less than -3 dB. Especially, the insertion loss is less than -20 dB from 2.8 GHz to 7 GHz. For the filters above, the simulated results and the measured results agree well.

1. Lee, S.-Y. and C.-M. Tsai, "New cross-coupled filter design using improved hairpin resonators," IEEE Trans. Microwave Theory Tech., Vol. 48, 2482-2490, Dec. 2000.
doi:10.1109/22.899002

2. Zhang, X. Y. and Q. Xue, "Novel centrally loaded resonators and their applications to bandpass filters," IEEE Trans. Microwave Theory Tech., Vol. 56, No. 4, Apr. 2008.

3. Hsieh, L.-H. and K. Chang, "Tunable microstrip bandpass filters with two transmission zeros," IEEE Trans. Microwave Theory Tech., Vol. 51, No. 2, Feb. 2003.

4. Myoung, S.-S. and J.-G. Yook, "Miniaturisation and harmonic suppression method of parallel coupled-line filters using lumped capacitors and grounding," Electron. Lett., Vol. 41, No. 15, 849-851, Jul. 2005.
doi:10.1049/el:20051727

5. Myoung, S.-S., Y. Lee, and J.-G. Yook, "Bandwidth-compensation method for miniaturized parallel coupled-line filters," IEEE Trans. Microw. Theory Tech., Vol. 55, No. 7, 1531-1538, Jul. 2007.
doi:10.1109/TMTT.2007.900310

6. Doan, M. T., W. Che, K. Deng, and W. Feng, "Compact tri-band bandpass filter using stub-loaded resonator and quarter-wavelength resonator," Microwave Conference Proceedings (CJMW), China-Japan Joint, 2011.

7. Wang, H., X. Li, and N. Zhang, "Applications of shunt open stubs in filter design," Electronics Letters, Vol. 47, No. 18, 1032-1033, 2011.
doi:10.1049/el.2011.2069

8. Tu, W.-H. and K. Chang, "Compact second harmonic-suppressed bandstopand bandpass filters using open stubs," IEEE Trans. Microwave Theory Tech., Vol. 54, No. 6, Jun. 2006.

9. Cheong, P., S.-W. Fok, and K.-W. Tam, "Miniaturized parallel coupled line bandpass filter with spurious-response suppression," IEEE Trans. Microw. Theory Tech., Vol. 53, No. 5, 1810-1816, May 2005.
doi:10.1109/TMTT.2005.847075

10. Wang, S.-M., C.-H. Chi, M.-Y. Hsieh, and C.-Y. Chang, "Miniaturized spurious passband suppression microstrip filter using meandered parallel coupled lines," IEEE Trans. Microw. Theory Tech., Vol. 53, No. 2, 747-753, Feb. 2005.
doi:10.1109/TMTT.2004.840619

11. W.-H., Tu, H. Li, K.A. Michalski, and K. Chang, "Microstrip open-loop ring bandpass filter using open stubs for harmonic suppression," IEEE MTT-S International Microwave Symposium Digest, 357-360, 2006.

12. Gupta, K. C., R. Garg, I. Bahl, and P. Bhartia, Microstrip Lines and Slotlines, 2nd Ed., Chapter 3, Artech House, 1996.

13. Yeh, Z.-Y. and Y.-C. Chiang, "A miniature CPW balun constructed with length-reduced 3 dB couples and a short redundant transmission line," Progress In Electromagnetics Research, Vol. 117, 195-208, 2011.

14. Xiong, J., H. Li, B.-Z. Wang, Y. Jin, and S. He, "Theoretical investigation of rectangular patch antenna miniaturization based on the dps-eng bi-layer super-slow TM wave," Progress In Electromagnetics Research, Vol. 118, 379-396, 2011.
doi:10.2528/PIER11052601

15. Saleem, R. and A. K. Brown, "Empirical miniaturization analysis of inverse parabolic step sequence based UWB antennas," Progress In Electromagnetics Research, Vol. 114, 369-381, 2011.

16. Pu, T.-L., K.-M. Huang, B. Wang, and Y. Yang, "Application of micro-genetic algorithm to the design of matched high gain patch antenna with zero-refractive-index metamaterial lens," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 8--9, 1207-1217, 2010.
doi:10.1163/156939310791586025

17. Zhou, H., S. Qu, Z. Pei, Y. Yang, J. Zhang, J. Wang, H. Ma, C. Gu, X.-H. Wang, and Z. Xu, "A high-directive patch antenna based on all-dielectric near-zero-index metamaterial superstrates," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 10, 1387-1396, 2010.
doi:10.1163/156939310791958680

18. Costanzo, S., "Synthesis of multi-step coplanar waveguide-to-microstrip transition," Progress In Electromagnetics Research, Vol. 113, 111-126, 2011.

19. Tahir, F. A. and H. Aubert, "Equivalent electrical circuit for designing mems-controlled reflect array phase shifters," Progress In Electromagnetics Research, Vol. 100, 1-12, 2010.
doi:10.2528/PIER09112506

20. Ho, M.-H. and P.-F. Chen, "Suspended substrate stripline bandpass filters with source-load coupling structure using lumped and full-wave mixed approach," Progress In Electromagnetics Research, Vol. 122, 519-535, 2012.
doi:10.2528/PIER11102502

21. Wu, S.-M., C.-T. Kuo, and C.-H. Chen, "Very compact full differential bandpass filter with transformer integrated using integrated passive device technology," Progress In Electromagnetics Research, Vol. 113, 251-267, 2011.

22. 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:10.2528/PIER10070403

Professor Xiuping Li

Dr. Huisheng Wang