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Abstract

Two compact CPW-fed band-pass filters using dual-mode resonator are proposed and studied - one resonator with two unequal corner-cut elements located at two diagonal corners of a conventional micro-strip patch and the other with unequal crossed slots at the center of a conventional micro-strip patch. In this paper, adjusting the length of corner-cut element and the crossed slot are mainly studied. By use of HFSS, the simulation results are given and analyzed. The simulation results show that the pass-band of the filter(a) may be adjusted over the bandwidth range from 4.9% to 16%, and the pass-band of the filter(b) may be adjusted over the bandwidth range from 5.4% to 8.2%, and filter(b) with cross-slot has smaller size than filter(a) with corner-cut to meet the same application demand. According to the simulation results, to design a filter which works at 1.65 GHz, the configuration of filter(b) is adopted owning to smaller size. finally, filter(b) with len1=20.2mm and len2=20.4mm is fabricated and measured, which has a minimum insertion loss of 2.48 dB in its pass-band.

1. Wolff, I., "Microstrip bandpass filter using degenerate modes of a microstrip ring resonator," Electron. Lett., Vol. 8, No. 12, 302-303, June 1972.
doi:10.1049/el:19720223

2. Matsuo, M., H. Yabuki, and M. Makimoto, "Dual-mode stepped impedance ring resonator for bandpass filter applications," IEEE Trans. Microwave Theory Tech., Vol. 49, 1235-1240, July 2001.

3. Hong, J.-S. and S. Li, "Dual-mode microstrip triangular patch resonators and filters," IEEE MTT-S Int. Microwave Symp. Dig., 1901-1904, 2003.

4. Waegel, K. H. and R. Bauer, "Slot coupled dual-mode patch filters," Electron. Lett., Vol. 32, No. 10, 878-879, May 1996.
doi:10.1049/el:19960618

5. Zhao, L.-P., X. Zhai, B. Wu, et al. "Novel design of dualmode bandpass filter using rectangle structure," Progress In Electromagnetics Research B, Vol. 3, 131-141, 2008.
doi:10.2528/PIERB07121003

6. Wu, G.-L., W. Mu, X.-W. Dai, et al. "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

7. Wang, Y.-X., B.-Z. Wang, and J. P. Wang, "A compact square loop dual-mode bandpass filter with wide stop-band ," Progress In Electromagnetics Research, Vol. 77, 67-73, 2007.
doi:10.2528/PIER07072707

8. Zhu, L., P.-M. Wecowski, and K. Wu, "New planar dual-mode filter using cross-slotted patch resonator for simultaneous size and loss reduction ," IEEE Trans. Microwave Theory Tech., Vol. 47, 650-654, May 1999.
doi:10.1109/22.763171

9. Chen, Z.-X., X.-W. Dai, and C.-H. Liang, "Novel dual-mode dualband bandpass filter using double square-loop structure," Progress In Electromagnetics Research, Vol. 77, 409-416, 2007.
doi:10.2528/PIER07082803

10. Zhao, L.-P., X.-W. Dai, Z.-X. Chen, et al. "Novel design of dual-mode dual-band bandpass filter with triangular resonators," Progress In Electromagnetics Research, Vol. 77, 417-424, 2007.
doi:10.2528/PIER07090501

11. Huang, X. D. and C. H. Cheng, "A novel coplanar-waveguide bandpass filter using a dual-mode square-ring resonator," IEEE Trans. Microw. Wireless Compon. Lett., Vol. 16, No. 1, 13-15, Jan. 2006.
doi:10.1109/LMWC.2005.861358

12. Zhang, X. Y. and Q. Xue, "Novel dual-mode dual-band filters using coplanar-waveguide-fed ring resonators," IEEE Trans. Microwave Theory Tech., Vol. 55, 2183-2190, October 2007.
doi:10.1109/TMTT.2007.906501

13. Garg, R., P. Bhartai, I. Bahl, et al. Microstrip Antenna Design Handbook, 493-500, Artech House, 2000, www.artechhouse.com.

14. Hu, H. L. and C. H. Cheng, "A cpw bandpass filter using a dualmode square patch resonator," Journal of Microwaves, Vol. 23, No. 2, 59-62, April 2007(in Chinese).

Dr. Jian Wang

Dr. Hou Zhang

Dr. Lai-Xuan Ma

Dr. Hai-Yang Xu