A compact tunable dual-band bandpass filter (BPF) based on substrate integrated waveguide (SIW) and defected ground structure (DGS) is investigated in this paper. The second passband can be flexibly controlled by changing the dimensions of the up-down DGSs whereas the first passband is fixed. The proposed filter exhibits improved selectivity due to the introduction of four left-right DGSs generating transmission zeroes. To verify the design method, a compact dual-band filter with the second center frequency switched among 5.4 GHz, 5.8 GHz, 6.4 GHz and 6.8 GHz and the first center frequency fixed at 4.78 GHz, is designed and fabricated. The simulated and measured results are in good agreement with each other.
2. Li, D., C. Tong, J. Bao, P. Peng, and D. Yu, "A novel bandpass filter of substrate integrated waveguide (SIW) based on S-shaped EBG," Progress In Electromagnetics Research Letters, Vol. 36, 191-200, 2013.
3. Zhang, Q. L., W. Y. Yin, S. He, and L. S. Wu, "Evanescent-mode substrate integrated waveguide (SIW) filters implemented with complementary split ring resonators," Progress In Electromagnetcs Research, Vol. 111, 419-432, 2011.
4. Deslandes, D. and K. Wu, "Accurate modeling, wave mechanism, and design consideration of a substrate integrated waveguide," IEEE Trans. on Microw. Theory and Tech., Vol. 54, No. 6, 2516-2526, Jun. 2006.
5. Hao, Z. C., W. Hong, J. X. Chen, X. P. Chen, and K. Wu, "Compact super-wide bandpass substrate integrated waveguide (SIW) filters," IEEE Trans. on Microw. Theory and Tech., Vol. 53, No. 9, 2968-2977, Sep. 2005.
6. Zhang, Y. L., W. Hong, K. Wu, J. X. Chen, and H. J. Tang, "Novel substrate integrated waveguide cavity filter with defected ground structure," IEEE Trans. on Microw. Theory and Tech., Vol. 53, 1280-1286, 2005.
7. Leszczynska, N., L. Szydlowski, and M. Mrozowski, "A novel synthesis technique for microwave bandpass filters with frequency-dependent couplings," Progress In Electromagnetics Research, Vol. 137, 35-50, 2013.
8. Deng, Z., W. Jiang, S. Gong, Y. Xu, and Y. Zhang, "A new method for broadening bandwidths of circular polarized microstrip antennas by using DGS parasitic split-ring resonators," Progress In Electromagnetics Research, Vol. 136, 739-751, 2013.
9. Taher, H., "A simplified equivalent circuit model for defected ground structures in planar transmission lines," Progress In Electromagnetics Research Letters, Vol. 29, 157-166, 2012.
10. Liu, J., K. P. Esselle, S. G. Hay, and S. S. Zhong, "Study of an extremely wideband monopole antenna with triple band-notched characteristics," Progress In Electromagnetics Research, Vol. 123, 143-158, 2012.
11. Lim, P. L. and K. M. Lum, "A novel bandpass filter design using E-shaped resonator and dual square-loop defected ground structure," PIERS Proceedings, 610-614, Kuala Lumpur, Malaysia, Mar. 27-30, 2012.
12. Ghazali, A. N. and S. Pal, "Analysis of a small UWB filter with notch and improved stopband," Progress In Electromagnetics Research Letters, Vol. 34, 147-156, 2012.
13. Wei, S., W.-Y. Yin, and X.-W. Sun, "Compact substrate integrated waveguide (SIW) filter with defected ground structure," IEEE Microwave and Wireless Components Letters, Vol. 21, No. 2, 83-85, 2011.
14. Wang, Z.-D., F. Wei, L. Zhang, and X.-W. Shi, "Design of dual-band bandpass SIW filter with DGS," 2012 International Conference on Microwave and Millimeter Wave Technology, 1-3, Piscataway, NJ, USA, May 5-8, 2012.
15. Huang, Y., Z. Shao, and L. Liu, "A substrate integrated waveguide bandpass filter using novel defected ground structure shape," Progress In Electromagnetics Research, Vol. 135, 201-213, 2013.
16. Chu, H. and X. Q. Shi, "Compact ultra-wideband bandpass filter based on SIW and DGS technology with a notch band," Journal of Electromagnetic Waves and Applications, Vol. 25, No. 4, 589-596, 2011.
17. He, Z., J. Cai, Z. Shao, X. Li, and Y. Huang, "A novel power divider integrated with SIW and DGS technology," Progress In Electromagnetics Research, Vol. 139, 289-301, 2013.
18. Jedrzejewski, A., N. Leszczynska, L. Szydlowski, and M. Mrozowski, "Zero-pole approach to computer aided design of in-line SIW filters with transmission zeros," Progress In Electromagnetics Research, Vol. 131, 517-533, 2012.
19. Wang, J., H. Ning, Q. Xiong, M. Li, and L.-F. Mao, "A novel miniaturized dual-band bandstop filter using dual-plane defected structures," Progress In Electromagnetics Research, Vol. 134, 397-417, 2013.
20. Zhang, Q., B.-Z. Wang, W.-Y. Yin, and L.-S. Wu, "Design of a miniaturized dual-band double-folded substrate integrated waveguide bandpass filter with controllable band-widths," Progress In Electromagnetics Research, Vol. 136, 211-223, 2013.
21. Chen, L.-N., Y.-C. Jiao, Z. Zhang, F.-S. Zhang, and Y.-Y. Chen, "Miniaturized dual-mode substrate integrated waveguide (SIW) band-pass filters loaded by double/single T-shaped structures," Progress In Electromagnetics Research Letters, Vol. 29, 65-74, 2012.
22. Liu, C. and K. Huang, "A compact substrate integrated waveguide band-pass filter," PIERS Proceedings, 1135-1138, Cambridge, USA, Jul. 5-8, 2010.