A compact wideband bandpass filter is proposed in this letter by means of short-circuited-stub loaded ring resonator and tapped feed lines. After the principle of an initial filter with wide operating bandwidth is described, a prototype filter with center frequency at 3.23 GHz and fractional bandwidth of 86.1% is designed and fabricated. Measured results well agree with the predicted ones, verifying the design principle.
2. Razalli, M. S., A. Ismali, and M. A. Mahdi, "Novel compact microstrip ultra-wideband filter utilizing short-circuited stubs with less vias," Progress In Electromagnetics Research, Vol. 88, 91-104, 2008.
doi:10.2528/PIER08102303
3. Deng, H.-W., Y.-J. Zhao, L. Zhang, X.-S. Zhang, and W. Zhao, "Compact wideband bandpass filter with quadruple-mode stub-loaded resonator ," Progress In Electromagnetics Research Letters, Vol. 17, 125-132, 2010.
doi:10.2528/PIERL10081108
4. Jiang, B., L. Zhu, and D. Chen, "A novel wideband bandpass filter using triple-mode slotline ring resonator," Progress In Electromagnetics Research Letters, Vol. 40, 163-170, 2013.
5. Wang, H., L. Zhu, and W. Menzel, "Ultra-wideband bandpass filter with hybrid microstrip/CPW structure," IEEE Microw. Wireless Compon. Lett., Vol. 15, No. 12, 844-846, 2005.
doi:10.1109/LMWC.2005.860016
6. Sun, S. and L. Zhu, "Wideband microstrip ring resonator bandpass filters under multiple resonances," IEEE Trans. Microw. Theory Tech., Vol. 55, No. 10, 2176-2182, Oct. 2007.
7. Liu, W., Z. Ma, C.-P. Chen, G. Zheng, and T. Anada, "A novel ultra wideband bandpass filter using microstrip double-ring resonators," Microw. Opt. Technol. Lett., Vol. 49, No. 2, 303-305, Feb. 2007.
doi:10.1002/mop.22117
8. Zhu, L., H. Bu, and K.Wu, "Aperture compensation technique for innovative design of ultra-broadband microstrip bandpass filter," IEEE MTT-S Int. Dig., Vol. 1, 315-318, 2000.
9. Zhu, L. and W. Menzel, "Broad-band microstrip-to-CPW transition via frequency-dependent electromagnetic coupling," IEEE Trans. Microw. Theory Tech., Vol. 52, No. 5, 1517-1522, May 2004.
doi:10.1109/TMTT.2004.827034
10. Sun, S., L. Zhu, and H.-H. Tan, "A compact wideband bandpass filter using transversal resonator and asymmetrical interdigital coupled lines," IEEE Microw. Wireless Compon. Lett., Vol. 18, No. 3, 173-175, 2008.
doi:10.1109/LMWC.2008.916780
11. Hsieh, L.-H. and K. Chang, "Compact, low inserstion-loss, sharp-rejection, and wide-band microstrip bandpass filters," Microw. Opt. Technol. Lett., Vol. 51, No. 4, 1241-1246, Apr. 2003.
Submit
