volume | PIER Journals

Abstract

This paper presents a compact shorted stub-loaded quad-band bandpass filter. The proposed filter simultaneously operates at GSM (0.83-0.97 GHz), LTE2300 (2300-2400 MHz), WiMAX (3.3-3.7 GHz), and WLAN (5.725-5.825 GHz) bands. The filter has been designed using the technique of stub-loaded resonator (SLR). By changing the length of the center-loaded stub, the resonant frequency of the even-mode can be varied without affecting that of the odd-mode. This simplifies the design and tuning of the quad-band filter. Eight transmission zeros (TZs) around the three passband make the pass bands highly isolated. In order to validate its practicability, a quad-band bandpass filter (BPF) has been designed, fabricated and measured. Good agreement between simulated and measured results is observed.

1. Zhang, X. Y., J.-X. Chen, and Q. Xue, "Dual-band bandpass filters using stub-loaded resonators," IEEE Microwave and Wireless Components Letters, Vol. 17, No. 8, 583-585, August 2007.
doi:10.1109/LMWC.2007.901768

2. Lai, X., C.-H. Liang, H. Di, and B. Wu, "Design of tri-band filter based on stub loaded resonator and DGS resonator," IEEE Microwave and Wireless Compon Letters, Vol. 20, No. 5, 265-267, May 2010.
doi:10.1109/LMWC.2010.2045584

3. Lan, S. W., M. H. Weng, and S. J. Chang, "A tri-band bandpass filter with wide stopband using asymmetric stub-loaded resonators," IEEE Microwave and Wireless Components Letters, Vol. 25, No. 1, 19-21, January 2015.
doi:10.1109/LMWC.2014.2365739

4. Wei, F., Y. J. Guo, P.-Y. Qin, and X.W. Shi, "Compact balanced dual- and tri-band bandpass filtersbased on stub loaded resonators ," IEEE Microwave and Wireless Components Letters, Vol. 25, No. 2, 76-78, February 2015.
doi:10.1109/LMWC.2014.2370233

5. Murmu, L. and S. Das, "A dual-band bandpass filter for 2.4GHz bluetooth and 5.2GHz WLAN applications," Progress In Electromagnetics Research Letters, Vol. 53, 65-70, 2015.
doi:10.2528/PIERL15041601

6. Quendo, C., A. Manchec, Y. Clavet, E. Rius, J.-F. Favennec, and C. Person, "General synthesis of N-band resonator based on norder dual behavior resonator," IEEE Microwave and Wireless Components Letters, Vol. 17, No. 5, 337-339, May 2007.
doi:10.1109/LMWC.2007.895697

7. Zhang, Y., K. A. Zaki, J. A. Ruiz-Cruz, and A. E. Atia, "Analytical synthesis of generalized multi-band microwave filters," IEEE MTT-S Int. Microwave Symp. Dig., 1273-1276, June 2007.

8. Hejazi, Z. M., "A fast design approach of compact microstrip multiband bandpass filters," Microwave and Optical Technology Letters, Vol. 54, No. 4, 1075-1079, April 2012.
doi:10.1002/mop.26742

9. Wu, J. Y. and W. H. Tu, "Design of quad-band bandpass filter with multiple transmission zeros," Electronics Letters, Vol. 47, No. 8, 502-503, April 2011.
doi:10.1049/el.2011.0052

10. Cheng, C.-M. and C.-F. Yang, "Develop quad-band (1.57/2.45/3.5/5.2 GHz) bandpass filters on the ceramic substrate," IEEE Microwave and Wireless Components Letters, Vol. 20, No. 5, 268-270, May 2010.
doi:10.1109/LMWC.2010.2045585

11. Cho, Y. H. and S. W. Yun, "A tri-band bandpass filter using stub-loaded SIRs with controllable bandwidths," Microwave and Optical Technology Letters, Vol. 56, No. 12, 2907-2910, December 2014.
doi:10.1002/mop.28734

12. Mo, Y., K. Song, and Y. Fan, "Miniaturized triple-band bandpass filter using coupled lines and grounded stepped impedance resonators," IEEE Microwave and Wireless Components Letters, Vol. 24, No. 5, 333-335, May 2014.
doi:10.1109/LMWC.2014.2310458

13. Ching-Her, L., C. I. G. Hsu, and H. Chih-Chan, "Balanced dual-band BPF with stub-loaded SIRs for common-mode suppression," IEEE Microwave and Wireless Components Letters, Vol. 20, No. 2, 70-72, February 2010.
doi:10.1109/LMWC.2009.2038433

14. Jin, S. and X. Quan, "Novel balanced dual-band bandpass filter using coupled stepped-impedance resonators," IEEE Microwave and Wireless Components Letters, Vol. 20, No. 1, 19-21, January 2010.
doi:10.1109/LMWC.2009.2035954

15. Wei, W. H. and Y. R. Yuan, "A new quadband bandpass filter using asymmetric stepped impedance resonators," IEEE Microwave and Wireless Components Letters, Vol. 21, No. 4, 203-205, April 2011.
doi:10.1109/LMWC.2011.2106153

16. Wei, F., Q. L. Huang, W.-T. Li, and X.-W. Shi, "A compact quadband bandpass filter using novel stub loaded SIR structure," Microwave and Optical Technology Letters, Vol. 56, No. 3, 538-542, March 2014.
doi:10.1002/mop.28160

17. Xu, J., W. Wu, and C. Miao, "Compact microstrip dual-/tri-/quad-band bandpass filter using open stubs loaded shorted stepped-impedance resonator," IEEE Transactions on Microwave Theory and Techniques, Vol. 61, No. 9, 3187-3199, September 2013.
doi:10.1109/TMTT.2013.2273759

Dr. Lakhindar Murmu

Dr. Sushrut Das