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Compact Microstrip Bandpass Filter Improved by DMS and Ring Resonator

By Mahdi Oliaei, Majid Tayarani, and Mahmood Karami
Progress In Electromagnetics Research Letters, Vol. 45, 7-12, 2014


In this paper, complementary split ring resonators (CSRRs) as band-stop elements are used in combination with coupled microstrip lines as high and low pass elements to design and fabricate very compact bandpass filter (BPF) having controllable characteristics. The proposed filter provides several advantages such as compactness (occupying area less than 0.1λg × λg in which λg is calculated at center frequency of pass band), sharp rejection, low insertion loss (IL less than -8.5 dB in all of the bandwidth), good return loss (RL 3-dB bandwidth of roughly 2 GHz from 0.7 GHz to 2.7 GHz i.e. more than 115% FBW) and low cost. Defected Microstrip and Ring Resonator Structures have been used for eliminating the created spurious pass band in upper frequencies. The simulation results have been done with full-wave softwares i.e. CST and HFSS by time and frequency domain solvers, respectively. Also, the equivalent lossless lumped circuit of total structure has been obtained and simulated by ADS software. These simulated results show good agreements with experimental ones.


Mahdi Oliaei, Majid Tayarani, and Mahmood Karami, "Compact Microstrip Bandpass Filter Improved by DMS and Ring Resonator," Progress In Electromagnetics Research Letters, Vol. 45, 7-12, 2014.


    1. Veselago, V. G., "The electrodynamics of substances with simultaneously negative values of ε and μ," Sov. Phys. Usp., Vol. 10, 509-514, 1968.

    2. Almalkawi, M. J. and V. K. Devabhaktuni, "Compact realization of combline bandpass filter integrated with defected microstrip structure bandstop filter," Progress In Electromagnetics Research Letters, Vol. 35, 99-105, 2012.

    3. Lee, J. and Y. Kim, "Ultra-wideband bandpass filter with improved upper stopband performance using defected ground structure," IEEE Microw. Wireless Compon. Lett., Vol. 20, No. 6, 316-318, Jun. 2010.

    4. Hsieh, L. H. and K. Chang, "Compact, low insertion-loss, sharp-rejection, and wide-band microstrip bandpass filters," IEEE Trans. Microw. Theory Tech., Vol. 12, No. 4, 1241-1246, 2003.

    5. Zhu, L., H. Bu, and K. Wu, "Broadband and compact multi-pole microstrip bandpass filters using ground plane aperture technique," Proc. Inst. Elect. Eng., Vol. l49, No. 1, 71-77, 2002.

    6. Mondal, P., M. K. Mandal, and A. Chaktabarty, "Compact bandpass filters with wide controllable fractional bandwidth," IEEE Microwave and Wireless Components Letters, Vol. 16, No. 10, 71-77, 2006.

    7. Fallahzadeh, S. and M. Tayarani, "A compact microstrip bandstop filter," Progress In Electromagnetics Research Letters, Vol. 11, 167-172, 2009.

    8. Fallahzadeh, S., H. Bahrami, A. Akbarzadeh, and M. Tayarani, "High-isolation dual-frequency operation patch antenna using spiral defected microstrip structure," IEEE Antennas and Wireless Propagation Letters, Vol. 9, 122-124, 2010.

    9. Mallahzadeh, A. R., B. Rahmati, M. Alamolhoda, R. Sharifzadeh, and A. H. Ghasemi, "Ultra wide stop band LPF with using defected microstrip structures," IEEE Conference Publications, 6th European Conference on Antennas and Propagation (EUCAP), 1-3, 2012.

    10. Liu, H. W., Z. C. Zhang, S. Wang, L. Zhu, X. H. Guan, J. S. Lim, and D. Ahn, "Compact dual-band bandpass filter using defected microstrip structure for GPS and WLAN applications," IET Journals & Magazines, Electronics Letters, Vol. 46, 1444-1445, 2010.

    11. Marques, R., F. Martin, and M. Sorolla, Metamaterials with Negative Parameters, Theory, Design, and Microwave Application, John Wiley & Sons, Inc., 2008.

    12. Hong, J. S. and M. J. Lancaster, Microstrip Filters for RF/Microwave Applications, John Wiley & Sons, Inc., 2001.