A Simple Transformation of Improved WLAN Band Pass to Low Pass Filter Using Defected Ground Structure (DGS), Defected Microstrip Structure (DMS) and Multilayer-Technique

A. Boutejdar, A. Omar, M. Al Sharkawy, A. Darwish


A novel transformation of band pass- to low pass filter is introduced in this paper. First a compact microstrip band pass filter designed, optimized and realized by combining a simple multilayer method with magnetically coupled microstrip U-shaped DGS resonators is proposed. The DGS- and DMS-techniques demonstrated the ability to suppress the undesired harmonic response. The proposed band pass filter is transformed to a new structure with low pass characteristics using a simple strip connection between the neighboring microstrip resonators. The designed compact filters have low insertion loss, sharp transition regions due to the presence of two-transmission zeros at both edges of the pass bands. The measured resonance frequency, bandwidth and insertion loss are 3.4 GHz, 40%, and 0.5 dB respectively. The compact transformed low pass filter offers a wide stop band with a rejection higher than 20 dB up to more than 10 GHz. The undesired harmonic has been successfully suppressed. The simulated and measured results show good agreement and validate the proposed approach. 

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Zhang, X. Y. and Q. Xue, "Novel centrally loaded resonators and their applications to bandpass filters,`` IEEE Trans. Microw. Theory Tech., vol. 56, no. 4, pp. 913–921, Apr. 2008.

Kuo, J. T. and W. Hsu, "Parallel coupled microstrip filters with suppression of harmonic response,`` IEEE MicrowaveWireless Comp. Lett., vol. 12, pp. 383–385, Oct. 2002.

Hong, J. S. and M. J. Lancaster, "Cross-coupled microstrip hairpin-resonator filters``, IEEE Trans. Microwave Theory Tech., vol. 46, no. 1, pp. 118-122, Jan. 1998.

Awida, M., A. Boutejdar, A. Safwat, H. El-Hennawy, A. Omar, " Multi-bandpass filters using multi-armed open loop resonators with direct feed,`` IEEE MTT-S International Microwave Symposium, Honolulu, Hawaii, June 03 - 08, 2007.

Hsieh, L. H. and K. Chang, "Compact low pass filter using stepped impedance hairpin resonator,`` Electron Lett., vol. 37, pp. 899–900, (2001).

Boutejdar, A. and A. Omar, "Compensating For DGS Filter Loss,`` Microwave & RF Journal [Design Features], Issue 2, pp. 68-76, February. 2012.

Boutejdar, A., S. Amari, and A. Omar, "A Novel Compact J-Admittance Inverter-Coupled Microstrip Bandpass Filter Using Arrowhead-Shape As Defected Ground Structure (DGS),`` Microwave and Optical Technology Letters , vol. 52, Issue 1, pp: 34- 38, January 2010.

Abdel-Rahman, A., A. K. Verma, A. Boutejdar, and A. S. Omar, "Control of band-stop response of Hi-Lo microstrip low-pass filter using slot in ground plane``, IEEE Trans. on Microwave Theory and Tech., vol. 52, pp. 1008 – 1013, Mar. 2004.

Yang, Y. Y., R. C. Qian., and T. Itoh, "A novel low loss slow-wave microstrip structure``, IEEE IEEE Microwave Guide Wave Lett., vol. 47, no. 8, pp. 372 – 374, 1998.

Garde, L., M. J. Yabar, and C. D. Rio, "Simple modeling of DGS to design 1D-PBG low pass filter,`` Microw. Opt Technol. Lett., vol. 37, no. 3, pp. 228–232, May 2003.

Ahn, D., J. S. Park, C. S. Kim, Y. Qian, and T. Itoh, "A design of the low-pass filter using the novel microstrip defected ground structure,`` IEEE Trans. Microwave Theory Tech., vol. 49, pp. 86–93, Jan. 2001.

Boutejdar, A. "An Improvement of Defected Ground Structure Lowpass/Bandpass Filters Using H-Slot Resonators and Coupling Matrix Method``, Journal of Microwaves, Optoelectronics and Electromagnetic Applications, vol. 10, Issue 2, pp. 295-307, ISSN 2179-1074, December 2011.

Kim, C. S., J. S. Lim, S. Nam, K. Y. Kang, and D. Ahn, "Equivalent circuit modeling of spiral defected ground structure for microstrip line,`` Electron. Lett., vol. 38, no. 19, pp. 1109–1120, 2002.

Al Sharkawy, M., A. Boutejdar, D. Abd El Aziz, and E. Galal, "Design Of Compact Microstrip Filter With Large Reject Band Using A New Multi-Sections T-Shaped Defected Ground Structure and Multilayer Technique``, Microwave and Optical Technology Letters, vol. 53, isuue 04, pp. 35-39, May 2011.

Kim, J. P. and W. S. Park, "Microstrip Low Pass Filter with Multislots on Ground Plane,`` Electronics Letters, vol. 37, no. 25, December 2001.

Park, J. S., H. S. Yun, and D. Ahn, "A design of the novel coupled line bandpass filter using defected ground structure with wide stopband performance,`` IEEE Trans. Microw. Theory Tech., vol. 50, no. 9, pp. 2037–2043, Sep. 2002.

Boutejdar, A., A. Elsherbini, and A. S. Omar, "Method for widening the reject-band in low-pass/band-pass filters by employing coupled C-shaped defected ground structure``, IET Microwaves Antennas & Propagation, vol. 2, Issue 8, pp. 759-765, Dec 2008.

Kim, C., J. S. Park, A. Dal, and J. Kim, "A novel 1-D periodic defected ground structure for planar circuits,`` IEEE Microwave Guided Wave Lett., vol. 10, pp. 131–133, Apr. 2000.

Boutejdar, A. et al., "Improvement of microstrip low pass filters' characteristics using an optimized number of new multi-ring defected ground structures``, Microwave and Optical Technology Letters, vol. 49 Issue 12, pp. 3074-3078, Dec. 2007.

Boutejdar, A., A. Batmanov, A. Elsherbini, A. S. Omar, and E. P. Burte, "A Miniature 3.1-GHz Microstrip Bandpass Filter with A Suppression of Spurious Harmonic Using Multilayer-Technique and Defected Ground Structure Open Loop-Ring (DGS)``, Proc. EUROEM European Electromagnetic 2008, Lausanne, Switzerland, 21-25 July 2008.

Boutejdar, A., A. Omar, E. P. Burte, R. Mikuta, and A. Batmanov, "DGS and Multilayer Methods Make LPF``, Microwave & RF Journal[Design Features], pp. 61-72, issue March/April. 2011.

Boutejdar, A., A. Omar, E. P. Burte and R. Mikuta, " Design of Compact Ultra-Wide Stopband Lowpass Filter Using a U-Slotted Ground Structure (SGS) and Multilayer-Technique``, Recent Patents on Electrical Engineering journal, Bentham Science Publishers, ISSN: 1874-4761, vol. 4, issue 2, pp: 139-144, May 2011.

Cameron, R. J. "General coupling matrix synthesis method for Chebyshev filtering functions,`` IEEE Transactions On Microwave Theory And Techniques, vol. 47, No. 4, April 1999.

Amari, S. "Synthesis of Cross-Coupled Resonator Filters Using an Analytical Gradiant-Based Optimization Technique``, IEEE Trans. Microwave Theory Tech., vol. 48, No. 9, pp. 1559-1564, Sep. 2000.

Boutejdar, A., A. Elsherbini, A. Balalem, J. Machac, and A. Omar, "Design of new DGS hairpain microstrip bandpass filter using coupling matrix method,`` PIERS Progress in Electromagnetics Research Symposium, Prague, Czech Republic, pp. 261-265, August 27 - 30, 2007.

Abdel-Rahman, A., A. K. Verma, A. Boutejdar, and A. S. Omar, "Compact stub type microstrip bandpass filter using defected ground plane``, IEEE Microwave and Wireless Components Letters, vol. 14, pp.136-138, 2004.

Boutejdar, A., A. Elsherbini, and A. Omar, "Improvement of bassband and sharpness factor of parallel coupled microstrip bandpass filters using discontinuities correction,`` Mediterranea Microwave Symposium, Budapest, pp. 121- 124, 2007.

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DOI: http://dx.doi.org/10.1590/S2179-10742013000100010


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