volume | PIER Journals

Abstract

In this paper, novel compact low-pass filters using Hi-Lo technique and meander method are proposed. Series of the proposed filters are designed by adding modifications along the microstrip line (meander inductor) and by using U-form topology. The size of the proposed filter can be reduced by 15% compaired to the conventional filter while maintaining the optimal low-pass features. The compact meander LPF consists of two thin microstrip lines, which are connected with 50Ω microstrip feed lines and a microstrip patch placed in the middle of the structure. The thin lines and the microstrip patch correspond to inductance and capacitance, respectively. The proposed meander Hi-Lo topology has been mounted on an RO4003 substrate with a relative dielectric constant ε_r = 3.38, thickness h = 0.813 mm and loss tangent 0.0027. The compact L-band low-pass structure has a size of (0.263λ_g×0.175λ_g) where λ_g = 57 mm is the wavelength at the cutoff frequency 2.85 GHz. In addition to a good compactness, the structure exhibits a simple design, very low insertion loss in the passband (L-band) of less than 0.3 dB, and it achieves a wide rejection bandwidth with a 20 dB attenuation from 5.3 to 6.3 GHz. The excellent LPF characteristics are verified through simulations and measurements where a good consistency can be observed. Such compact filter structures are expected to be used in various microwave system applications.

1. Boutejdar, A., "Design of wide stop band L-band LPF based on DMS-DGS-technique for radar applications," International Journal of Microwave Science and Technology, 2015. Google Scholar

2. Parui, S. K. and S. Das, "Modeling of modified split-ring type defected ground structure and its application as bandstop filter," Radio Engineering Journal, Vol. 18, No. 2, 149-154, June 2009. Google Scholar

3. Boutejdar, A., A. El-Sherbini, and A. S. Omar, "Method for widening the reject-band in lowpass/bandpass filters by employing coupled C-shaped defected ground structure (DGS)," IET Microwaves, Antennas & Propagation, Vol. 17, No. 12, 1405-1408, December 2008. Google Scholar

4. Liu, H., Z. Li, X. Sun, and J. Mao, "A novel photonic band-gap microstrip structures for lowpass filters of wide stop-band," Microwave and Optical Technology Letters, Vol. 37, 470-472, 2003.
doi:10.1002/mop.10953 Google Scholar

5. Boutejdar, A., "Design of broad-stop band low pass filter using a novel quasi-Yagi-DGS-resonators and metal box-technique," Microwave and Optical Technology Letters, Vol. 56, No. 3, 523-528, 2014.
doi:10.1002/mop.28190 Google Scholar

6. Yang, J. and W. Wu, "Compact elliptical low-pass filter using defected ground structure," IEEE Wireless Comp. Lett., Vol. 18, No. 9, 2008. Google Scholar

7. Lim, J. S., C. S. Kim, D. Ahn, Y. C. Jeong, and S. Nam, "Design of low pass filter using defected ground," IEEE Trans. Microwave Theory and Techniques, Vol. 53, No. 8, 2539-2545, 2005.
doi:10.1109/TMTT.2005.852765 Google Scholar

8. Boutejdar, A., N. M. Eltabit, A. A. Ibrahim, and E. P. Burte, "Design of wide stop band L-band LPF based on DMS-DGS-technique for radar applications," International Journal of Microwave Science and Technology, Vol. 2015, Article ID 101602, 7 pages, Hindawi Publishing Corporation, 2015. Google Scholar

9. Tu, W. H. and K. Chang, "Compact microstrip low-pass filter with sharp rejection," IEEE Microwave and Wireless Components Letters, Vol. 15, No. 6, 404-406, June 2005.
doi:10.1109/LMWC.2005.850479 Google Scholar

10. Boutejdar, A., W. Abd Ellatif, A. A. Ibrahim, and M. Challal, "A simple transformation from lowpass to bandpass filter using a new quasi-arrow head defected ground structure resonator and gap-J-inverter," Microwave and Optical Technology Letters, Vol. 58, No. 4, 947-953, 2016.
doi:10.1002/mop.29705 Google Scholar

11. Boutejdar, A., "A new approach to design compact tunable BPF starting from simple LPF topology using a single T-DGS-resonator and ceramic capacitors," Microwave and Optical Technology Letters, Vol. 58, No. 5, 1142-1148, 2016.
doi:10.1002/mop.29757 Google Scholar

12. Ren, L.-Y., "Quad-band bandpass filter based on dual-plane microstrip/DGS slot structure," Electron. Lett., Vol. 46, 691-692, 2010.
doi:10.1049/el.2010.0618 Google Scholar

13. Hejazi, Z. M. and Z. Ali, "Multiband bandpass filters with suppressed harmonics using a novel defected ground structure," Microwave and Optical Technology Letters, Vol. 56, No. 11, 2726-2731, 2014.
doi:10.1002/mop.28682 Google Scholar

14. Boutejdar, A., A. Ramadan, M. Makkey, and A. S. Omar, "Design of compact microstrip lowpass filters using a U-shaped defected ground structure and compensated microstrip line," Proceedings of the 36th European Microwave Conference, 267-270, 2006. Google Scholar

15. Abdel-Rahman, A. B., A. K. Verma, A. Boutejdar, and A. S. Omar, "Control of bandstop response of Hi-Lo microstrip low-pass filter using slot in ground plane," IEEE Trans. Microwave Theory and Techniques, Vol. 52, No. 3, 1008-1013, 2004.
doi:10.1109/TMTT.2004.823587 Google Scholar

16. Boutejdar, A., M. Challal, A. Omar, E. Burte, R. Mikuta, and A. Azrar, "A novel band-stop filter using octagonal-shaped patterned ground structures along with interdigital and compensated capacitors," ACES Journal - The Applied Computational Electromagnetics, Vol. 26, No. 10, July 2011. Google Scholar

17. Murphy, L., M. Yazdani, and E. Arvas, "Ultra-wide stopband in a compact low pass filter using stepped impedance resonators and novel techniques," 2012 IEEE International Conference on Ultra-Wideband, 92-94, Syracuse, NY, 2012.
doi:10.1109/ICUWB.2012.6340430 Google Scholar

18. Mokhtaari, M., J. Bornemann, and S. Amari, "Coupling-matrix design of dual/triple-band uniplanar filters," IEEE MTT-S Int. Microw. Symp. Dig., 515-518, San Francisco, CA, June 2006. Google Scholar

19. Xiao, J.-K., W.-J. Zhu, and J.-S. Fu, "New bandstop filter using simple defected microstrip structure," Microwave Journal, Vol. 11, 2011. Google Scholar

20. Boutejdar, A. and W. A. E. Ali, "Improvement of compactness of low pass filter using new quasi-yagi-DGS-resonator and multilayer-technique," Progress In Electromagnetics Research C, Vol. 69, 115-124, 2016.
doi:10.2528/PIERC16073003 Google Scholar

21. Pozar, D. M., Microwave Engineering, 3rd Ed., John Wiley & Sons, Inc., 2005.

22. Hong, J. S. and M. J. Lancaster, Microstrip Filters for RF/Microwave Applications, J. Wiley & Sons, Inc., 2001.
doi:10.1002/0471221619

23. Yang, J., "Design of RF filter based on Richards transform and Kuroads rules," Journal of Taizhou University in China, Vol. 28, No. 3, 41-46, 2006. Google Scholar

24. AWR’s Microwave Office software, Inc., , http://web.awrcorp.com/.

25. Ansoft High Frequency Structure Simulator (HFSS), , Ver. 13, Ansoft Corporation, 2010.

Dr. Wael Abd Ellatif Ali

Dr. Ahmed Boutejdar