PIER Letters
Progress In Electromagnetics Research Letters
ISSN: 1937-6480
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By W. Li, X. Cao, H. Lin, and Z.-X. Tang

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In this letter, an interdigital band-pass filter is proposed for out-of-band rejection improvement. Seven quarter-wavelength resonators are employed to form the passband. Three extra transmission zeros (TZs) on both sides of the passband are implemented by introducing source-load coupling and dumbbell defected ground structures (DGS). As demonstrated by the measured results, out-of-band rejection and selectivity are improved by these three TZs, and good performances are achieved. The proposed method of increasing out-of-band rejection is feasible and applicable in the design of modern microstrip filters.

W. Li, X. Cao, H. Lin, and Z.-X. Tang, "Design of an Interdigital Band-Pass Filter for Out-of-Band Rejection Improvement," Progress In Electromagnetics Research Letters, Vol. 64, 105-110, 2016.

1. Lai, Z., et al., "Compact multi-band transversal bandpass filters with source-load coupling," Journal of Electromagnetic Waves and Applications, Vol. 28, No. 2, 184-193, 2014.

2. Jankovic, N., et al., "A compact dual-band bandpass filter using folded quarter-wavelength resonators," 2012 42nd European Microwave Conference (EuMC), IEEE, 360-363, 2012.

3. Jankovic, N., V. Radonic, and V. Crnojevic-Bengin, "Compact tri-band bandpass filter based on quarter-wavelength resonators," Journal of Electromagnetic Waves and Applications, Vol. 27, No. 6, 750-757, 2013.

4. Yang, Z., et al., "Design of a compact dual-band dual-mode microstrip filter with an adjustable transmission zero," 2012 IEEE MTT-S International Microwave Symposium Digest (MTT), IEEE, 1-3, 2012.

5. Wang, L., et al., "Dual-band bandpass filter using stub loaded resonators with multiple transmission zeros," 2010 9th International Symposium on Antennas Propagation and EM Theory (ISAPE), IEEE, 1208-1211, 2010.

6. Cameron, R. J., "Advanced coupling matrix synthesis techniques for microwave filters," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 1, 1-10, 2003.

7. Zhou, M., X. Tang, and F. Xiao, "Compact dual band bandpass filter using novel E-type resonators with controllable bandwidths," Microwave and Wireless Components Letters, IEEE, Vol. 18, No. 12, 779-781, 2008.

8. Sun, S., L. Zhu, and H. H. Tan, "A compact wideband bandpass filter using transversal resonator and asymmetrical interdigital coupled lines," Microwave and Wireless Components Letters, IEEE, Vol. 18, No. 3, 173-175, 2008.

9. Pozar, D. M., Microwave Engineering, 4th Ed., John Wiley & Sons Inc., USA, 2012.

10. Cameron, R. J., C. M. Kudsia, and R. R. Mansour, Microwave Filters for Communication Systems: Fundamentals, Design, and Applications, John Wiley & Sons Inc., USA, 2007.

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

12. Montejo-Garai, J. R., "Synthesis of N-even order symmetric filters with N transmission zeros by means of source-load cross coupling," Electronics Letters, Vol. 36, No. 3, 232-233, 2000.

13. Amari, S., "Direct synthesis of folded symmetric resonator filters with source-load coupling," IEEE Microwave & Wireless Components Letters, Vol. 11, No. 6, 264-266, 2001.

14. Boutejdar, A., et al., "A simple transformation of improved WLAN band pass to low pass filter using defected ground structure (DGS), defected microstrip structure (DMS) and multilayer-technique," Journal of Microwaves, Optoelectronics and Electromagnetic Applications, Vol. 12, No. 1, 111-130, 2013.

15. Khan, M. T., et al., "Tuning of end-coupled line bandpass filter for 2.4GHz using defected ground structure (DGS) parameters," Business Engineering and Industrial Applications Colloquium (BEIAC), 2013 IEEE, 131-134, 2013.

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