Progress In Electromagnetics Research M
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By C. Wang and W. Tang

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In this paper, a planar simplified dual composite right/left-handed (SD-CRLH) transmission line (TL) structure is proposed and applied to the design of branch-line coupler. The SD-CRLH TL is obtained by a microstrip line with an open-ended stub in spiral form. Since this structure has unusual phase shift characteristics with a transmission zero out of the passband, the branch-line coupler with the planar SD-CRLH TL can achieve both size reduction and harmonic suppression. Such a branch-line coupler operating at 0.915 GHz is investigated and fabricated. The equivalent circuit simulation, full-wave simulation and measurement results agree well with each other. From the results, it is shown that the area of the proposed branch line coupler is reduced by 74% compared to the conventional one while maintaining similar performance, and the second harmonic suppression can be lower than -45 dB.

C. Wang and W. Tang, "Compact Branch-Line Coupler with Harmonic Suppression Based on a Planar Simplified Dual Composite Right/Left-Handed Transmission Line Structure," Progress In Electromagnetics Research M, Vol. 69, 127-138, 2018.

1. Pozar, D. M., Microwave Engineering, John Wiley & Sons, New York, 2005.

2. Vogel, R. W., "Analysis and design of lumped-and lumped-distributed-element directional couplers for MIC and MMIC applications," IEEE Trans. Microw. Theory Tech., Vol. 40, No. 2, 253-262, Feb. 1992.

3. Tang, C. W. and M. G. Chen, "Synthesizing microstrip branch-line couplers with predetermined compact size and bandwidth," IEEE Trans. Microw. Theory Tech., Vol. 55, No. 9, 1926-1934, Sep. 2007.

4. Jung, S. C., R. Negra, and F. M. Ghannouchi, "A design methodology for miniaturized 3-dB branch-Line hybrid couplers using distributed capacitors printed in the inner area," IEEE Trans. Microw. Theory Tech., Vol. 56, No. 12, 2950-2953, Dec. 2008.

5. Tseng, C. H. and C. L. Chang, "A rigorous design methodology for compact planar branch-line and rat-race couplers with asymmetrical T-structures," IEEE Trans. Microw. Theory Tech., Vol. 60, No. 7, 2085-2092, Jul. 2012.

6. Krishna, I. S., R. K. Barik, S. S. Karthikeyan, and P. Kokil, "A miniaturized harmonic suppressed 3 dB branch line coupler using H-shaped microstrip line," Microw. and Opt. Technol. Lett., Vol. 59, No. 4, 913-918, 2017.

7. Tsai, K.-Y., H.-S. Yang, J.-H. Chen, and Y.-J. E. Chen, "A miniaturized 3 dB branch-line hybrid coupler with harmonics suppression," IEEE Microw. Wirel. Compon. Lett., Vol. 21, 537-539, 2011.

8. Dwari, S. and S. Sanyal, "Size reduction and harmonic suppression of microstrip branch-line coupler using defected ground structure," Microw. and Opt. Technol. Lett., Vol. 48, No. 10, 1966-1969, 2006.

9. Savitri, B., V. A. Fono, B. Alavikia, L. Talbi, and K. Hettak, "Novel approach in design of miniaturized passive microwave circuit components using metamaterials," Microw. and Opt. Technol. Lett., Vol. 59, No. 6, 1341-1347, 2017.

10. Ghali, H. and T. A. Moselhy, "Miniaturized fractal rat-race, branch-line, and coupled-line hybrids," IEEE Trans. Microw. Theory Tech., Vol. 52, No. 11, 2513-2520, Nov. 2004.

11. Velan, S. and M. Kanagasabai, "Compact microstrip branch-line coupler mwith wideband quadrature phase balance," Microw. and Opt. Technol. Lett., Vol. 58, No. 6, 1369-1374, 2016.

12. Reshma, S. and M. K. Mandal, "Miniaturization of a 90◦ hybrid coupler with improved bandwidth performance," IEEE Microw. Wirel. Compon. Lett., Vol. 26, 891-893, 2016.

13. Lai, A., T. Itoh, and C. Caloz, "Composite right/left-handed transmission line metamaterials," IEEE Microw. Mag., Vol. 5, No. 3, 34-50, 2004.

14. Yang, T., P. L. Chi, and T. Itoh, "Compact quarter-wave resonator and its applications to miniaturized diplexer and triplexer," IEEE Trans. Microw. Theory Tech., Vol. 59, No. 2, 260-269, Feb. 2011.

15. Xu, H. X., et al., "Dual-shunt branch circuit and harmonic suppressed device application," Appl. Phys. A, Vol. 108, No. 2, 497-502, 2012.

16. Xu, H. X., G. M. Wang, X. Chen, and T. P. Li, "Broadband balun using fully artificial fractalshaped composite right/left handed transmission line," IEEE Microw. Wirel. Compon. Lett., Vol. 22, No. 1, 16-18, 2012.

17. Caloz, C., T. Itoh, and A. Rennings, "CRLH metamaterial leaky-wave and resonant antennas," IEEE Antennas Propag. Mag., Vol. 50, No. 5, 25-39, 2008.

18. Xu, H. X., et al., "Analysis and design of two-dimensional resonant-type composite right left handed transmission lines with compact gain-enhanced resonant antennas," IEEE Trans. Antennas Propag., Vol. 61, No. 2, 735-747, 2013.

19. Xu, H. X., G. M.Wang, M. Q. Qi, and T. Cai, "Compact fractal left-handed structures for improved cross-polarization radiation pattern," IEEE Trans. Antennas Propag., Vol. 62, No. 2, 546-554, 2014.

20. Iyer, A. K. and G. V. Eleftheriades, "Free-space imaging beyond the diffraction limit using a Veselago-Pendry transmission-line metamaterial superlens," IEEE Trans. Antennas Propag., Vol. 57, No. 6, 1720-1727, 2009.

21. Xu, H. X., et al., "Metamaterial lens made of fully printed resonant-type negative-refractive index transmission lines," Appl. Phys. Lett., Vol. 102, 193502, 2013.

22. Caloz, C., "Dual Composite Right/Left-Handed (D-CRLH) transmission line metamaterial," IEEE Microw. Wirel. Compon. Lett., Vol. 16, 585-587, 2006.

23. Wang, C., et al., "Ultra-wideband bandpass filter using simplified dual composite right/left-handed transmission line structure," Microw. and Opt. Technol. Lett., Vol. 55, No. 5, 1165-1167, 2013.

24. Tang, W., X. He, T. Pan, and Y. L. Chow, "Synthetic asymptote formulas of equivalent circuit components of square spiral inductors," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 2, 215-226, 2006.

25. Chow, Y. L. and W. C. Tang, "Development of CAD formulas of integrated circuit componentsfuzzy EM formulation followed by rigorous derivation," Journal of Electromagnetic Waves and Applications, Vol. 15, No. 8, 1097-1119, 2001.

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