In this paper, a new method is introduced to design a simple-profile hybrid coupler in two arbitrary frequency bands. The structure is achieved by means of dual-band quarter-wavelength transformers as the arms of a traditional branch line coupler. A prototype of the coupler operating at 0.9 GHz and 2.45 GHz is designed and fabricated to validate the robustness of the method. Comparing simulated with measured results, a good agreement is observed. Moreover, the performance of the coupler in terms of impedance bandwidth and isolation level between the input ports is compared with existing works. Further, the suggested coupler has the simplest profile resulting from the most flexible design process.
2. Nasseri, H., M. Bemani, and A. Ghaffarlou, "A new method for arbitrary amplitude distribution generation in 4 × 8 butler matrix," IEEE Microw. Wirel. Components Lett., Vol. 30, No. 3, 249-252, 2020, doi: 10.1109/LMWC.2020.2966929.
doi:10.1109/LMWC.2020.2966929
3. Ren, H., H. Zhang, Y. Jin, Y. Gu, and B. Arigong, "A novel 2-D 3 × 3 Nolen Matrix for 2-D beamforming applications," IEEE Trans. Microw. Theory Tech., Vol. 67, No. 11, 4622-4631, 2019, doi: 10.1109/TMTT.2019.2917211.
doi:10.1109/TMTT.2019.2917211
4. Qing, X. M., "Broadband aperture-coupled circularly polarized microstrip antenna fed by a three-stub hybrid coupler," Microw. Opt. Technol. Lett., Vol. 40, No. 1, 38-41, 2004, doi: 10.1002/mop.11280.
doi:10.1002/mop.11280
5. Phani Kumar, K. V. and S. S. Karthikeyan, "Miniaturised quadrature hybrid coupler using modified T-shaped transmission line for wide-range harmonic suppression," IET Microwaves, Antennas Propag., Vol. 10, No. 14, 1522-1527, 2016, doi: 10.1049/iet-map.2016.0301.
doi:10.1049/iet-map.2016.0301
6. Yoon, H. J. and B. W. Min, "Two section wideband 90˚ hybrid coupler using parallel-coupled three-line," IEEE Microw. Wirel. Components Lett., Vol. 27, No. 6, 548-550, 2017, doi: 10.1109/LMWC.2017.2701304.
doi:10.1109/LMWC.2017.2701304
7. Cheng, K. K. M. and F. L. Wong, "A novel approach to the design and implementation of dual-band compact planar 90˚ branch-line coupler," IEEE Trans. Microw. Theory Tech., Vol. 52, No. 11, 2458-2463, 2004, doi: 10.1109/TMTT.2004.837151.
doi:10.1109/TMTT.2004.837151
8. Zhang, H. and K. J. Chen, "A stub tapped branch-line coupler for dual-band operations," IEEE Microw. Wirel. Components Lett., Vol. 17, No. 2, 106-108, 2007, doi: 10.1109/LMWC.2006.890330.
doi:10.1109/LMWC.2006.890330
9. Gai, C., Y. C. Jiao, and Y. L. Zhao, "Compact dual-band branch-line coupler with dual transmission lines," IEEE Microw. Wirel. Components Lett., Vol. 26, No. 5, 325-327, 2016, doi: 10.1109/LMWC.2016.2549099.
doi:10.1109/LMWC.2016.2549099
10. Yeung, L. K., "A compact dual-band 90˚ coupler with coupled-line sections," IEEE Trans. Microw. Theory Tech., Vol. 59, No. 9, 2227-2232, 2011, doi: 10.1109/TMTT.2011.2160199.
doi:10.1109/TMTT.2011.2160199
11. Zhao, X., F. Zhu, K. Fan, G. Q. Luo, and K. Wu, "A compact dual-band coupler with coupled microstrip-slotlines," IEEE Microw. Wirel. Components Lett., 1-4, 2021, doi: 10.1109/lmwc.2021.3126698.
12. Jia, L., L. Zhang, and C. Zhang, "A dual-band and wide-band branch-line coupler with a large frequency ratio," Microw. Opt. Technol. Lett., Vol. 63, No. 1, 146-151, 2021, doi: 10.1002/mop.32592.
doi:10.1002/mop.32592
13. Zheng, S. Y., S. H. Yeung, W. S. Chan, K. F. Man, S. H. Leung, and Q. Xue, "Dual-band rectangular patch hybrid coupler," IEEE Trans. Microw. Theory Tech., Vol. 56, No. 7, 1721-1728, 2008, doi: 10.1109/TMTT.2008.925234.
doi:10.1109/TMTT.2008.925234
14. Bekasiewicz, A. and S. Koziel, "Miniaturised dual-band branch-line coupler," Electron. Lett., Vol. 51, No. 10, 769-771, 2015, doi: 10.1049/el.2015.0751.
doi:10.1049/el.2015.0751
15. Bckasiewicz, A. and S. Koziel, "Compact dual-band branch-line coupler with enhanced bandwidth for WLAN applications," 2019 Int. Appl. Comput. Electromagn. Soc. Symp. Miami, ACES-Miami 2019, 8-9, 2019.
16. Pozar, D. M., Microwave and Rf Design of Wireless Systems, Wiley, 2000.
17. Monzon, C., "A small dual-frequency transformer in two sections," IEEE Trans. Microw. Theory Tech., Vol. 51, No. 4, 1157-1161, 2003, doi: 10.1109/TMTT.2003.809675.
doi:10.1109/TMTT.2003.809675
18. Islam, R., A. I. Omi, M. A. Maktoomi, C. Zakzewski, and P. Sekhar, "A new coupled-line based dual-band branch-line coupler with port-extensions," Progress In Electromagnetics Research M, Vol. 105, 21-30, 2021.
doi:10.2528/PIERM21081203
19. Liu, Q., Y. Liu, Y. Wu, S. Li, C. Yu, and M. Su, "Broadband substrate integrated coaxial line to CBCPW transition for rat-race couplers and dual-band couplers design," Progress In Electromagnetics Research C, Vol. 35, 147-159, 2012.
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