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A compact and wideband rat-race coupler using two-section ring and artificial transmission lines

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Abstract

A compact and wideband microstrip rat-race coupler employing two-section ring and artificial transmission lines (ATLs) is reported in this paper. The bandwidth is highly improved by using a two-section rat-race coupler. The physical size of the planar circuit is reduced based on the substitution of the microstrip line with an ATL. The area of the proposed design footprint is 35% of the area of the conventional similar design. The proposed coupler operates over a frequency range of 0.9 GHz to 1.85 GHz. In the desired band, the maximum measured amplitude imbalance is 0.6 dB, the phase variation is ± 7°, and the measured return loss is greater than 15 dB with isolation better than 20 dB. The prototype has been fabricated and measured, and the results are compared with the simulated data to validate the theory.

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References

  1. Xu, H., Wang, G., & Lu, K. (2011). Microstrip rat-race couplers. IEEE Microwave Magazine, 12(4), 117–129.

    Article  Google Scholar 

  2. Mohra, A. S., Sheta, A. F., & Mahmoud, S. F. (2004). New compact 3 dB 0/180° microstrip coupler configurations. Applied Computational Electromagnetic Society Journal, 19(2), 108–112.

    Google Scholar 

  3. Eccleston, K. W., & Ong, S. H. M. (2003). Compact planar microstripline branch-line and rat-race couplers. IEEE Transactions on Microwave Theory and Techniques, 51(10), 2119–2125.

    Article  Google Scholar 

  4. Caillet, M., Clenet, M., Sharaiha, A., & Antar, Y. M. M. (2009). A compact wide-band rat-race hybrid using microstrip lines. IEEE Microwave and Wireless Components Letters, 19(4), 191–193.

    Article  Google Scholar 

  5. Wang, C., Ma, T., & Yang, C. (2007). A new planar artificial transmission line and its applications to a miniaturized butler matrix. IEEE Transactions on Microwave Theory and Techniques, 55(12), 2792–2801.

    Article  Google Scholar 

  6. Jung, S., Negra, R., & Ghannouchi, F. M. (2008). A design methodology for miniaturized 3-dB branch-line hybrid couplers using distributed capacitors printed in the inner area. IEEE Transactions on Microwave Theory and Techniques, 56(12), 2950–2953.

    Article  Google Scholar 

  7. Ghali, H., & Moselhy, T. A. (2004). Miniaturized fractal rat-race, branch-line, and coupled-line hybrids. IEEE Transactions on Microwave Theory and Techniques, 52(11), 2513–2520.

    Article  Google Scholar 

  8. Akhtar, N., Kashif, A. U., Hayat, K., Bhatti, N. S., & Imran, M. (2014). A compact wideband hybrid ring for S-band pulsed and CW applications. In Proceedings of 2014 11th international Bhurban conference on applied sciences & technology (IBCAST) Islamabad (pp. 471–473), Pakistan, 14th–18th January, 2014, Islamabad.

  9. Muraguchi, M., Yukitake, T., & Naito, Y. (1983). Optimum design of 3-Db branch-line couplers using microstrip lines. IEEE Transactions on Microwave Theory and Techniques, 31(8), 674–678.

    Article  Google Scholar 

  10. Gruszczynski, S., & Wincza, K. (2012). Broadband rat-race couplers with coupled-line section and impedance transformers. IEEE Microwave and Wireless Components Letters, 22(1), 22–24.

    Article  Google Scholar 

  11. Sahoo, A. K. & Rawat, K. (2018). A wideband rat-race coupler using stepped impedance resonator. In 2018 IEEE MTT-S International Wireless Symposium (IWS), Chengdu (pp. 1–3).

  12. Denis, A. L. (2017). Miniature microstrip rat-race couplers with artificial transmission lines. In 2017 40th international conference on telecommunications and signal processing (TSP), Barcelona (pp. 802–805).

  13. Ghaffarian, M. S., Moradi, G. & Mousavi, P. (2019). Dual band/dual mode branch-line/rat-race coupler using artificial transmission line. In 2019 27th Iranian conference on electrical engineering (ICEE), Yazd, Iran (pp. 1622–1626).

  14. Chang, L., & Ma, T. (2017). Dual-mode branch-line/rat-race coupler using composite right-/left-handed lines. IEEE Microwave and Wireless Components Letters, 27(5), 449–451.

    Article  Google Scholar 

  15. Eskandari, A. R., Moghaddasi, M. N. & Honarvar, M. A. (2009). Design of a novel circularly polarized microstrip patch antenna using EBG structure. In 2009 mediterrannean microwave symposium (MMS), Tangiers (pp. 1–4).

  16. Khandelwal, A., Gupta, S. & Shambavi, K. (2017). Design and analysis of rat race coupler at C band. In 2017 international conference on intelligent computing and control systems (ICICCS), Madurai (pp. 1126–1130).

  17. Gupta, H., Mehta, A. & Shambavi, K. (2016). Miniaturization of a novel rat race coupler: A comparative analysis. In 2016 thirteenth international conference on wireless and optical communications networks (WOCN), Hyderabad (pp. 1–3).

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Correspondence to Ahmadreza Eskandari.

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Khanmohamadi, S., Eskandari, A. A compact and wideband rat-race coupler using two-section ring and artificial transmission lines. Analog Integr Circ Sig Process 108, 1–6 (2021). https://doi.org/10.1007/s10470-020-01743-5

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  • DOI: https://doi.org/10.1007/s10470-020-01743-5

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