Stepped Impedance Microstrip Directional Coupler With High Directivity Performance
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Abstract
A directional microstrip coupler utilizing the stepped impedance coupled lines to equalize the even- and odd-mode phase velocities for directivity enhancement is investigated. The stepped impedance coupler features simple analysis, design, and implementation, with small area requirement, no use of lumped reactive components, and no via holes. Experimental results demonstrate a performance improvement in terms of the directivity by as large as 48.6 dB over the conventional coupler.
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Copyright @2021 Engineering Transactions
Faculty of Engineering and Technology
Mahanakorn University of Technology
References
A. Podell, “A high directivity microstrip coupler technique,” in IEEE MTT-S Int. Microw. Symp. Dig., May 1970, pp. 33–36.
S.-F. Chang, J.-L. Chen, Y.-H. Jeng, and C.-T. Wu, “New high-directivity coupler design with coupled spurlines,” IEEE Microw. Wireless Compon. Lett., vol. 14, no. 2, pp. 65–67, Feb. 2004.
L. Su, T. Itoh, and J. Rivera, “Design of an overlay directional coupler by a full-wave analysis,” in IEEE MTT-S Int. Microw. Symp. Dig., May 1983, pp. 427–429.
C.-S. Kim, S.-W. Lee, P.-Y. Lee, H.-S. Kim, J.-S. Park, and D. Ahn, “Design of re-entrant mode microstrip directional coupler for high directivity performance,” Asia-Pacific, Microwave Conf., 2000. pp. 1286-1289.
J. Shi, X.Y. Zhang, K.W. Lau, J.-X., Chen, and Q, Xue, “Directional coupler with high directivity using metallic cylinders on microstrip line” Electron. Lett., vol. 45, no. 8, pp. 415-417, Apr. 2009.
M. Dydyk, “Microstrip directional couplers with ideal performance via single-element compensation,” IEEE Trans. Microw. Theory Tech., vol. 47, no. 6, pp. 956–964, Jun. 1999.
R. Phromloungsri, M. Chongcheawchamnan, and I. D. Robertson, “Inductively compensated parallel coupled microstrip lines and their applications,” IEEE Trans. Microw. Theory Tech., vol. 54, no. 9, pp.3571–3582, Sep. 2006.
S. Lee, and Y. Lee, “A design method for microstrip directional couplers loaded with shunt inductors for directivity enhancement,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 4, pp. 994–1002, Apr. 2010.
M. Makimoto and S. Yamashita, “Bandpass filters using parallel coupled stripline stepped impedance resonators,” IEEE Trans. Microw. Theory Tech., vol. MTT-28, no. 12, pp. 1413-1417, Dec. 1980.
A. Worapishet, S. Srisathit, W. Surakumpontorn, “Stepped-Impedance coupled resonators for implementation of parallel coupled microstrip filters with spurious band suppression,” IEEE Trans. Microw. Theory Tech., vol. MTT-60, no. 6, pp. 1540-1548, Jun. 2012.
Advanced Design System (ADS) 2009. Agilent Technol., Palo Alto, CA, 2009. (http://www.agilent.com/find/eesof-ads)