Vol. 24

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2011-06-16

Miniaturization of Broadband 3-dB Branch-Line Coupler

By Jun Zhu, Yonggang Zhou, and Jianhua Liu
Progress In Electromagnetics Research Letters, Vol. 24, 169-176, 2011
doi:10.2528/PIERL11051706

Abstract

In this letter, a new miniaturized broadband 3-dB branch-line coupler at the center frequency of 880 MHz is proposed. The proposed coupler is designed by means of integrated miniaturization method, which consists of shunt capacitors, fractal geometry and equivalent miniaturized stubs, to achieve 82% size reduction compared with the referenced coupler. The return loss and isolation are both under -20 dB over a 19% relative bandwidth. The proposed coupler is simulated, fabricated and measured. The measured results agree well with the simulated ones.

Citation


Jun Zhu, Yonggang Zhou, and Jianhua Liu, "Miniaturization of Broadband 3-dB Branch-Line Coupler," Progress In Electromagnetics Research Letters, Vol. 24, 169-176, 2011.
doi:10.2528/PIERL11051706
http://jpier.org/PIERL/pier.php?paper=11051706

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