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Progress In Electromagnetics Research Letters
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MINIATURIZATION OF BROADBAND 3-DB BRANCH-LINE COUPLER

By J. Zhu, Y. Zhou, and J. Liu

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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:
J. Zhu, Y. Zhou, and J. Liu, "Miniaturization of Broadband 3-dB Branch-Line Coupler," Progress In Electromagnetics Research Letters, Vol. 24, 169-176, 2011.
doi:10.2528/PIERL11051706

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