volume | PIER Journals

Abstract

A miniaturized rat-race coupler with arbitrary power division ratio is proposed in this paper. The design formulas of the rat-race coupler with arbitrary power division ratio are derived using the even-odd decomposition analysis. The proposed structure demonstrates miniaturized size and perfect isolation due to adding phase inverter to the branch. For demonstration, a 20 dB rat-race coupler operating at 1 GHz with 81.34% size reduction is designed and fabricated. There is good agreement between measured and simulated results.

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Dr. Xiao Yang

Dr. Zhenheng Liao

Dr. Xu-Chun Zhang