volume | PIER Journals

Abstract

This paper presents the first coupled-line coupler that provides independent power division ratios at dual bands. In contrast with previous dual-band coupled-line couplers, the power division ratios k²(f₂) and k²(f₂) at each band (f₁ and f₂) can be independently controlled in order to satisfy the requirements of various communication protocols at different bands. Moreover, it has a compact size due to the usage of coupled lines rather than transmission lines. Explicit design equations and design guide of the coupler are provided. In this letter, one prototype of the proposed coupler is simulated, fabricated, and measured. It provides power division ratios k²(f₁)=4 dB at f₁=1 GHz and k²(f₂)=8 dB at f₂=2.4 GHz. The measured result agrees well with the simulation.

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Dr. Siyue Zhou

Dr. Xiaochuan Shen

Prof. Yongle Wu

Dr. Yuan'an Liu