volume | PIER Journals

Abstract

A novel ultra-wideband (UWB) coupled-line coupler with an operating frequency band from 2 to 22 GHz is presented in this article. The proposed coupler is composed of six coupled-line sections. The continuous zigzag capacitive compensation (CZCC) technology is used to broaden the operation frequency band, which also significantly enhances the isolation and return losses of the coupler. The coupler is built on a multilayer circuit structure. In order to improve the design accuracy of the three-dimensional circuit structure, the combination simulation of EM simulator and circuit simulator are employed. The simulated and measured results of the UWB 10 dB asymmetric directional coupler are presented and discussed, which demonstrate that it is practical to achieve good performances in such a circuit structure.

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Dr. Hongyan Li

Dr. Jun Zhu

Dr. En Li