A Reconfigurable Broadband Polarization Converter Based on an Active Metasurface
A Reconfigurable Broadband Polarization Converter Based on an Active Metasurface
复制标题
基于有源超表面的可重构宽带偏振转换器
DOI：
10.1109/tap.2018.2866636
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发表时间：
2018-11-01
影响因子：
5.7
通讯作者：
Cui, Tie Jun
中科院分区：
文献类型：
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作者：
Gao, Xi;Yang, Wan Li;Cui, Tie Jun
我们提出了一种有源超颖表面，其功能可以动态切换之间的线性到线性，线性到椭圆，线性到圆偏振转换在宽带。有源超颖表面由嵌入压控变容二极管的蝶形单元组成。通过控制变容二极管的偏置电压，可以定制所提出的超颖表面的电磁响应，从而实现可重构的极化转换。仿真结果表明，在无偏置电压的情况下，该超表面能够在3.9 ~ 7.9 GHz的频率范围内将线极化波反射为交叉极化波，极化转换率超过80%;而在-19 V的偏置电压下，该超表面在4.9 ~ 8.2 GHz的宽带范围内被调谐为圆极化转换器。此外，沿沿着<inline-formula><tex-math notation="LaTeX">$x$</tex-math></inline-formula>-和<inline-formula><tex-math notation="LaTeX">$y$</tex-math></inline-formula>-方向的两个等效电路的开发阐明的可调机制。实验结果与商业软件和等效电路模型的仿真结果吻合较好。
We propose an active metasurface whose functionalities can be dynamically switched among linear-to-linear, linear-to-elliptical, and linear-to-circular polarization conversions in a wideband. The active metasurface is composed of butterfly-shaped unit cells embedded with voltage-controlled varactor diodes. By controlling the bias voltage of the varactor diodes, the electromagnetic responses of the proposed metasurface can be tailored, leading to reconfigurable polarization conversions. The simulation results reveal that with no bias voltage, the proposed metasurface is able to reflect linear-polarization waves to cross-polarization waves in the frequency range from 3.9 to 7.9 GHz, with a polarization conversion ratio of over 80%; however, at the bias voltage of −19 V, the metasurface is tuned to be a circular polarization converter in a wideband from 4.9 to 8.2 GHz. Moreover, two equivalent circuits along the <inline-formula> <tex-math notation="LaTeX">$x$ </tex-math></inline-formula>- and <inline-formula> <tex-math notation="LaTeX">$y$ </tex-math></inline-formula>-directions are developed to elucidate the tunable mechanism. The experimental results are in a good agreement with the simulation results obtained from commercial software and from the equivalent circuit model.