太赫兹科学与电子信息学报, 2017, 15 (2): 187, 网络出版: 2017-06-06
太赫兹液晶反射阵列移相单元的设计与分析
Design and analysis of Liquid Crystal-based reflectarray phase shifting cells in THz band
摘要
为了满足高增益天线大的移相度和可工作在太赫兹频段,设计了一种基于液晶的双偶极子反射移相单元结构。采用液晶的等效介电常数模型,在频率为 335~345 GHz频段均产生 360o以上的相移,在 342 GHz实现最大相移 390o。为了减小液晶不均匀性对相移产生的影响,建立了单元的精确模型,该模型在频率范围为 330~338 GHz时均产生了 250o以上的相移,在336 GHz实现最大相移285o。与均匀液晶等效介电常数模型相比,产生最大相移的频率点发生了变化,并且产生了最大为105o的移相差值,这在相控反射阵列天线的设计中是不可忽略的。
Abstract
In order to make the high-gain antenna have a large phase shift and can work in the THz band, a reflectarray element based on Liquid Crystals(LC) is designed to operate in the frequency range from 270 GHz to 390 GHz. When the phases of reflectarray element are calculated with a constant value of the permittivity, the elements produce a dynamic phase range above 360o in 335-345 GHz, and achieve the maximum 390o at 342 GHz. Then, in order to reduce the influence of liquid crystal inhomogeneity on the phase shifting, an accurate model of liquid crystal-based reflectarray cells is established. The accurate modeling produces a dynamic phase range above 250o in 330-338 GHz, and achieves the maximum 285o at 336 GHz. Compared with the equivalent permittivity modeling, the accurate modeling has a maximum phase error of 105o, which cannot be ignored in the reconfigurable reflectarray antennas design.
葛忆, 夏天雨, 杨军, 邓光晟, 尹治平, 桑磊. 太赫兹液晶反射阵列移相单元的设计与分析[J]. 太赫兹科学与电子信息学报, 2017, 15(2): 187. GE Yi, XIA Tianyu, YANG Jun, DENG Guangcheng, YIN Zhiping, SANG Lei. Design and analysis of Liquid Crystal-based reflectarray phase shifting cells in THz band[J]. Journal of terahertz science and electronic information technology, 2017, 15(2): 187.