基于缺陷地慢波传输线结构的液晶移相器设计

为了实现低插损、大相位覆盖范围的加载缺陷地结构(DGS)的微带线液晶移相器,利用 HFSS仿真软件对 DGS微带线液晶移相器进行建模和仿真,通过改变DGS的形状来改变单个移相单元的色散特性,提升单个单元的移相能力,从而减少移相单元的使用数量,降低移相器传输线整体插损。以哑铃型DGS的液晶微带线移相器作为参考标准,比较了5种形状的DGS(哑铃型、减少DGS面积、一阶分形、三角形、交叉型)的移相能力和插损差异。仿真结果表明:下一阶分形和交叉型DGS微带线液晶移相器移相能力较好,最后对不同介电常数的移相器进行仿具观察其S 参数和移相能力,进一步验证了这一结果。

A Microstrip Line Liquid Crystal Phase Shifter Based on Defective Ground Structure Slow Wave Structure

In order to make a microstrip line liquid crystal phase shifter loaded with defective ground structure(DGS) good in performance, small in insertion loss, suitable in return loss, and larger in phase coverage.the DGS microstrip line liquid crystal phase shifter is modeled and simulated by utilizing HFSS simulation software for changing the phase shifting capability of a single phase shifting unit and changing the shape of the DGS, achieving the same performance with fewer phase shifting units. Taking a dumbbell DGS liquid crystal microstrip line phase shifter as a reference, the differences in phase shifting capability and insertion loss of five shapes of DGS (dumbbell, reduced DGS area, first-order fractal, triangular, and crossover) are compared. The first-order fractal and crossover DGS microstrip line liquid crystal phase shifters show that the phase shifting is good in capability in comparison, and finally the results are verified by simulating phase shifters with different dielectric constants to observe their S-parameters and phase shifting capability