基于加载线型的平面太赫兹移相器设计

Design of a planar terahertz phase shifter based on loaded microstrip-line

摘要:

移相器是相控阵系统中的重要组成器件，随着频率的增加，金属的趋肤深度及波导表面粗糙度对器件的影响不可忽略，会使移相器的损耗增加。对此，提出一种基于加载线型的平面太赫兹移相器。将2个枝节并联在微带线上，在并联枝节上加载开关二极管，调节两段枝节的电长度得到所需的移相量；控制开关的导通和断开，实现不同的移相角度。仿真结果表明，在192~210 GHz频带范围内，导通和断开的反射系数都小于-10 dB，插入损耗小于0.5 dB，移相误差小于5°，其中在5 GHz带宽范围内，移相误差小于1°。提出的平面型移相器，加工容易，成本低，便于系统集成化，在太赫兹相控阵系统中具有广泛的应用前景。

Abstract:

Phase shifters are important devices in phased array systems. As the frequency increases, the skinning depth of the metal and the roughness of the waveguide surface have a non-negligible effect on the device, which cause the increase o f device loss. To address the difficulties of poor phase shift accuracy and high loss in terahertz phase shifters, a planar digital terahertz phase shifter based on a loaded line is proposed. By connecting two branches in parallel on a microstrip line, the switching diodes are loaded on the parallel branches, the electrical lengths of the two branches are adjusted to obtain the desired phase shift, and the switches states are controlled to achieve different phase shift angles. The simulation results show that the reflection coefficients of both on and off are less than -10 dB, the insertion loss is less than 0.5 dB, and the phase shifting error is less than 5° in the 192~210 GHz band range, while the phase shifting error is less than 1°within the 5 GHz band. The proposed planar phase shifter is easy for processing and system integration with low cost, and has a wide range of applications in terahertz phased array systems.