一种用于X波段T/R组件的小型化高平坦度耦合器设计

摘要

To satisfy the requirements of calibration and correction for X⁃wave⁃band T/R assembly,in which small⁃size and high performance coupler should be integrated. In weak coupling condition,the microstrip⁃to⁃stripline multi⁃order hole⁃coupler has the advantages of flat coupling characteristic,small size and easy to integrate with radio frequency active circuits. This cou⁃pler is convenient to realize on LTCC multi⁃layer basic⁃plate of T/R assembly. In design process,firstly the number of the holes and their distribution features are determined according to the hole⁃coupling basic theory and formula. Then in combination with the restriction of actual layout,the parameterized model is established in the electromagnetic field simulation software HFSS. Finally the optimal physical parameter can be acquired by tuning and optimization in HFSS. The simulation results indicate that the coupler′ dimension is less than λ0 4, and the flatness in band is better than ±0.1 dB. This coupler has reached the design requirements,and can be widely used in X⁃wave⁃band miniaturization T/R assembly.%为满足X波段T/R组件定标和校正的需求，组件内部需集成小型化、高性能的耦合器。微带到带状线多阶小孔耦合器在弱耦合情况下具有宽带平坦的耦合特性、体积小、易于与射频有源电路集成，非常方便在T/R组件的LTCC多层基板上实现。在设计过程中，首先根据多阶小孔耦合的基本理论和公式确定小孔的数量和分布特征，再依据实际布局的限制在电磁场仿真软件HFSS中建立参数化模型，最后通过HFSS的调谐优化确定最优的物理参数。仿真表明，该耦合器尺寸小于λ04，带内平坦度优于±0.1 dB。该耦合器完全达到设计要求，可广泛应用于X波段小型化宽带T/R组件中。