阻抗匹配器级数对铁电体移相器性能的影响

Impact of Different Impedance Matching Network on Performance of Ferroelectric Phase Shifter

针对铁电体透镜式移相器的阻抗失配问题,分别采用3级、4级和5级的1/4波长阻抗匹配器结构,对铁电体移相器进行阻抗匹配调试仿真。通过对比不同匹配级数的匹配效果,最终确定了4级的匹配方案,并通过进一步优化器件结构,设计出的铁电体移相器在X频段内可实现360°相移,驻波比在主带宽内小于1.2,反射系数大于20 dB,中心频率处反射系数达到40 dB,信号传输系数在低频处小于1.1 dB,在高频处为1.5 dB,实现了铁电体移相器较好的阻抗匹配。

To solve the impedance mismatch problem of the ferroelectric lens phase shifter, the matching network using three transformers, four transformers and five transfoimers is adopted to match the ferroelectric phase shifter. Comparing the results of different match networks, the matching network using four transformers is the best. By optimizing the structure of the device, finally the ferroelectric phase shifter can obtain a phase shift of 360°at X band, voltage standing wave ratio in the main band width is less than 1.2, the reflection coefficient is larger than - 20 dB, and in the central frequency is - 40 dB, the signal transmission coefficient is less than - 1.1 dB at the low frequency point, and - 1.5 dB at the high frequency point, and the impedance mismatch problem of the ferroeleetric phase shifter is solved.