X波段叠层片式微带铁氧体环行器的设计

采用叠层片式化设计有望实现微波环形器与低温共烧陶瓷(LTCC)技术的结合。借助三维电磁仿真手段设计了一种X波段微带铁氧体环行器，基片采用具有不同饱和磁化强度的旋磁材料构成叠层片式结构。研究结果表明，叠片数目及其饱和磁化强度的搭配对环形器的回波损耗和隔离度特性影响显著，这与叠层结构引入的界面及叠片变化的饱和磁化强度影响了环形器的等效输入电路参数有关。通过优化设计，可以获得具有高回波损耗、高隔离度及低插入损耗等优良性能的器件，但带宽受叠片数目及其饱和磁化强度的搭配影响较小，难以通过优化进行拓展。

Design of X band multilayer chip microstrip ferrite circulator

The microwave circulator is expected to be integrated with low temperature co-fired ceramics (LTCC) technique by multilayer chip structure design. In this paper, the X band microstrip ferrite circulator is designed with the three-dimensional electromagnetic simulation method. The whole substrate consists of gyrotropic stack layers, which provides different saturation magnetization. The results show that the stack number and saturation magnetization of the stack layers exhibit considerable effect on the return loss and reverse isolation for the circulator. It suggests to be correlated with the input equivalent circuit parameters for the circulator, which are affected by the interface and varied saturation magnetization of the stack layers in multilayer chip structure. High return loss, high reverse isolation and low insertion loss can be obtained with the optimized design. However, it is found that the bandwidth of the circulator is unaffected by the stack number and saturation magnetization of the stack layers, which is difficult to be improved with the optimized design.