A novel out-of-plane integration of multilayer strip-resonators is proposed. This kind of structure retains the merit of traditional in-plane integrated ones – simple and compact-sized, meanwhile, achieves the same amount of coupling with smaller horizontal space between resonators. Further miniaturisation of the previous bandpass filters (BPFs) can be realised by re-designing them based on the proposed structure. This Letter gives an example of an S-band BPF. A 52.4% size reduction is achieved by out-of-plane integration of resonators, while maintaining a comparable performance to the previous in-plane integrated design.

中文翻译：

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多层带状谐振器的面外集成及其应用

提出了一种新颖的多层条形谐振器的平面外集成。这种结构保留了传统平面集成结构的优点——简单、紧凑，同时实现了相同的耦合量，谐振器之间的水平空间更小。通过基于所提出的结构重新设计先前的带通滤波器 (BPF)，可以进一步小型化它们。这封信给出了一个 S 波段 BPF 的例子。通过谐振器的面外集成实现了 52.4% 的尺寸减小，同时保持了与之前的面内集成设计相当的性能。