This letter presents the design of compact triple- and quad-band power dividers (PDs) based on substrate integrated waveguide (SIW) technology. The proposed PDs are designed as a rectangular cavity, one pair of unequal complementary split-ring resonators (CSRRs) and U-shaped slots (USSs). Initially, a dual-frequency SIW PD is implemented using unequal CSRRs on the top surface of the SIW cavity. This dual-frequency PD is converted into triple-band and quad-band operations by employing USSs on the bottom surface of the cavity. The center frequencies of the proposed PDs are controlled by varying the dimensions of CSRRs and USS. To demonstrate the proposed concept, triple- and quad-band PDs are designed, fabricated, and tested. The measured responses are very much consistent with the simulated one. The overall sizes of the proposed triple- and quad-band PDs are $0.03\lambda _{g} ^{2}$ and $0.02\lambda _{g} ^{2}$ , respectively. The proposed PDs feature compact size, triple- and quad-band operation, good return loss, and isolation.

中文翻译：

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基于紧凑型基片集成波导的三频和四频功率分配器的设计

这封信介绍了基于衬底集成波导（SIW）技术的紧凑型三频和四频功率分配器（PD）的设计。提出的PD设计为矩形腔，一对不相等的互补开口环谐振器（CSRR）和U形槽（USS）。最初，在SIW腔的顶面上使用不相等的CSRR来实现双频SIW PD。通过在腔体底表面上采用USS，可以将这种双频PD转换为三频和四频操作。通过更改CSRR和USS的尺寸，可以控制提议的PD的中心频率。为了演示所提出的概念，设计，制造和测试了三频段和四频段PD。测得的响应与模拟响应非常一致。 $ 0.03 \ lambda _ {g} ^ {2} $ 和 $ 0.02 \ lambda _ {g} ^ {2} $ ， 分别。拟议的PD具有紧凑的尺寸，三频和四频操作，良好的回波损耗和隔离性。