This letter presents a planar mode composite folded substrate integrated waveguide (MCFSIW) that enables simultaneous propagation of the TE ₁₀ and folded TE ₁₀ (FTE ₁₀ ) modes. By adjusting the gap width of the MCFSIW, the cutoff frequency of the FTE ₁₀ mode can be tuned to be the same as that of the TE ₁₀ mode. The operation principle and propagation properties of the MCFSIW are analyzed. To excite the two modes independently, a simple joint feeding network (JFN) with a wide bandwidth and a high isolation is designed. A prototype of the MCFSIW with JFNs is fabricated and measured, and the measured results agree well with the simulations. The proposed MCFSIW is attractive in the development of multifunction and parallel data transmission systems.

中文翻译：

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模复合折叠基板集成波导

这封信介绍了一种平面模式复合折叠基板集成波导 (MCFSIW)，它能够同时传播 TE ₁₀和折叠 TE ₁₀ (FTE ₁₀ ) 模式。通过调整 MCFSIW 的间隙宽度，可以将 FTE ₁₀模式的截止频率调整为与 TE _10相同模式。分析了MCFSIW的工作原理和传播特性。为了分别激发这两种模式，设计了一个具有宽带宽和高隔离度的简单联合馈电网络（JFN）。制作并测量了带有 JFN 的 MCFSIW 原型，测量结果与模拟结果非常吻合。所提出的 MCFSIW 在开发多功能和并行数据传输系统方面具有吸引力。