In this letter, a novel folded ridge substrate-integrated waveguide (FRSIW) is proposed by folding a classic ridge substrate-integrated waveguide (RSIW). The FRSIW demonstrates a size nearly half of its RSIW counterpart while keeping the main propagation properties of the RSIW. A prototype of the wideband FRSIW filter with compact size has been designed and tested. The measurements show that the proposed wideband FRSIW filter has the advantages of low loss, compact size, and easy fabrication and integration with other electronic systems.

中文翻译：

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紧凑型宽带折叠脊基板集成波导滤波器

在这封信中，通过折叠经典的脊形衬底集成波导 (RSIW) 提出了一种新型折叠脊形衬底集成波导 (FRSIW)。FRSIW 的大小几乎是其 RSIW 对应物的一半，同时保持了 RSIW 的主要传播特性。已经设计并测试了具有紧凑尺寸的宽带FRSIW滤波器的原型。测量结果表明，所提出的宽带 FRSIW 滤波器具有损耗低、尺寸紧凑、易于制造和与其他电子系统集成等优点。