A compact double-sided contactless electromagnetic bandgap (DCEBG) structure is introduced in this letter. It consists of three metal plates placed in parallel, including two smooth metal plates and a corrugated metal plate in the middle. The middle plate is double-sided corrugated alternatively with a displacement of half period. The depth of the corrugations is about quarter wavelength of center frequency of its stopband. The thickness of the proposed DCEBG is slightly thicker than the depth of the corrugations. A double-sided contactless waveguide flange (CWF) based on the DCEBG is proposed. Compared with the back-to-back CWF in the form of bed of nails, the thickness is effectively reduced. A prototype of the double-sided CWF (DCWF) suited for standard WR75 waveguide is designed, manufactured, and tested. The measured insertion loss is less than 0.048 dB and the return loss is lower than 25 dB over the entire WR75 waveguide frequency band.

中文翻译：

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双面非接触波导法兰的紧凑型波纹板

在这封信中介绍了一种紧凑的双面无接触电磁带隙（DCEBG）结构。它由三个平行放置的金属板组成，其中包括两个光滑的金属板和一个中间的波纹金属板。中间板是双面波纹状的，间隔时间为半周期。波纹的深度约为其阻带中心频率的四分之一波长。提出的DCEBG的厚度略大于波纹的深度。提出了一种基于DCEBG的双面无接触波导法兰（CWF）。与钉床形式的背靠背CWF相比，厚度得到了有效减小。设计，制造和测试了适用于标准WR75波导的双面CWF（DCWF）原型。