An ultrawideband absorptive common-mode filter (A-CMF) with a newly developed defected ground structure (DGS) is proposed in this article. The DGS miniaturized to a subwavelength size is able to totally suppress the common-mode noise while maintaining the signal integrity of the differential mode. In addition, the reflection and radiation of the common-mode noise are negligible in the stopband. For quick design, a simplified equivalent circuit model is also proposed. This model can be employed to estimate the resistances of the lumped resistors embedded in the DGS to obtain a very wide absorption band. In the demonstrated example, the fractional bandwidth determined by a 90% absorption efficiency can achieve as large as 104% around 3.55 GHz for an A-CMF realized on a simple two-layer printed circuit board. Such a widely absorptive bandwidth is never achieved before to our knowledge. The design methodology is validated by full-wave simulation. Finally, real measurement of the design is also carried out to confirm the design and analysis.

中文翻译：

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一种新颖的超宽带吸收共模滤波器设计，采用小型化和电阻式变形接地结构

本文提出了一种具有最新开发的缺陷接地结构（DGS）的超宽带吸收共模滤波器（A-CMF）。小型化至亚波长尺寸的DGS能够完全抑制共模噪声，同时保持差模的信号完整性。此外，在阻带中，共模噪声的反射和辐射可以忽略不计。为了快速设计，还提出了简化的等效电路模型。该模型可用于估计DGS中嵌入的集总电阻的电阻，以获得非常宽的吸收带。在演示的示例中，对于在简单的两层印刷电路板上实现的A-CMF，由90％的吸收效率决定的分数带宽可以在3.55 GHz左右达到104％。就我们所知，如此宽的吸收带宽从来没有达到过。通过全波仿真验证了设计方法。最后，还对设计进行了实际测量，以确认设计和分析。