In this paper, a ultra-wideband (UWB) bandpass filter with stopband characteristics is presented using a multi-mode resonator (MMR) technique. An MMR is formed by loading three dumbbell-shaped (Mickey and circular) shunt stubs placed in the center and two symmetrical locations from ports, respectively. Three circular and arrowhead defected ground structures on the ground plane are introduced to achieve UWB bandwidth with a better roll-off rate. The proposed filter exhibits stopband characteristics from 10.8 to 20 GHz with a 0.4 dB return loss. The group delay and roll-off rate of the designed filter are <0.30 ns in the passband and 16 dB/GHz at lower and higher cut-off frequencies, respectively. The dimension of the filter is 0.74λg × 0.67λg mm2 and was fabricated on a cost-effective substrate. All simulated results are verified through the experimental results.

中文翻译：

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利用 MMR 技术设计与分析具有阻带特性的平面 UWB 带通滤波器

在本文中，使用多模谐振器 (MMR) 技术提出了一种具有阻带特性的超宽带 (UWB) 带通滤波器。MMR 是通过分别加载放置在中心和两个对称位置的三个哑铃形（米奇和圆形）分流短截线形成的。在接地平面上引入了三个圆形和箭头缺陷接地结构，以实现具有更好滚降率的 UWB 带宽。所提出的滤波器具有 10.8 至 20 GHz 的阻带特性，回波损耗为 0.4 dB。所设计滤波器的群延迟和滚降率在通带中小于 0.30 ns，在较低和较高截止频率下分别为 16 dB/GHz。过滤器的尺寸为 0.74λG× 0.67λG毫米2并且是在具有成本效益的基板上制造的。通过实验结果验证了所有模拟结果。