In this paper, Ultra-Wideband (UWB) filters at 6–18GHz are designed that can reduce undesired frequency responses at lower and upper frequency bands to less than −20dB. Arbitrary load impedances are considered in the design of these filters. The structure of these filters is the combination of microstrip band-pass filters and Defected Ground Structures (DGSs) with multiple sections. The optimum circuit dimensions are calculated using a computer code which implements the Least Mean Squares (LMS) optimization method. Two design examples are included to illustrate this method. In these examples, eight-section DGS structures are employed to eliminate the unwanted upper frequency band responses. To ensure the correct performance of the designed filters, they are analyzed using full-wave methods and fabrication and the results of the measurement or full-wave analysis shows good agreement with the results of the computer code and the circuit model simulations.

中文翻译：

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设计 6–18 GHz 微带滤波器，去除不需要的上下频带频率响应和任意负载阻抗匹配

在本文中，超宽带 (UWB) 滤波器在 6–18GHz 的设计可以将较低和较高频段的不希望的频率响应降低到小于-20D b。在这些滤波器的设计中考虑了任意负载阻抗。这些滤波器的结构是微带带通滤波器和具有多个部分的缺陷接地结构 (DGS) 的组合。使用实现最小均方 (LMS) 优化方法的计算机代码计算最佳电路尺寸。包括两个设计示例来说明这种方法。在这些示例中，采用八段 DGS 结构来消除不需要的上频带响应。为了确保所设计滤波器的正确性能，使用全波方法和制造对其进行分析，测量或全波分析的结果与计算机代码和电路模型模拟的结果非常吻合。