A novel dual-mode (DM) dielectric waveguide (DW) filter with controllable transmission zeros (TZs) is presented. The DM filter is based on a cascaded implementation, utilizing individual DM DW cavities. The filter is practically realized by embedding three circular blind holes at different positions in the surface of a dielectric silver-coated square cavity. By changing the relative position of the blind holes or rotating the direction of the proposed DW cavity, the filter’s TZs’ frequency locations can be flexibly adjusted. The zero points can be set in frequency at the low end of the passband, at the high end of the passband, or they can be generated at both the low and high ends of the passband in order to improve the selectivity of the filter. In this study, the two-cavity fourth-order filter is taken as an example, and the experimental results validate the feasibility of the presented theoretical design.

中文翻译：

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具有可控制的传输零点的双模介电波导滤波器

提出了一种新型的双模（DM）介电波导（DW）滤波器，该滤波器具有可控的传输零位（TZ）。DM滤波器基于级联实施，利用各个DM DW腔体。该滤波器实际上是通过在电介质镀银方腔表面的不同位置嵌入三个圆形盲孔来实现的。通过改变盲孔的相对位置或旋转建议的DW腔的方向，可以灵活地调整滤波器的TZ的频率位置。零点可以在通带的低端，通带的高端设置频率，或者可以在通带的低端和高端同时生成零点，以提高滤波器的选择性。在本研究中，以二腔四阶滤波器为例，