In this letter, a miniaturized half-mode fan-shaped substrate integrated waveguide (HMFSSIW) resonator is proposed to form different order of filters without increasing the size. The resonator is based on a semicircular substrate integrated waveguide (SIW) cavity with metallized vias distributed along the circumference. A metallized via located on the circle center and a semicircular ring slot etched along the circumference to realize half-mode resonances. By introducing one or two radial slots with different lengths, the four half-mode resonant frequencies can be controlled independently, which enables to form second- or third-order filter with controllable bandwidth and wide stopband. Finally, a second-order Chebyshev filter is well designed and a third-order filter centered at 1 GHz with a fractional bandwidth of 15% and a transmission zero (TZ) on the right side is designed, fabricated, and measured. The measured results show good agreement with the simulated ones.

中文翻译：

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具有可扩展阶数和宽阻带的小型化半模扇形 SIW 滤波器

在这封信中，提出了一种小型化的半模扇形基板集成波导（HMFSSIW）谐振器，以在不增加尺寸的情况下形成不同阶的滤波器。谐振器基于半圆形衬底集成波导 (SIW) 腔，带有沿圆周分布的金属化过孔。位于圆心的金属化通孔和沿圆周蚀刻的半圆形环槽以实现半模谐振。通过引入一个或两个不同长度的径向槽，可以独立控制四个半模谐振频率，从而形成带宽可控、阻带宽的二阶或三阶滤波器。最后，二阶切比雪夫滤波器设计良好，设计、制造和测量了以 1 GHz 为中心、分数带宽为 15% 且传输零 (TZ) 位于右侧的三阶滤波器。测量结果与模拟结果吻合良好。