This letter presents a novel design for a 3-D-printed circular waveguide dual-mode (CWDM) filter with a modified cavity shape. The modification leads to a wide spurious-free stopband, which is highly desirable for channel separation in waveguide contiguous output multiplexers (OMUXs) in satellite communication systems. The new resonant cavity design is a result of applying shape deformation to a basic circular cavity in order to move away and suppress parasitic modes. A fourth-order Ku-band channel filter with two transmission zeros (TZs) is designed, fabricated by additive manufacturing (AM) in one piece and measured. In comparison with the state-of-the-art design of a stepped CWDM filter, an improvement of approximately 35% wider spurious-free range is achieved.

中文翻译：

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用于卫星通信系统的具有改进带外性能的圆形波导双模滤波器


这封信提出了一种新颖的 3D 打印圆形波导双模 (CWDM) 滤波器的设计，该滤波器具有改进的腔形状。这种修改产生了宽的无杂散阻带，这对于卫星通信系统中波导连续输出复用器 (OMUX) 的通道分离来说是非常理想的。新的谐振腔设计是将形状变形应用于基本圆形腔，以消除和抑制寄生模式。设计了一种具有两个传输零点 (TZ) 的四阶 Ku 波段通道滤波器，通过增材制造 (AM) 一体制造并进行了测量。与阶梯式 CWDM 滤波器的最先进设计相比，无杂散范围提高了约 35%。