Different strategies for the additive manufacturing of slotted slant ridge filtering doublet

In this paper, the slotted slant ridge resonator together with different strategies for their manufacturing with 3D printing technology is illustrated. The slant ridge resonator consists of a ridge with a slot inserted in a rectangular waveguide. Both ridge and slot resonant modes are exploited to obtain a second order filter response (doublet) capable of two poles and two transmission zeros. The structure allows an excellent control in terms of both bandwidth and transmission zero positioning.The manufacturing strategies considered in the paper consists in the 3D printing of the slotted ridge with different supports. Ridge and support are then electroplated and finally inserted in a metallic rectangular waveguide ensuring the metal contact between support and waveguide. Measured results demonstrating the feasibility of the method are shown