Lightweight low-cost Ka-band 3-D printed slotted rectangular waveguide bandpass filters

This paper presents a lightweight Ka-band slotted rectangular waveguide bandpass filter that is fabricated using a fast and low-cost stereolithography-based 3-D printing technique. The filter is printed with a low-density ceramic-filled resin that features a much higher mechanical strength and a much better thermal handling capability than these properties of ordinary resin-based 3-D printing materials. The ceramic-resin-based filter exhibits a measured insertion loss of 0.23–0.5 dB in its passband 30.1–33.7 GHz, and a weight around 39% smaller than that of the filter with the same geometry but made from aluminum.