SLM Printed Waveguide Dual-Mode Filters With Reduced Sensitivity to Fabrication Imperfections

This letter presents an eighth-order dual-mode waveguide filter, fabricated using the selective laser melting (SLM) technique. The filter employs four dimpled ellipsoid resonators, operating at fundamental TM101 mode. During printing, can be mechanically self-supported without any internal supports. Compared to filters employing tuning posts, proposed is less sensitive fabrication errors in terms of their impacts on passband return loss (RL), frequency shift, and bandwidth. was demonstrated WR-112 band (7–10 GHz), with a measured insertion 0.25–0.4 dB RL >15 across 8–8.46 GHz.