A Novel Bandwidth Reconfigurable Waveguide Filter for Aerospace Applications

This letter presents a novel configuration of a high-Q bandwidth (BW) reconfigurable waveguide (WG) filter tuned with only two tuning elements regardless of the filter order. The filter is realized in rectangular WG technology and is capable to tune the BW without deviating the center frequency. Furthermore, the configuration is scalable to higher order filters without the need for additional tuning mechanisms. For the proof of concept, a four-pole prototype filter is designed, fabricated, and tested at the Ku-band. The measured BW tunability of the filter is nearly 35% from 225 to 320 MHz. The center frequency remains unaltered at 13.375 GHz over the BW range.