2019 Volume 16 Issue 8 Pages 20190125
The substrate integrated waveguide (SIW) technology is promising in millimeter wave circuit design because of its low radiation loss and easy manufacturing. In this letter, an SIW filter with novel coupling-enhanced semicircle slots is presented. The coupling coefficients between resonators can be enhanced by 115% with a one-octave tuning range. To demonstrate the proposed concept, a 4-pole filter prototype is designed and fabricated. The measured results show excellent agreement with the simulated results.