A Ka-band Filter Based on the Quarter-height Pin Gap Waveguide with Improved Reliability

This paper presents a Ka-band bandpass filter based on the quarter-height pin gap waveguide which is proposed to enhance manufacturing efficiency and the structure reliability by reducing the pin height of the traditional gap waveguide to a quarter height and reducing the air gap to close to zero. And the quarter-height pin gap waveguide provides a wider stopband due to the reduced air gap. The transmission line and resonator based on the quarter-height pin gap waveguide are studied to reveal the advantages of the quarter-height pin gap waveguide over the traditional gap waveguide and the half-height pin gap waveguide. A Ka band filter with a 2% FBW and a 0.3 dB insertion loss is designed and simulated in CST to verify the proposed design.