220-to-330-GHz Manifold Triplexer With Wide Stopband Utilizing Ridged Substrate Integrated Waveguides

Abstract

This article reports a three-channel, noncontiguous, manifold multiplexer operating from 220 to 330 GHz, a 40% fractional operating bandwidth. The structure is designed and implemented using a set of ridged substrate integrated waveguides (SIWs). The ridged SIW improves the stopband bandwidth and reduces the overall structure size by 35% over a conventional SIW design. The triplexer utilizes an organic package substrate technology developed by Intel, featuring four thick copper metal layers and continuous trench vias in lieu of standard via fences, which significantly decrease the ohmic loss of the ridged SIW waveguides. Electromagnetic-circuit modeling and codesign techniques are adopted in the development of the triplexer structure. The fabricated triplexer is measured using banded millimeter-wave wafer probing and exhibits 37 dB of insertion loss in the passbands and better than 10 dB of average return loss for each of the channel filters. The measured stopband attenuation is better than 27 dB for all three channels.