Novel Designs of Slot Array Antenna for 100 GHz Applications Using Gap Waveguide Technology

Doctoral thesis, 2025

Frequencies around 100 GHz offer considerable potential for the next generation of wireless communication systems due to the abundant, yet underutilized spectral resources available. At such high frequencies, high-gain array antennas with low-loss capability are essential to compensate for the substantial free-space path loss.
Waveguide slot array antennas, owing to their low loss, high mechanical strength, and robust power-handling capabilities, present a promising solution at 100 GHz. In addition, recent advancements in gap waveguide (GWG) technology have made it easier to fabricate slot arrays at high frequencies. Building upon the traditional slot array designs and incorporating GWG, this thesis proposes two novel slot array configurations to improve antenna performance in multiple aspects.
First, a wide-scanning slot array at 100 GHz based on GWG is introduced. By leveraging a novel decoupling technique, the proposed design enables an all-metal longitudinal slot array to achieve ±60° wide-angle scanning in the E-plane for the first time, with a 3-dB scan loss and a total efficiency exceeding 91%. Second, a dual-band filtering slot array based on GWG is presented, operating at 74–78 GHz and 102–106 GHz. The main novelty of this design lies in its common waveguide channels for dual-band slot excitation and a truly shared planar aperture, enabling both broadside radiation and independent multi-channel operation.
These proposed designs provide new insights into slot array antenna design and show promising potential for future applications in 100 GHz communication systems.