1-D Wide Scanning Gap Waveguide-Based Slot Array Antenna Using Decoupling Technique for 100 GHz Applications

This article presents a 1-D wide scanning slot array antenna based on a ridge gap waveguide (RGW), operating at a 100-GHz band. A novel half-wall decoupling structure is proposed to reduce the mutual coupling and the reflection coefficient simultaneously, thus achieving a more stable active reflection coefficient (ARC) within the ±60° scanning range. At the same time, special attention has been given to retaining the embedded pattern suitable for wide scanning performance. An eight-element slot array antenna ( $8\times8$ slots) with two different feeding networks is fabricated and measured to verify the scanning performance. The prototype achieves 91% total efficiency while scanned up to 60° with 3-dB scanning loss. The measured results show good agreement with the simulations both for the reflection coefficient and radiation performance.