Analysis of Radiating Transverse Slot Unit Cell and Reflection Cancellation at D-Band

The paper presents an analysis, design guidelines, and proposes a design for a transverse slot in a parallel plate waveguide (PPWG) configuration. It aims to study radiation coupling and reflections at the radiating slot. It also aims to propose a design of a unit cell for cancellation of reflections near the coupling slot to relax fabrication constraints at sub-THz frequencies. The study employed simulations in commercial software CST to investigate the design. The analysis revealed that coupling levels vary based on different widths of the radiating transverse slot (RTS). Additionally, the proposed design with an edge reflection cancellation notch successfully canceled reflections near the coupling slot, making it suitable for manufacturing at sub-THz frequencies. The array of these RTS unit cells can provide a directive beam with high efficiency when excited with proper phase and amplitude. Precise knowledge of the characteristics of the RTS unit cell is beneficial in the design of a planar array for the desired gain, radiation pattern, low side lobes, and improved matching.