Efficiency of 76GHz Post-Wall Waveguide-Fed Parallel Plate Slot Arrays

We design and fabrcae ous sizes of 76GHIz post-wall waveguide-fed parallel plate slot arrays. The post-wall waveguide is an array of mealiz via-holes with a narrow a grounded dielectric substrate. The antenna can be easily mad at low cost by convenional PCB (printed circuit board) fabrication techniques such as via-holing, metal plating and etching We have obtained 40 - 50% efficiency for various sizes from 26 × 24 mm to 104 × 100 mm We have measured 35.3dBi gain with 39.3% efficiency at 77.0GHz in an sized 104 × 100 mm.