The Slotted Waveguide Array Antenna with Reflection Canceling Stairs in Millimeter Waveband

We propose and design 38-GHz slotted waveguide antenna with reflection canceling stairs to improve aperture efficiency. The waveguide includes 10 linearly arranged slots and 9 stairs. From the Finite Element Method (FEM) calculation, length and offset of each slot are optimized to obtain uniform radiation intensity. Then the corresponding stair position and height are designed to suppress the reflection. The simulation of the full model confirms that aperture efficiency is improved to 64.9%.