High-gain S-band slotted waveguide antenna arrays with elliptical slots and low sidelobe levels

Slotted waveguide antenna arrays ofier clear advantages in terms of their design, weight, volume, power handling, directivity and e-ciency. Slots with rounded corners are more robust for high power applications. This paper presents a slotted waveguide antenna with ellip- tical slots made to one broadwall of an S-band rectangular waveguide. The antenna is designed for operation at 3GHz. The slots length and width are optimized for this frequency, and their displacements are determined for a 20dB sidelobe level ratio. Two rectangular metal sheets are then symmetrically added as re∞ectors to focus the azimuth plane beam and increase the gain.