A sectoral horn is a rectangular waveguide horn that flares in a single plane
Structure: The rectangular waveguide flares only along the E-plane (narrow side), while the H-plane (broad side) stays unchanged.
Aperture: Tall and narrow with a large E-plane aperture and a small H-plane aperture.
Structure: The rectangular waveguide flares only along the H-plane (broad side), while the E-plane (narrow side) stays unchanged.
Aperture: Wide and short with a large H-plane aperture and a small E-plane aperture.