US Patent 7205948 Variable inclination array antenna

An antenna array includes an upper conductive plate structure comprising a lattice array of holes to form a radiating aperture. A lower conductive plate structure is disposed in a spaced relationship relative to the upper plate structure. The lower plate structure has an upper surface whose spacing from a lower surface of the upper plate varies in a first direction parallel to the lower surface. The array includes relative rotation apparatus for imparting relative rotational movement between the upper plate structure and the lower plate structure.