Deflecting superstrate solutions for wide-scanning array

Design considerations on a wide-scanning array antenna for on-craft satellite communications are presented in this paper. For this type of application, a scanning coverage of 80° over a 15% fractional bandwidth in Ka-band is required. A solution based on a passive superstrate illuminated by a phased array is recognized as the most encouraging. Two kinds of structures are investigated: a flat solution and a flattened dome. The dome is represented as a surface with an optimized phase shift distribution in order to obtain high performances up to the extreme scan angles. A good gain profile is achieved in both cases.