Quadratic-gradient metasurface-dome for wide-angle beam steering phased array with reduced gain-loss at broadside

Recently, the use of deflecting covering meta-domes for increasing the scanning range of a phased array has been proposed. Although promising, this solution still presents some inherent limitations, such as the significant reduction of the broadside gain compared to the original array, as well as the complexity of the implementation due to the need for a continuous phase profile. This work aims at proposing some technical solutions for maximizing the meta-dome performance and reducing the gain-loss at broadside. By properly discretizing and engineering the phase profile along the dome and by taking into account the different angles of incidence onto the meta-cells, we show how it is possible designing realistic meta-domes with reduced insertion loss at broadside, improved steering capabilities, and a reduced profile.