A 2-Bit Low-Profile Reconfigurable Ka-Band Transmitarray Fed by a 2×2 Conformal Array

A low-profile reconfigurable transmitarray (TA) architecture is proposed in this paper for Ka-band applications. The antenna system is based on a 24×24-element flat-lens illuminated by an array of 2×2 conformal horns. Considering the proposed focal system, a focal distance (F) of 30 mm, corresponding to an F/D equal to 0.25, has been selected as an acceptable trade-off between aperture taper efficiency and thickness. This corresponds to a 58% profile reduction if compared to the classical transmitarray illuminated by a standard 10-dBi horn (F = 70 mm).