Conformal Transmitarray for Scan Loss Mitigation with Thinned Reconfiguration

A conformal transmitarray with thinned control is presented, operating at 28 GHz. Its side panels are rotated to align with the maximum steering angle, increasing the gain and reducing the scan loss. The transmitarray is fed by an 8-element linear phased array antenna. Beam focusing to +/-53 degrees is demonstrated for two different directions, using combinations of crossed-slot unit cells. A unit cell placement rule is proposed to significantly reduce (i.e. thin) the required number of reconfigurable unit cells. A filling factor of 43% was achieved compared to a fully populated design. This reduces the cost and biasing complexity. By minimising scan loss, this antenna could improve the performance of 5G small-cell access points.