Enhancing the Beam Scanning Capability of Phased Arrays Using Quadratic-Gradient Metasurface Dome

In this contribution, we propose a quadratic-gradient metasurface dome operating in the near-field region of a dual-polarized phased array able enhancing its grating-lobe-free scanning range without affecting its other characteristics. The dome consists of an array of Huygens unit-cells exhibiting an extremely low insertion loss and a proper phase shift in transmission. The main characteristic of the proposed dome is the quadratic-gradient phase profile, which minimizes the beam divergence in broadside direction, whereas linearly increases the scanning region in off-broadside pointing angles. A proper set of numerical simulations have been performed showing the capability of the proposed dome to enhance the grating lobe free scanning region from −58° to −83°.