Design of large mm-wave beam-scanning reflectarrays

Beam scanning reflectarrays represent an attractive alternative to MMIC-based phased array antennas, particularly at mm-wave frequencies, thanks to their potential low costs and high performance. In this paper, a simple but effective reconfigurable reflecting element is presented and the design procedure is described. An architecture for 2D electronic beam steering with reduced number of control signals, suitable for large reflectarray antennas, is presented. To demonstrate the feasibility of the proposed solution, a prototypal reflectarray antenna operating at 25 GHz has been designed and fabricated. Comparison with measured results shows very good agreement and confirms the capability to electronically steer the antenna beam.