Beam-Steerable Reflectarray Antenna for C-Band Radar

An electronically beam-steerable reflectarray antenna for surveillance radar is presented in this paper. The tunable unit cell of the reflectarray is designed based on a single-layer substrate integrated with a varactor. The reflection phase of the unit cell has been confirmed to provide a good phase range of 330.6°. As an example, a 12 × 12 element reflectarray antenna is envisaged and simulated at C-band. Profit from the wide tuning phase range of each element, a broad scanning range of up to ±60° over the whole band is achieved. The simulated results show that the side lobe level of the bi-static radar reflection cross section (RCS) is below -10 dB in the range of ± 55°.