Design of a Scan Angle Enhancing RIS Antenna for High Frequency Short-Range-Radar Detection

In this work, we designed a scan angle-enhancing transmitted reconfigurable intelligent metasurface (RIS) antenna, which is closely illuminated by a non-standard passive array. Compared to the RIS space-fed by a remoted horn source, the beam scan range can be enhanced from ±60°×±60° to ±70°×±70° with stable scan losses of no more than 3 dB. Meanwhile, its focal ratio and profile can be reduced. This solution can be potentially used to realize large-scan-range and low-profile short-range radars, satisfying the wide-range detection and communication requirements of automotive and satellite applications.