Agile design of cross-section enhancement of a conducting plate radar through active metasurface

The design concept of employing the dynamically reconfigurable scattering pattern to enhance radar cross-section is proposed and examined. In combination with varactor loading, a physical unit cell geometry with an embedded bias network for the varactors is utilized to build the metasurface. Biased by an applied direct-current source with voltage gradient, the proposed active metasurface can exhibit electrically tunable reflection phase distributions for either normal or oblique incidence plane wave, so as to achieve flexible redirection of the angle of reflection. As a result, the agile effect for monostatic or bistatic cross-section enhancement is then facilitated. Taking a conducting plate as an example, three different incidence and reflection scenarios are considered for calculation and full-wave simulation. Reconfigurable scattering patterns produced at the operating frequency of 10 GHz by the presented design are observed, which indicates its capability of real-time control of the angle of reflection. In conjunction with an experimental measurement, the effective enhancement of monostatic and bistatic cross-sections are validated.