An Ultra-Wideband Circular Polarization-Maintaining Metasurface and Its Application in RCS Reduction

In this work, a circular polarized (CP) maintaining metasurface is proposed, which can realize ultra-wideband CP-maintaining reflection and make its co-polarization reflection coefficient under CP incidence close to 1.0 in the frequency band 6.2-26.4GHz; in addition, by rotating its unit cell structure, Pancharatnam-Berry (PB) phase can be generated in its co-polarized reflection coefficient under CP incidence. Thus based on the CP-maintaining metasurface, a 2-bit PB coding metasurface is further proposed for Radar Cross Section (RCS) reduction. The simulated results show that the proposed PB coding metasurface has excellent performance in RCS reduction, compared with a pure metal plate with the same size, its RCS can be reduced more than10dB under arbitrary polarization incidences in the frequency band 6.2-26.5GHz with relative band of 124.1%. Finally, an effective experimental validation is carried out.