A Broadband Circularly Polarized Antenna with Low RCS

In this paper, a circularly polarized antenna with a low radar cross section (RCS) based on nonuniform metasurfaces is proposed. The metasurface is composed of four elements, which are arranged orthogonally in a 2x2 array. Each element is a nonuniform metasurface of 4 x 4 metallic patches. By feeding with a 90 degrees phase difference, the antenna achieves circular polarization radiation. For the radiation case, simulated results show that the proposed antenna possesses a -10 dB impedance bandwidth of 47.05%, 3 dB axial ratio of 42.35%. The peak gain of the antenna reached 12.74 dBic. For the scattering case, the RCS reduction under normal incidence is higher than 6 dB in the operating frequency band of the antenna.