Low-Scattering Circularly Polarized Antenna Array with High Aperture Efficiency

A low-scattering circularly polarized antenna array with high aperture efficiency is proposed in this paper. The integrated antenna unit can realize circularly polarized radiation in X-band, and also acts as a polarization cancellation structure in the case of plane wave irradiation. The integrated and its mirror unit act as the artificial electromagnetic surface structure for polarization conversion. The mirrored design realizes the effect of monostatic RCS reduction based on polarization phase cancellation of reflected plane wave. The antenna units are formed into a 16-element array using sequential rotary feeding technique, which can achieve circularly polarized radiation characteristics in X-band, with 3-dB axial ratio bandwidth of 21.26% and the gain of 16.3 dBic at 10 GHz. The calculated aperture utilization factor is 74.63 %. Moreover, the antenna array has in-band and out-of-band low-scattering characteristics from 7 GHz to 15 GHz.