Design of reflective surface for cross-polarization conversion and RCS reduction

This paper presents the design of novel surface that can convert the incident EM-waves into its cross-polarized (orthogonal) component at millimeter wave frequencies. The unit cell composing the surface has a cut of wire along the diagonal with two closed rings above and below. The unit cell has three resonance frequencies at 84.32GHz, 85.6GHz, and 87.38GHz at which the polarization conversion reaches 100%. The results show a strong cross-polarization conversion from about 84.2GHz to 87.9GHz with polarization conversion efficiency of more than 83%. Moreover, if the surface is designed using the proposed unit cell and its mirrored one, the reflected EM-wave can be controlled freely and Monostatic RCS reduction can be achieved with diffuse reflection like backscattered RCS field pattern.