Integrated metasurface for efficient polarization conversion and high-gain, low-RCS EM radiation.

This paper presents an innovative design that combines the functionalities of a polarization convertor and an electromagnetic (EM) radiator into a single integrated metasurface. The metasurface consists of two identical metallic split-rings, a circular-shaped patch structure, a dielectric layer, and a reflective metallic ground. The polarization convertor component efficiently converts waves polarized in the x- or y-direction into cross-polarized waves within a frequency range of 8-13 GHz. It exhibits wideband resonances and achieves a high conversion efficiency. In the context of low-observable platforms, traditional high-gain antennas often suffer from a large radar cross section (RCS). To overcome this challenge, the same metasurface is utilized for EM radiation, enabling a high gain of 16.5 dBi while maintaining a low RCS. This is accomplished by strategically rotating the double-slotted metallic split-rings at 90 ∘, 180 ∘, and 270 ∘ in four distinct regions. Through this rotation, destructive interference cancellation occurs, resulting in wideband reduction of the RCS. Experimental results validate the effectiveness of the proposed metasurface in serving both applications, namely polarization conversion and EM radiation.