Shared Aperture Metasurface for Bi-Functions: Radiation and Low Backward Scattering Performance

In this paper, a novel method to design a multifunctional metasurface (MS) is proposed and demonstrated. Inspired by shared aperture technology, the proposed MS is integrated with both radiation and low backward scattering performance. Each MS unit cell consists of two parts, polarization conversion surface part and radiation part. Different from traditional MS design, the proposed two parts are integrated together, and thus, bi-functions are realized in one surface. To acquire radiation performance, the feeding structure is added to each radiation in part by introducing an antenna design concept. The peak gain of the MS attains 18.1 dBi and main-beam patterns are all along the normal direction. To obtain low backward scattering performance, the polarization of an incident electromagnetic wave is transformed by the reflected MS. The reflected wave will have a 180 degrees phase difference through rotating the polarization conversion surface structure. Thus, two different types of MS units are arranged in chessboard array to achieve reflection suppression. The radar cross section reduction band is from 3.0 to 4.3 GHz with peak values of 7.2 and 16.8 dB. Both the simulated and experimental results prove that our method offers a feasible strategy for the multifunctional MS design which can lead to many exciting applications in different frequency domains.