Wideband and Polarization-Independent Radar Cross Section Reduction Using Holographic Metasurface

A strategy adopted for reducing radar cross section (RCS) of antenna by utilizing the holographic metasurface (HM), with preserving the radiation performance simultaneously, is proposed and discussed. The scheme is based on implementation of the HM capable of operation over a wide frequency band for both x- and y-polarized incident waves. By converting propagating waves into surface waves, which is achieved by the HM, the backscattering of the antenna is reduced. To demonstrate the proposed solution, a 2 ×2 slot array antenna, which is considered as a test case, is designed and fabricated. By placing the HM atop of the radiation ground of the slot array antenna, radar cross section reduction (RCSR) is dramatically accomplished over a frequency band ranging from 5 to 25 GHz. It is worth mentioning that the obtained RCSR at 14 GHz is as much as 20 dB. Taking the remarkable RCSR and acceptable effect on radiation characteristics into account, the proposed method can be a candidate for designing the low-RCS antennas.