Hyperuniform Radiation-Scattering Meta-Device for Scattering Suppression at Grazing Incidence

Abstract

Low-scattering periodic antenna arrays have been fully investigated in terms of their scattering properties under normal incidence. However, strong scattering can also occur due to diffraction peaks generated by periodic structures under grazing incidence. In this letter, we present a hyperuniform radiation-scattering meta-device (HRSMD) that effectively maintains in-band radiation while reducing out-of-band scattering at grazing incidence. The proposed unit consists of a U-shaped antenna and a 5 × 5 meta-atom array loaded with 100 Ω resistors. A hyperuniform distribution is introduced to arrange all units, effectively suppressing diffraction peaks caused by a periodic array under grazing incidence. The proposed HRSMD behaves like a periodic array while resembling a random array with a disordered spatial configuration. The fabricated sample shows a maximum measured gain of 16 dBi at 3 GHz, maintaining comparable radiation performance to a periodic array with the same aperture size. Additionally, we have fabricated a low-scattering carrier to investigate the scattering performance of the HRSMD at grazing incidence. Compared to the periodic array, the HRSMD effectively reduces the radar cross section (RCS) by an average of 6 dB (horizontal polarization) and 8 dB (vertical polarization) under grazing incidence from 8 GHz to 12 GHz. At specific frequencies, the maximum RCS reduction reaches 26 dB and 31 dB for horizontal and vertical polarizations, respectively. The proposed HRSMD has significant potential for stealth applications involving periodic/nonperiodic arrays at grazing incidence.