为了减小阵列天线的雷达散射截面(RCS),设计并分析了基于石墨烯的可调谐极化转换超表面(PCM)。超表面包括周期性的梭形金属片,方形图案的石墨烯,和倾斜的光栅图案石墨烯。通过调整上(μ1)和下(μ2)石墨烯层的费米能级,实现了不同的国家。在状态1中,μ1=0eV,μ2=0.5eV,在1.65-2.19THz和2.29-2.45THz的带宽中,极化转换比(PCR)超过0.9。在状态2中,μ1=μ2=0.5eV,在1.23-1.85THz和2.24-2.60THz条带中,PCR大于0.9。在状态3中,μ1=μ2=1eV,在2.56-2.75THz和3.73-4.05THz条带中,PCR超过0.9。通过将PCM与阵列天线集成,在不影响天线的基本辐射功能的情况下,获得了可调谐的RCS降低。在状态1中,在1.60-2.43THz和3.63-3.72THz频率范围内,RCS降低大于10dB。在状态2中,在2.07-2.53THz中,RCS降低超过10dB,2.78-2.98THz,和3.70-3.81THz频段。在状态3中,在1.32-1.43THz中,RCS降低大于10dB,2.51-2.76THz,和3.76-4.13THz频率范围。这种极化转换超表面显示了可切换和可调谐天线RCS降低应用的巨大潜力。
A graphene-based
tunable polarization conversion metasurface (PCM) was designed and analyzed for the purpose of reducing the radar cross-section (RCS) of array antennas. The metasurface comprises periodic shuttle-shaped metal patches, square-patterned graphene, and inclined grating-patterned graphene. By adjusting the Fermi energy levels of the upper (μ1) and lower (μ2) graphene layers, different states were achieved. In State 1, with μ1 = 0 eV and μ2 = 0.5 eV, the polarization conversion ratio (PCR) exceeded 0.9 in the bandwidths of 1.65-2.19 THz and 2.29-2.45 THz. In State 2, with μ1 = μ2 = 0.5 eV, the PCR was greater than 0.9 in the 1.23-1.85 THz and 2.24-2.60 THz bands. In State 3, with μ1 = μ2 = 1 eV, the PCR exceeded 0.9 in the 2.56-2.75 THz and 3.73-4.05 THz bands. By integrating the PCM with the array antenna,
tunable RCS reduction was obtained without affecting the basic radiation functionality of the antenna. In State 1, RCS reduction was greater than 10 dB in the 1.60-2.43 THz and 3.63-3.72 THz frequency ranges. In State 2, the RCS reduction exceeded 10 dB in the 2.07-2.53 THz, 2.78-2.98 THz, and 3.70-3.81 THz bands. In State 3, RCS reduction was greater than 10 dB in the 1.32-1.43 THz, 2.51-2.76 THz, and 3.76-4.13 THz frequency ranges. This polarization conversion metasurface shows significant potential for applications in switchable and
tunable antenna RCS reduction.