基于2-bit可重构太赫兹编码超表面的RCS缩减设计OA

Coding metasurfaces can flexibly manipulate electromagnetic waves,providing high degrees of freedom for employing coding sequences to control electromagnetic waves in the frequency domain.This paper adopts Dirac Semimetal(DSM)to design a three-layer reflective unit cell.Without altering the unit cell structure,the Fermi level(EF)of DSM is tuned by applying an external bias voltage,thereby achieving 2-bit coding at 1.90 THz with phase stability of±60°.To address electromagnetic waves under different incident angles,the far-field scattering theory is utilized,and the genetic algorithm is employed to specifically optimize the metasurface array.Taking incident elevation angles of 0°,15°,30°,45°,and 60° as examples,five arrays are designed,and the coding metasurface is modeled and analyzed.The results demonstrate that when electromagnetic waves are incident perpendicularly,Radar Cross Section(RCS)reduction exceeding 10 dB is achieved within the range of 1.77～2.47 THz,with a maximum value of 28.4 dB.When electromagnetic waves are incident at an elevation angle of 60°,RCS reduction exceeding 10 dB is realized within the range of 1.82～2.24 THz,reaching a maximum of 15.2 dB,thereby achieving broadband wide-angle RCS reduction.