Fig. 1. Coding metasurface. (a) Schematic diagram of unit structure; (b) VO₂ phase change process and generated full-space multi-frequency multi-beam

Fig. 2. Transmission amplitude and phase of coding metasurface unit. (a) LCP; (b) RCP

Fig. 3. 1-bit anisotropic reflective coding metasurface units with dual frequency points. (a) 0 (f₂-l_x1) and 1 (f₂-l_x2); (b) 0 (f₂-l_y1) and 1 (f₂-l_y2); (c) 0 (f₃-l_m1) and 1 (f₃-l_m2); (d) 0 (f₃-l_n1) and 1 (f₃-l_n2)

Fig. 4. Coding metasurface. (a) Overall and partial diagrams; coding sequences (b) A, (c) B, (d) C, (e) D, and (f) E

Fig. 5. Transmitted vortex wave. (a) Far-field scattering; (b) phase

Fig. 6. Two symmetrical beams. (a) Far-field scattering and (b) electric field at f₂=0.5 THz; (c) far-field scattering and (d) electric field at f₃=0.85 THz

Fig. 7. Four symmetrical beams. (a) Far-field scattering; (b) 2D electric field distribution

Fig. 8. Coding metasurface. (a) Scattered field distribution; (b) comparison of RCS shrinkage with metal plate