Fig. 4: Ideal simulation scattering patterns at multiple frequencies generated by ASTCM when all partitions are modulated simultaneously.

a–c The metasurface is divided into four partitions with the modulation frequencies ∆f₁ = 100 kHz, ∆f₂ = 200 kHz, ∆f₃ = 300 kHz, and ∆f₄ = 400 kHz. d–f The metasurface is divided into eight partitions with the modulation frequencies ∆f₁ = 100 kHz, ∆f₂ = 200 kHz, ∆f₃ = 300 kHz, ∆f₄ = 400 kHz, ∆f₅ = 500 kHz, ∆f₆ = 600 kHz, ∆f₇ = 700 kHz, and ∆f₈ = 800 kHz. The main lobes of the four-partition case and eight-partition case are directed at different angles. a \({f}_{1} \sim {f}_{4}\): −60°, −30°, 0°, 50°; b \({f}_{1} \sim {f}_{4}\): −60°, −30°, 17°, 50°; c \({f}_{1} \sim {f}_{4}\): −44°, −30°, 0°, 50°. d \({f}_{1} \sim {f}_{8}\): −60°, −50°, −30°, −10°, 0°, 20°, 40°, 60°; e \({f}_{1} \sim {f}_{8}\): −60°, −50°, −30°, −10°, 7°, 20°, 40°, 60°; f \({f}_{1} \sim {f}_{8}\): −65°, −50°, −30°, −10°, 0°, 20°, 40°, 60°.