Figure 1.

Conceptual illustration of ASTCM. The reflection phase of the meta‐atoms can be dynamically controlled by changing the biasing voltages of the varactor diodes. Coding strategies are displayed in the left‐bottom corner, in which each block represents a coding state. The color of each block represents the periodic reflection phase, and height of each block represents the duration time for one period. The reflection power spectrum is shown at the bottom. In the illustrated example, the time‐coding sequences adopted to the spatial meta‐atoms are similar, whereas the periods are different. When the reflection phase increases linearly and continuously from 0 to 2π in different periods, the scattered wave can automatically scan the space with time.