Space‐Frequency Metasurface for Frequency and Function Multiplexing

ABSTRACT Electromagnetic (EM) metasurfaces offer powerful capabilities to manipulate wave properties across multiple dimensions, including amplitude, phase, and polarization. However, achieving efficient multi‐frequency multiplexing remains a significant challenge due to system complexity and costs. For instance, while space‐time metasurfaces facilitate frequency‐domain control through time‐domain modulation, they often suffer from prohibitive power consumption, complex control circuitry, and substantial hardware overhead. Here, inspired by the modular assembly of interlocking building blocks, we propose a space‐frequency metasurface paradigm for frequency multiplexing. By introducing spatial sparsity and geometric periodicity as novel degrees of freedom, low‐complexity and cost‐effective multi‐frequency multiplexing can be achieved. Our investigation reveals that the EM performance of the metasurface exhibits robustness against array thinning, thereby liberating spatial capacity to interleave heterogeneous meta‐atoms with distinct periodicities. Governed by their distinct spatial periodicities, these dimensionally scaled meta‐atoms are engineered to independently regulate multiple frequency bands with low inter‐frequency crosstalk. To demonstrate the versatility of this platform, we implement an integrated sensing and communication platform, achieving simultaneous wireless data transmission and non‐contact vital sign monitoring. It provides a template for the development of multifunctional EM materials and establishes a robust conceptual foundation for the cross‐disciplinary fusion of materials science and modern information technologies.