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In recent decades, metasurfaces have attracted considerable interest to generate vortex beams, that is, orbital angular momentum (OAM) carrying beams. However, the existing OAM metasurfaces are mostly fixed‐mode or with single function. Here a concept of multifunctional vortex beam generation is proposed, and is realized by a dynamic reflective metasurface which is capable of controlling the vortex beam spatiotemporally. The proposed metasurface has the ability to control OAM mode and to observe rotational Doppler effect. As proof of concept, it is presented that the proposed metasurface can generate an l = −1 or l = +1 OAM mode reconfigurable beam, and an l = +1 spinning OAM beam with rotational Doppler effect. Both simulated and measured results show the effectiveness of the proposed multifunctional OAM metasurface which has two different functionalities. The proposed multifunctional OAM metasurface may have potential applications in OAM multiplexing communications and harmonics manipulation by rotational Doppler effect. [ABSTRACT FROM AUTHOR]

Programmable metasurface, or reconfigurable intelligent surface is one of the most promising strategies to enhance communication and sensing capacities via arrays of reconfigurable meta‐atoms. The functionalities of conventional programmable metasurfaces are usually limited, and active meta‐atoms are connected with steering‐logic board through cables, which makes the whole system inconvenient for installation and stable use. Here an all‐in‐one integrated multifunctional metasurface for various application purpose is proposed. The integration of metasurface and steering‐logic board produces an all‐in‐one system, which makes it compact, low profile, and stable. The novel meta‐atom structure provides all‐in‐one functionalities, including 1) dispersion‐reconfigurable spatial phaser for analogue signal processing, 2) polarization conversion, 3) beam steering and orbital angular momentum generation for high‐speed communication and, 4) near‐field scanning for sensing. The proposed metasurface also has a broadband property, which is operating from 9.5 to 10.5 GHz with 10% relative bandwidth. Such a design integrates functionalities of signal processing, communication, and sensing in a single programmable metasurface, which makes it especially useful for integrated sensing and communication toward next‐generation wireless networks. [ABSTRACT FROM AUTHOR]