A Switchable Transmissive-Reflective Metasurface Unit for Full-Space Continuous Phase Modulation

Driven by the growing demand for electromagnetic wave modulations, programmable metasurfaces are expected to achieve wider spatial coverage and higher phase modulation accuracy. However, existing solutions cannot simultaneously satisfy the requirements of full-space propagation and continuous phase modulation. To address this issue, this letter proposes a metasurface unit topology based on a receiving-reradiating structure that enables continuous phase modulation in full space. Based on this topology, a switchable transmissive-reflective metasurface unit with continuous 360° phase modulation capability is designed. Simulations and measurements validate a phase modulation range of over 360° in both transmission and reflection modes.