Millimeter-Wave Prephased 1-bit Reconfigurable Metasurface for Circularly Polarized Single-Beam Steering

A millimeter-wave (mmW) pre-phased 1-bit transmissive reconfigurable metasurface is proposed for dynamic single-beam steering under circularly polarized plane wave incidence. The metasurface element is designed using a receiver-transmitter architecture, incorporating the concept of geometric phase to achieve continuous pre-phase encoding. The designed metasurface consists of 16 × 16 elements, each operating within the frequency band ranging from 27.2 to 28.6 GHz, which covers the n261 band for 6G mmW wireless communication. To suppress the unwanted mirror beams inherent to a 1-bit metasurface under plane wave illumination, a pre-phase distribution is utilized to break the central symmetry of the beam scattering pattern of the 1-bit metasurface. The performances of dynamic single-beam steering are evaluated through both theoretical analysis and full-wave simulation, which are then validated by the experiment of a fabricated metasurface prototype. The proposed methodology and metasurface could enhance the space utilization and communication capacity of 1-bit metasurfaces, potentially advancing their application in wireless communication systems.