Design of Tunable Broadband Graphene-Based Metasurface with Amplitude-Phase Modulation

Due to the growing scarcity of spectrum resources in the low-frequency band, the requirement of beam-reconfigurable antennas in the millimeter wave band is urgent. In this paper, a W-band graphene-based metasurface working in a broad bandwidth is proposed with reflective amplitude coding. Here, graphene sheets play a dual role in radiating and regulating electromagnetic waves. By adjusting the Fermi levels of graphene, the reflective amplitude and phase of the metasurface can be modulated simultaneously, enabling multi-beam switching and beam deflection in far-field. The proposed metasurface achieves amplitude-phase modulation within a significantly wide bandwidth which covers 75-91.5 GHz and 99.3-115 GHz. By optimizing the coding patterns, the proposed graphene-based metasurfaces are able to not only realize 2-D beam steering, but also achieve beam switching from single beam to four beams at 87 GHz. The proposed design provides a novel solution for the flexible manipulation of millimeter waves, which can be applied to various fields such as vehicle radar, satellite communication, 6G wireless communication, and beyond.

Automated summary

Due to the scarcity of spectrum resources in the low-frequency band, there is an urgent need for beam-reconfigurable antennas in the millimeter wave band. This paper proposes a W-band graphene-based metasurface with reflective amplitude coding, which can modulate the reflective amplitude and phase through adjusting the Fermi levels of graphene. The metasurface achieves amplitude-phase modulation in a significantly wide bandwidth and allows for multi-beam switching and beam deflection in far-field.