Chessboard Mushroom-Type Metasurface for Beamforming Applications

TL;DR

This paper presents a reconfigurable microwave metasurface with a chessboard pattern that can dynamically steer beams by adjusting external voltages, demonstrated through analytical, numerical, and experimental methods.

Contribution

The study introduces a novel chessboard-like metasurface with nonlinear capacitive loads for beam steering, showing effective reconfigurability with a small array size.

Findings

Beam direction can be controlled by external voltages.

A small 3-by-10 element array effectively redirects beams.

The metasurface's behavior is validated analytically, numerically, and experimentally.

Abstract

A reconfigurable microwave reflectarray metasurface (MS) is investigated for beamforming applications. The reflected beam direction is changed by applying external dc voltages, which create a reflection phase gradient on the structure. The studied MS comprises a chessboard-like array of metallic patches placed over a grounded dielectric slab with metallic vias connecting the patches to the controlling lines. Tunability is achieved with nonlinear capacitive loads (varactors) inserted between the corners of the metallic patches. The MS is studied analytically, numerically and experimentally, from which reshaping of the radiation pattern is observed according to the applied control voltages on the MS elements. It is shown that the proposed MS-based reflectarray with just 3-by-10 elements is already sufficient to redirect the beam in different directions.