Speaker
Description
Active impedance control offers a versatile framework for shaping wave propagation by dynamically adjusting generalized boundary conditions through feedback. Electroacoustic resonators are an attractive platform for this purpose, as their target acoustic impedance can be individually programmed through a pressure-based, current-driven control law. This reconfigurability makes them potential candidates for implementing spatially varying boundary conditions without mechanical modification. This work investigates the effect of spatially modulating the control law parameters of an electroacoustic resonator array on the reflected acoustic field. A periodic modulation is applied to the target stiffness along the metasurface, and the resulting scattered field is analyzed using a Bloch–Floquet expansion that predicts the wavenumbers of the generated spatial harmonics. Finite element simulations confirm that the modulation generates harmonics whose propagation angles are governed by the modulation wavenumber, enabling controlled beam splitting away from the specular direction. The results demonstrate programmable reflection control through active spatial modulation of the surface impedance, providing a path for the analysis and design of reconfigurable acoustic metasurfaces and active metaliners.