Noise suppression via controlled ion acoustic wave propagation

Current active and passive noise reduction methods heavily rely on factors such as material properties, structural design, and weight, with noise cancellation processes primarily focused on gaseous, liquid, and solid states. In this study, we propose a novel theoretical model for modulating incident noise using ionic acoustic waves generated by corona discharge in the plasma state. These ionic acoustic waves are produced through the combined effects of thermal pressure from plasma ions and electrostatic forces arising from charge separation. Plasma-acoustic wave modulation based on negative corona discharge alters the dielectric field within the ionization region by influencing the motion of charged ions and electrons, thereby affecting the acoustic wave propagation process. Specifically, the generated ionic acoustic waves interfere with incident noise waves, leading to noise reduction. By adjusting the applied voltage, electrode gap, and discharge position in a needle-plate discharge configuration, the frequency, phase, and amplitude of the ionic acoustic waves can be precisely controlled, thereby modifying the interference outcomes. Theoretical verification demonstrates that tailored ionic acoustic waves effectively cancel incident noise within the 1–1000 Hz and 1000–2000 Hz frequency ranges. This work confirms the robustness of plasma-based corona discharge for future acoustic wave modulation applications and provides a theoretical foundation for developing “plasma-state noise reduction” acoustic functional devices.