Active noise control algorithm with saturated actuator

Abstract

Active noise control system has received its attention in various technical field such as headphone, motor vehicle, and etc. Many of the active noise control algorithm, filtered-x lms algorithm representatively, were based on the linear system. However, the real system exhibits nonlinear characteristics behavior like saturation in the transducers, amplifiers, A/D, D/A converters, and actuators. Among these nonlinear effects, this paper will concentrate on the saturation effects on the actuator. Saturation on actuator may cause clipping effect on the control signal which may distort the signal in consequences. Also, with the linear algorithm, the control filter may diverge due to the saturation. Therefore, this paper suggests the weight filter scaling algorithm for the actuator saturation. By scaling the weight filter, it prevents the control signal distortion and weight filter divergence, with better noise reduction performance compared to the conventional linear active noise control algorithm.