Robust Wiener controller design with acoustic feedback for active noise control systems

Although the acoustic feedback could be alleviated by the neutralization method with a feedback model, an active noise control system could still suffer from being unstable if the feedback path exhibits significant variations. In this letter, a modified Wiener controller is introduced to enhance the robust stability with a fixed feedback neutralization filter. The proposed controller is designed with frequency-weighted penalties, which are adjusted iteratively according to Nyquist stability criterion. Experiment results based on a ventilation duct system shows that the robust stability could be achieved with the proposed method while a relatively good performance could be maintained.