Evaluation of a hybrid active noise control system with acoustic feedback

This paper presents a hybrid active noise cancelling (HANC) algorithm with online secondary path estimation, together with its evaluation under acoustic feedback distortion present in most feedforward ANC system. The HANC system provides a suitable solution to two important problems present in most ANC systems. The acoustic feedback is reduced using two FIR adaptive filters with feedforward and feedback configurations, respectively; together with the online secondary path modeling. Computer simulation results show that the HANC structure provides a good acoustic feedback cancellation, while the secondary path estimation method performs fairly well, providing better cancelation performance than other previously proposed structures.