Adaptive multi-frequency feedforward active noise control systems

The performance of Filtered-X Least Mean Square (FXLMS) based active noise control (ANC) may degrade for multi-frequency noise sources. This paper proposes an alternative feedforward ANC system to address multi-frequency noises. We separate the multi-frequency noises into several band frequency noises by using finite impulse response (FIR) filters and then develop a new multi-channel ANC design method by means of FXLMS algorithm. Finally, the frequency estimation method is incorporated into the proposed ANC scheme to provide another improved ANC system. The error convergence and the system stability are proved and simulation results are given to show the efficacy of the proposed schemes.