An adaptive feedback active noise control system

Measurement noise is an unavoidable problem in measurements on physical systems. This paper presents an analysis of the effect of measurement noise on the performance and stability of the adaptive feedback active noise control (ANC) system. A solution is also proposed to alleviate the effect of measurement noise on feedback ANC systems. In adaptive feedback ANC systems, the multi-tonal noise used as reference signal is synthesized from the residual error signal, which is generally corrupted with measurement noise. The proposed algorithm estimates the frequencies of the multi-tonal noise and generates an enhanced version of it. This enhanced signal is used as reference signal in the feedforward ANC configuration. An analysis of the effect of the accuracy of frequency estimation on the performance of ANC is presented. Simulation results to verify the efficacy of the proposed algorithm are also presented.