A novel approach for single microphone active noise cancellation

This paper presents a novel approach for subband feedback active noise control (ANC). Wideband ANC systems often involve adaptive filters with hundreds of taps. Using subband processing can considerably reduce the length of the adaptive filter. Conventional subband algorithms are generally based in the frequency domain and use at least 2 sensors. This paper presents a time domain algorithm for single sensor subband feedback ANC using relatively short fixed FIR filters to do the subband processing. The adaptive coefficients in the system are updated using a weight constrained NLMS algorithm for feedback ANC. The proposed subband algorithm had a significant performance advantage over the traditional single band ANC algorithm in terms of the rate of convergence and the noise attenuation that could be obtained.