An all-frequency-domain adaptive filter with PEM-based decorrelation for acoustic feedback control

A new method for acoustic feedback control is derived, combining an adaptive filter with a decorrelation strategy based on the prediction-error method (PEM) entirely in the frequency domain. This all-frequency-domain method extends existing methods combining a frequency-domain adaptive filter (FDAF) and time-domain PEM-based decorrelation. Such a combined approach is critical, since a standard adaptive feedback cancellation (AFC) procedure without proper decorrelation yields biased estimation results and hence does not provide suitable acoustic feedback control. The proposed modification allows to lower the computational complexity of the algorithm, while maintaining comparable performance.