Switched Combination of Simplified Kalman Filter and Affine Projection Algorithm for Acoustic Feedback Cancellation

Acoustic coupling between the microphone and loudspeaker is a major issue in open-fit digital hearing aids. When compared to close-fit aid, an dramatically reduces signal quality limits potential maximum stable gain. Adaptive feedback cancellation (AFC) practical method for reducing influence of acoustic coupling. However, because high correlation incoming signal, it might induce bias calculating path if not carefully considered, especially when spectrally coloured, as speech music. For decreasing this bias, prediction error (PEM) well recognised. In paper we proposed switched PEM based hybrid combination simpliedkalman filter affine projection algorithms (H-SKF-APA), with soft-clipping that allows further increase convergence/tracking rates, resulting better ability recover from unstable or howling state. Simulation results showed algorithm performed better.