Objective measures for real-time evaluation of adaptive feedback cancellation algorithms in hearing aids

This paper discusses objective measures for real-time evaluation of feedback cancellation algorithms in hearing aids in the presence of non-white input signals. Based on these measures, the maximum stable gain, the sound quality and the time required to recover from instability are determined for several real-time frequency-domain adaptive feedback cancellation algorithms, including adaptive feedback cancellation with bandlimited adaptation and prediction-error method based adaptive feedback cancellation (PemAFC) with autoregressive modelling of the desired signal. Of all the evaluated methods, the PemAFC with adaptive desired signal model achieves the best feedback suppression for a tonal music signal and the shortest time to recover from instability.