  Adaptive algorithm based on multi-channel linear prediction is an effective
dereverberation method balancing well between the attenuation of the long-term
reverberation and the dereverberated speech quality. However, the abrupt change
of the speech source position, usually caused by the shift of the speakers,
forms an obstacle to the adaptive algorithm and makes it difficult to guarantee
both the fast convergence speed and the optimal steady-state behavior. In this
paper, the RLS-based adaptive multi-channel linear prediction method is
investigated and a time-varying forgetting factor based on the relative
weighted change of the adaptive filter coefficients is proposed to effectively
tracing the abrupt change of the target speaker position. The advantages of the
proposed scheme are demonstrated in the simulations and experiments.
