Adaptive Noise Canceller with Snr Estimate Switchover for Stepsize Control

Abstract

This paper proposes an adaptive noise canceller with SNR estimate switchover for stepsize control. The SNR estimate is switched from a first estimate to a second one when the latter takes a smaller value than the former. The first estimate is a power ratio of the primary and the reference input signals, which is newly introduced to enable initial coefficient adaptation. The second estimate is a power ratio of the error signal and the adaptive filter output, which is used in a conventional stepsize control. Switchover from the first estimate to the second guarantees initial coefficient adaptation by the former and provides accurate SNR estimation by the latter. Evaluations with speech-speech inputs and speech-noise inputs demonstrate that use of the second SNR followed by the first SNR successfully makes the coefficient vector norm approach the true value which represents convergence.