SPECTRAL SUBTRACTION NOISE SUPPRESSION METHOD

摘要

A spectral subtraction noise suppression method in a frame based digital communication system is described. Each frame includes a predetermined number N of audio samples, thereby giving each frame N degrees of freedom. The method is performed by a spectral subtraction (150) function ~(.omega.) which is based on an estimate (140) ~v(.omega.) of the power spectral density of background noise of non-speech frames and an estimate (130) ~x(.omega.) of the power spectral density of speech frames. Each speech frame is approximated (120) by a parametric model that reduces the number of degrees of freedom to less than N. The estimate ~x(.omega.) of the power spectral density of each speech frame is estimated (130) from the approximative parametric model.