| 摘要 |
A telecommunications network service (figure 1) overcomes the annoying effects of transmitted noise by a signal processing which filters out the noise using interactive estimations of a linear predictive coding speech model. The speech model filter uses an accurate updated estimate of the current noise power spectral density, based upon incoming signal frame samples which are determined by a voice activity detector (25) to be noise-only frames. A novel method of calculating the incoming signal using the linear predictive coding model provides for making intraframe iterations of the present frame based upon a selected number of recent past frames and up to two future frames (figure 3 and figure 10). The processing is effective notwithstanding that the noise signal is not ascertainable from its source.
|
