| 摘要 |
A parametric speech codec; such as a CELP, RELP, or VSELP codec; is integrated with an echo canceler to provide the functions of parametric speech encoding, decoding, and echo cancellation in a single unit. The echo canceler (90) includes a convolution processor (116) or transversal filter that is connected to receive the synthesized parametric components, or codebook basis functions, of respective send and receive signals being decoded and encoded by respective decoding and encoding processors (130, 94). The convolution processor (116) produces an estimated echo signal for subtraction from the send signal. In order to process the synthesized parametric components having distinct basis functions in the convolution processor, conversion means (142, 145) are provided for providing the receive-side parametric component to the processor, or for providing the estimated echo signal, in terms of the send-side parameter. Plural convolution processors are provided for processing respective parametric components of the desired coding scheme.
|
