Method and apparatus for reducing channel induced errors in speech signals

摘要

The invention proposes to improve the performance of the conventional methods of correcting channel transmission errors without increasing the redundance of encoding the channel. It is particularly advantageous for the systems which may be subjected to very poor transmission conditions such as radio interference or any other noise phenomenon in the channel. The invention provides the addition of a specific correction device after decoding the channel for detecting and correcting the residual channel errors exceeding the correction capacity of the channel decoder. It also proposes that the signal supplied by the decoder is a speech signal constituted by a limited number of determined speech elements. The invention provides permanent vocal recognition of the received signal with the aid of a dictionary of speech elements for detecting the transmission errors and for correcting them by replacing the erroneous part in the received signal by a synthesized part on the basis of the speech dictionary.