Voice coding process and device for implementing said process

Abstract From the Canadian patent

The voice signal is analyzed to derive therefrom a low frequency base band signal, linear prediction coefficients and HF descriptors. Said HF descriptors include HF energy indications as well as indications relative to the phase shift between the low frequency and the high frequency band. Said HF descriptors are used during the voice synthesis operation to provide an inphase HF bandwidth component to be added to the base band prior to be used for driving a linear prediction synthesis filter tuned using said linear prediction parameters. Fig. 2, FR 9 85 008