VOICE SIGNAL PROCESSING SYSTEM MOUNTED WITH ECHO CANCELLER AND VOICE SIGNAL PROCESSING METHOD

In order to prevent generation of a trapezoidal signal waveform due to limitations on dynamic ranges in an echo canceller and an echo path as voice signal transmission paths, a voice signal processing circuit of the voice signal processing system processes a waveform such that its signal level falls within the narrowest dynamic range without causing an overshoot and waveform crack. Process of a signal waveform is selectively conducted only of a waveform of a voice signal whose signal level is high to be liable to have distortion. As to a voice signal whose signal level is low and originally within a dynamic range, the signal is transmitted without having its waveform processed.