ESTIMATION OF DIGITAL LOW-RATE ENCODED VOICE LINK PERFORMANCE FROM INSTRUMENTAL MEASUREMENTS

The rapid introduction of low-rate digital voice coding technology in the telephone network has highlighted the need to develop inexpensive methods that can be used for the real-time telecommunication link tran smission performance characterization. In low-rate systems, such chara cterizations are typically undertaken by means of subjective assessmen ts. In this paper the correlation between subjective and instrumental assessments of low-rate digital voice coder transparency to voice and nonvoice signals is quantified. From this it will be seen that meaning ful information on link performance with voice signals can be obtained over a wide range of engineered link quality using instrumental techn ology employing nonvoice signals.