The speech of the Voice over Internet Protocol (VoIP) system is degraded by network layer problems which include delay, packet loss and jitter. The implementation of signal through digital signal processor can improve the quality of degraded VoIP signal. The work in this paper presents the comparison of speech quality for narrowband and wideband VoIP using TMS320C6713 DSP processor. The VoIP simulations are conducted for G.729A and AMR-WB speech coders at different packet loss rates. The digital filtering algorithm is implemented on degraded VoIP speech signal. The results of implementation experiment indicate much improvement in signal quality with wideband coders. The results are validated through the measurement of enhancement signal using perceptual evaluation of speech quality (PESQ) measurement.

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Narrowband VoIP Wideband VoIP Signal Processing TMS320C6713 DSP Processor