Performance Evaluation of EVRC-Encoded Voice Traffic over CDMA EVDO Rev. A

Abstract

Although CDMA EVDO Rev. A provides significant improvements over EVDO Release 0 that make it well suited for VoIP-like applications [3], it remains unclear about its performance in terms of quantitative evaluations with different real implementation scenarios. To understand the system design tradeoffs, we first investigate the traffic characteristics of EVRC-encoded real voice traces and we find that the correlation structure of voice traffic exhibits strong long-range dependency. We further observe that the burst length distribution of voice traffic is heavy tailed. In the major part of our study, we examine the tradeoff between the initial playout delay and the voice quality for real voice traces over CDMA EVDO Rev. A. We also examine the tradeoff between voice quality and different RF conditions. Additionally, we address the performance aspects of voice traffic over CDMA EVDO Rev. A with adaptive frame bundling (AFB) techniques and the impact of different treatments of the eighth rate frames for EVRC-encoded voice traffic. Finally, we examine the impact of hard handoff and random frame errors on voice quality for EVRC-encoded voice traffic over CDMA EVDO Rev. A.