Adaptive Rate Control for VoIP in Wireless Ad Hoc Networks

The purpose of this paper is to study the performance of voice transportation in wireless ad hoc networks. First we analyze the characteristics of wireless channel and speech coding standard AMR-WB, and then we propose an adaptive source network rate control scheme to battle packet loss. The basic idea is to adapt the voice coding bit rate to the available network bandwidth in order to maximize the quality of voice. The PESQ MOS value is used as the evaluation criteria for the adaptive rate control scheme. Moreover, the discontinuous transmission operation and packet combination are utilized to improve the performance further. The experimental results show the effectiveness of this scheme.

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