基于时延预测的VoIP抖动缓冲控制算法

Jitter buffer control algorithm of VoIP using time-delay prediction

网络时延抖动是影响VoIP语音质量的重要因素之一.为消除时延抖动,提高VoIP语音质量,提出一种基于时延预测的自适应抖动缓冲控制算法.算法采用AR模型为时延序列建模,通过LMS算法进行时延的一步预测,并根据时延预测值,以缓冲时延最小化为目标,自适应调节缓冲区大小.仿真试验结果表明,该算法在网络平稳时,取得了较小的缓冲时延,在网络状况突发时,具有较快的收敛速度,可以有效提高VoIP语音质量.

Network time-delay jitter is one of the premier factors of influence on the quality of voice in VolP. In order to eliminate the jitter solve this issue and achieve better voice quality in VolP, an adaptive jitter buffer control algorithm is proposed on the basis of time-delay prediction. The AR model is adopted in this algorithm to establish a model of time-delay series and one-step prediction of time delay is achieved by using LMS algorithm. Then the jitter buffer size is adaptively adjusted based on the predicted data to a- chieve the minimum Of buffer-delay. Simulation results show that this algorithm will make the buffer de- layless when network is stable and will have also a faster convergence speed when network condition chan- ges abruptly, so that the voice quality in VolP can be improved effectively.