G.729B中话音激活检测算法的改进及仿真  

Simulation and Improvement of VAD in G.729B

作　　者：胡斌[1] 黄冰[1] 罗保钦[1] 王苗[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,广西桂林541004

出　　处：《计算机系统应用》2010年第6期191-194,共4页Computer Systems & Applications

基　　金：广西自然科学基金(桂科自0640167)

摘　　要：VoIP中G.729B的话音激活检测算法(VAD)通常只是在高信噪比下才会有着良好的检测效果,而在低信噪比下或者有背景噪声的情况下检测效果却不佳。为此详细研究了自适应多速率语音编码(AMR)中的VAD2算法以及将其引入到G.729B中的可行性,并在此基础上对VAD2做了一些优化处理。通过Matlab仿真,发现优化后的VAD2无论是在高信噪比下还是在低信噪比下都有着相对良好的判决效果,同时也大大缩短了检测时间。实验结果表明:优化后的VAD2可用于G.729B算法中。The Voice Activity Detector（VAD） of G.729B in VolP can only work well in the high SNR, while in the low SNR or with a strong background noise it works poorly. To tackle this problem, the VAD2 mechanism of AMR is researched in detail and the possibility of introducing it into the G.729B is discussed. At the same time, some optimization work is also done. Through Matlab simulation, the optimized VAD2 is proved better by comparing it with the VAD algorithm of G.729B in both the high and low SNR, and its detection time is shortened greatly. So the optimized VAD2 can be used in G.729B.

关 键 词：VOIP G.729B 话音激活检测 信噪比 自适应多速率语音编码 

分 类 号：TN912.3[电子电信—通信与信息系统]