On the basis of analyzing noise property , this thesis emphasizes on two noise estimation methods : classical method based on voice activity detection ( vad ) and the latest method based on optimal smoothing and minimum statistics . some improvements have been proposed to enhance the vad ’ s performance based on lpc cepstrum coefficients 2 .在分析噪声特性的基础上,重点研究了基于语音活性检测和基于连续更新噪声谱的两种噪声参数估计方法,并提出了将能零积的思想应用到基于lpc倒谱系数的语音活性检测算法中。
This paper begins with an analysis of vad ( voice activity detector ) algorithm in amr vocoder ( speech codec standard in wcdma ) , with emphasis on the feature and fundamental principles of it , followed by a revised method that have better performance in simulation testo and is proved practicable in experimental test 本文首先对wcdma的语音编码标准? amr声码器中的语音端点检测算法进行了分析，重点探讨了算法的特点及其理论依据，其思想具有普遍意义，可以在信源压缩编码及其它需要高精度语音端点检测的应用场合中采用，具有较大的研究价值。
