一种基于实时噪声估计的改进谱减法

针对非平稳噪声环境和低信噪比下的语音增强，提出了一种基于实时噪声估计的改进谱减法。该方法首先利用临界带特征矢量距离进行端点检测，然后利用低频区和高频区带噪语音特性定义一个时变的调节系数，该系数结合端点检测可以实时地对噪声的估计值进行更新，从而达到快速跟踪外界环境变化的目的。仿真结果表明，该方法在抑制背景噪声、提高信噪比、减少语音失真等方面优于传统的语音增强方法。

Improved Spectral Subtraction Based on Real-time Noise Estimation

Aiming at speech enhancement under non-stationary noise environment and low SNR, an improved spectral subtraction based on real-time noise estimation was proposed. First, voice activity detection was carried out based on selected sub-bands vector distance, and then a real-time adjustment coefficient was defined through noisy speech properties of low-frequency regions and high-frequency regions. The combination of coefficient and voice activity detection could realize the updating of noise estimate.The method allowed tracking the time variation of noise environment.The experiment showed that the method was more effective in reducing background noise, improving SNR and decreasing speech distortion than traditional speech enhancement methods.