双传声器系统中的风噪声抑制方法研究

Research for Wind Noise Reduction Method in Dual-microphone System

风噪声是自然界中最常见的一种噪声,严重影响着传声器拾音质量,并且其非平稳性使普通消噪方法(如谱减法等)不适用于风噪声抑制。本文分析了双传声器拾取的语声信号和风噪声信号的频域相干性,利用来自双传声器语声信号之间的强相干性和风噪声之间的弱相干性,采用Zelinski滤波器思路,考虑自由声场和扩散声场中风噪声和背景噪声的综合影响,设计了一种利用信号的相干性进行风噪声检测,进而准确估计风噪声相干系数的风噪声抑制滤波器。实验证明,文中提出的基于双传声器相干性原理的风噪声抑制方法较传统方法不仅在消噪性能上有较大提升,而且还具有运算量小、实时性强的特点,能够广泛应用于自由声场和扩散声场中的各类拾音系统。

Wind noise is the most common kind of noise in the nature, which will seriously reduce the quality of micro- phone recording. And because of its non-stationary characteristics, wind noise can not be suppressed by the common noise reduction methods, such as spectral subtraction and so on. In this paper, we analyze the spectral coherence of speech and wind noise from the dual-microphone, and then we take the idea of Zelinski post-fiher to design a wind noise reduction fil- ter, utilizing the strong coherence of speech and the weak coherence of wind noise between the two microphones. Also in the filter design, the combined effect of wind noise and background noise in the free sound field and the diffuse sound field is taken into consideration. The filter can detect the wind noise using the coherence of the signal and precisely estimate the wind noise coherence function. Experimental resuhs show that the wind noise reduction method based on coherence of dual- microphone system significantly improves the denoising performance by contrast with other traditional noise reduction meth- ods, also it has the characteristics of small computation and high real-time performance, which can be widely used in kinds of sound pickup systems.