远距离语音的激光相干获取及增强

基于激光相干探测理论建立了全光纤激光相干测振系统,并结合维纳语音增强技术实现了远距离、高质量语音信号的获取。首先,介绍了该系统的检测原理及光纤器件特性,搭建了全光纤激光相干测振实验系统检测发音者咽喉振动,从而实现远距离语音信号的获取。由于直接获取的语音信号受到严重的噪声干扰,采用基于最小控制递归平均算法估计噪声的维纳滤波来抑制噪声,提高语音质量。实验结果显示:激光相干测振系统可有效获取70m内的语音信号(检测喉咙振动还原语音);语音增强技术可有效抑制噪声,将信噪比提高5dB,并增强语音的清晰度。由此表明,该系统具备获取远距离、高质量语音信号的能力。

Acquisition and enhancement of remote voice based on laser coherent method

An all-fiber Laser Doppler Vibrometer (LDV) based on laser coherent method was investigated to acquire remote and high quality speech signals,combining with the Wiener speech enhancement technology.First,the heterodyne detection theory and the characteristic of fiber devices were introduced and the all-fiber LDV was established experimentally to detect the throat vibration,thus the remote voice was acquired.Whereas the direct acquisition of speech signals was prone to be disturbed by serious noise,the Wiener Filtering based on Minima Controlled Recursive Averaging (MCRA) was used to suppress the noise and improve the voice quality.The results indicate that the comprehensible speech signals within the range of 70 m can be obtained by the LDV.The speech enhancement technology can suppress the noise effectively and the Signal to Noise Ratio (SNR) was increased by 5 dB,thus the speech intelligibility was improved.This system has ability to acquire remote voice with high quality.