This paper states in details several key techniques such as amplification &AGC, anti-confusion filterings, the digitalization of the speech signals, characteristic selection etc n the pre-processing technique of the speech signal.

• 本文详细阐述了语音信号预处理技术中的放大和增益控制、反混叠滤波、语音信号数字化、特征提取等几项关键技术。