说明：  处理宽带噪声的最通用技术是谱减法。它利用语音信号的短时平稳特性，从带噪语音的短时谱值中减去噪声的短时谱，从而得到纯净语音的频谱，达到语音增强得目的。
(Spectral subtraction is the most common technique to deal with wideband noise. It uses the short-term stationary characteristic of speech signal to subtract the short-term spectrum of noise from the short-term spectrum of noisy speech, so as to obtain the spectrum of pure speech and achieve the purpose of speech enhancement)