说明：  对一段语音信号进行读入，并加入高斯白噪声，输出原始信号和噪声信号的频谱，进行分析比较，最后去掉噪声，再对频谱进行分析。
(Read a section of the voice signal, and add the Gaussian white noise, the output of the original signal and noise signal spectrum, the analysis and comparison, and finally remove the noise, and then the spectrum analysis.)