MATLAB软件平台下，利用函数wavread对语音信号进行采样，记住采样频率和采样点数；

2）画出语音信号的时域波形，对采样后的语音进行fft变换，得到信号的频谱特性；对语音信号分别加入正弦噪声和白噪声，画出加噪信号的时域波形和频谱图；

3）根据对加噪语音信号谱分析结果，确定滤除噪声滤波器的技术指标，设计合适的数字滤波器，并画出滤波器的频域响应；

4）用所设计的滤波器对加噪的信号进行滤波，在同一个窗口画出滤波前后信号的时域图和频谱图，对滤波前后的信号进行对比，分析信号变化；

-Under the MATLAB software platform, using the function wavread voice signal is sampled, the sampling frequency and sampling points to remember

2) Draw the speech signal in the time domain waveforms were sampled voice fft transform, to obtain the spectral characteristics of the signal　voice signals were added to the sinusoidal noise and white noise, plus noise signal when drawn-domain waveform and frequency spectrum

3) According to the speech signal plus noise spectral analysis to determine the filter noise filter specifications, design an appropriate digital filter and draw the filter frequency response

4) Use a filter designed to increase the signal-to-noise filtering, draw before and after filtering the signal in the time domain with a window display and the spectrogram of the signal before and after filtering comparative analyzes signal change