设计产生一个连续信号，包含低频，中频，高频分量，对其进行采样，进行频谱分析，使用矩形窗设计不同特性的数字滤波器对信号进行滤波处理，分析所设计滤波器(画出了频率特性曲线)，并对信号进行滤波，画出滤波后信号的时域波形和频谱，并对滤波前后的信号进行对比，同时设计出了一个友好的人机交互界面。-Designed to produce a continuous signal, including low frequency, medium frequency, high frequency components, its sampling, spectral analysis, using rectangular windows of different characteristics of digital filter design the signal filtering, analysis of the designed filter (to draw the frequency characteristic curve), and signal filtering, to draw the filtered signal in time domain waveforms and frequency spectrum, and filtering the signal before and after comparison, the mean time, a friendly interactive interface.