数字信号处理中关于FFT变换的频谱的描述，及其对频谱的分析，该程序不是直接调用MATLAB中的FFT变换的函数，对整个过程给出了详细的编码-Digital signal processing on the spectrum of the FFT transform in the descr iption, and its spectrum analysis, the program is not called directly the FFT transform function in MATLAB, the detailed coding is given to the entire process