单音多频信号的产生和识别，采用FFT变换。应用于电话拨号。是学习数字信号处理的大作业。-Tone multi-frequency signal generation and recognition, the use of FFT transform. Applies to telephone dial-up. Digital Signal Processing is the study of large operations.

数字信号处理快速傅里叶变换C语言程序代码-Digital signal processing fast Fourier transform C language code

实现正弦信号的采样和快速傅里叶变换，效率非常高，可以运行。-Sinusoidal signal sampling and fast Fourier transform