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.

通过STMF，IIR滤波器构建方法实现电话按键声音的功能-Through STMF, IIR filter construction method to achieve the functions of voice call button

dtmf signaling source code using matlab

用MATLAB仿真DTMF,分为生成和检测两个部分-use MATLAB to simulate the DTMF including generation and detection