研究DTMF信号的产生以及基于Goertzel算法的接收原理，并使用MATLAB编程实现DTMF拨号系统的信号发生及接收。-The study of the production of DTMF signal and receiving based on Goertzel algorithm principle, and USES MATLAB programming to realize the DTMF dialing and receiving signal of the system.