The software generation and the comparison of decoding approach of DTMF signal

Dual-tone multi-frequency signal has been widely used in the modern communication systems. This paper gives a detailed analysis of the characteristics of the dual-tone multi-frequency signal and the method of analyzing the dual-tone multi-frequency signal by software. Using Matlab this paper analyses the dual-tone multi-frequency signal, designs a graphical interface imitating telephone using GUI toolbox, generates the DTMF signal through sine wave superposition, introduces the three frequency domain decoding approach, FFT, Goertzel Algorithm, improved Goertzel Algorithm based on NDFT, and gives the results of simulation of the three algorithms, in the end, analyses the advantages and disadvantages of the three algorithms, compares the effectiveness and complexity of the three algorithms. The study of this paper supplies a software application without hardware for studying digital signal processing.