DTMF Signal Detection System Based On The TMS320VC5402

This paper introduces in detail the hardware and software of the DTMF signal detection system. For the problems from the traditional DTMF detection plans, the parameter optimized Goertzel algorithm is proposed and used in this detection system, from which the satisfied detection results are obtained. The main work of this thesis are expressed as follows:1. In the first part, the research background and the generating principle of the DTMF signals are presented. Then, the traditional detection methods and their disadvantages are outlined in this paper. In order to solve these problems, the optimized Goertzel algorithm is proposed and applied in the DSP5402 detection system.2. The hardware design of the DSP5402 detection system is studied deep. Apart from introducing the function of the DTMF signals detection system and its block diagram, this paper describes the whole designing procedure of the DSP5402 detection system in detail, including the DSP5402 minimum unit system design, SHL206, CPLD unit circuit, external data and program memory expansion and etc. Finally, the whole circuit design of the DSP5402 detection system is presented.3. The analysis and optimization of the Goertzel algorithm from the math's aspect are described in this thesis. The principle of the Goertzel algorithm is briefly introduced at first. In addition, the advantage on the computation of the Goertzel algorithm compared with the traditional detection methods is described. Then, the number of samples N in the Goertzel algorithm is optimized, which has a great influence on the detection results.4. To facilitate the verification of the correctness and effectiveness of the optimized Goertzel algorithm a graphical user interface is constructed. And the whole verification procedure is done in the MATLAB environment, which lays a theoretical foundation on the software design of the DSP5402 detection system. 5. The software design of the DSP5402 detection system is discussed in detail. The software design flow diagram of the whole detection system is introduced at the beginning in this part. Then, the software initialization of the hardware detection system and the CPLD timing is described. Besides, the software design of the Goertzel algorithm in C language is presented. Further more, the detection results are analyzed in the CCS environment. At last, the final work of the DSP5402 hardware detection system is elaborated in this thesis.