改进DTMF信号检测方案在定点DSP上的实现

讨论了硬件实现双音多频(DTMF)信号检测方案的弊端，比较了MUSIC算法、SB-NDFT算法、FF T算法和Goertzel算法，给出了以改进Goertzel算法为核心的DTMF信号检测的DSP实现方案和 实测结果。实验结果表明，该方案有较好的检出率和抗干扰能力。程序全部使用汇编语言实 现，提高了系统运行的实时性和功能冗余度。

Implementation of a modified DTMF signal detection scheme with fixed-point DSP

The abuse of realizing DTMF(Dual Tone Multifrequency) signal detection scheme us in g hardware is discussed.Multiple signal classification(MUSIC) algorithm, SB-NDF T(Suband Nonuniform Discrete Fourier Transform) algorithm, FFT(Fast Fourier Tran sform) algorithm and the Goertzel algorithm are compared. Then, the DSP implemen tation scheme of DTMF signal detection with modified Goertzel algorithm as the c ore and test results are presented. Test results show that this scheme has a bett er detection rate and anti-interference capability. The whole program is written with assembly language so as to improve the real-time and functional redundancy ability of system.