一种结合Subband-NDFT和改进Goertzel滤波器的DTMF解调算法(英文)

A New Algorithm Combining Subband-NDFT and Modified Goertzel Filter to Detect DTMF Signal

基于Goertzel逻辑判断算法[1],提出了一种将Goertzel逻辑判断和Subband-NDFT相结合的新的解调DTMF信号的算法.Subband-NDFT通过放弃高频分量达到快速计算DFT的目的.软件仿真表明新的算法具有比Goertzel逻辑判断算法更快的解调速度,并且满足ITU在SNR上对DTMF信号的规定.

Based on Goertzel NDFT Logical Judgment algorithm, a novel algorithm combining subband non-uniform discrete Fourier transform （Subband-NDFT or SB-NDFT） and Goertzel NDFT Logical Judgment is presented in the article. The SB-NDFT achieves fast discrete Fourier transform （DFT） via abandoning high-frequency components. It is demonstrated that the new algorithm is faster than Goertzel NDFT Logical Judgment in decoding dual tone multi-frequency （DTMF） and fulfills the ITU （International Telecommunication Union） requirement in respect of SNR of DTMF.