A New Algorithm Combining Subband-NDFT and Modified Goertzel Filter to Detect DTMF Signal
Xi Zhang · Journal of Southwest University · 2008
Based on Goertzel NDFT Logical Judgment algorithm[1],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.