Efficient decoding of digital DTMF and R2 tone signalization

In this paper the implementation aspects of decoding digital DTMF and R2 signalization tones are analyzed. First, a short review of specifications for DTMF and R2 signalization proposed by ITU-T is made, following by short review of decoding techniques applied in practice. Finally, a new computationally efficient method is proposed and experimentally verified. This method has distinct advantages in multichannel decoding systems and permits decoding in both signaling systems.

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