Detector DTMF Baseado em Modelagem Auto Regressiva

Thiago T. P. Oliveira, Leonardo S. Resende, Raimes Moraes

DOI: 10.14209/sbrt.2009.57868

Evento: XXVII Simpósio Brasileiro de Telecomunicações (SBrT2009)

Keywords: detecção sinais DTMF processo autoregressivo

Abstract

This work presents an alternative method of DTMF (Dual Tone Multi-Frequential) detection based on Adaptive Pole Estimation technique proposed by A. Nehorai and D. Starer [1]. It is able to estimate directly the roots of the characteristic equation (i.e. the poles) describing an autoregressive process that, in the case, correspond to the frequency values of the sine waves composing the DTMF tones. The proposed DTMF detector was tested with a wave file of MITEL CM7291 Test Tape and compared to detectors based on Goertzel algorithm. It has demonstrated to be more robust to the interferences than the traditional ones, besides to comply with ITU-T Recommendation Q.24 requirements.

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