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Energy-Detection Model for Monaural Auditory Detection

1962; Acoustical Society of America; Volume: 34; Issue: 12 Linguagem: Inglês

10.1121/1.1909139

1520-9024

Sheila M. Pfafflin, M. V. Mathews,

Speech and Audio Processing

In the auditory detection of a sinusoidal signal in the presence of random noise, it has previously been demonstrated that the presence of a “pedestal” or background sinusoid of the same frequency and phase as the signal increases detectability. This increase was confirmed in a two-interval forced choice experiment in which a 1000-cps sinusoid was present in one of two 0.1-sec intervals, and the noise plus pedestal were present in both intervals. Pedestals of moderate intensity in phase with the signal increased detectability. Pedestals in quadrature (90° out of phase) with the signal did not improve detectability. Very large pedestals decreased detectability irrespective of phase. A simple energy-detection model was developed and its performance compared with the experimental results. The model consists of a bandpass filter, a square-law element, and an integrator. The probability of correct detection varies with signal level in a manner similar to the auditory results. Detectability is improved by an in-phase pedestal and approaches that of a correlation detector in the limit of infinite pedestal. Detectability is not improved by quadrate pedestals. The model can be modified to predict the decreasing detectability with large pedestals.