Electrical audio signal processing systems and devices – One-way audio signal program distribution – Public address system
Patent
1990-01-05
1991-04-30
Kemeny, Emanuel S.
Electrical audio signal processing systems and devices
One-way audio signal program distribution
Public address system
381 46, G10L 500
Patent
active
050125192
ABSTRACT:
Noise in a speech-plus-noise input signal is suppressed by splitting the input signal into spectral channels and decreasing the gain in the each channel which has a low signal-to-noise ratio (SNR). A voice operated switch (VOX) acts to detect noise-only input to gate a background noise (input signal) estimator and also to gate a residual noise (output signal) estimator. The gain in each of the channels is controlled by the current value (a posteriori) input signal SNR estimate, modified by the prior value (a priori) input signal SNR estimate, and smoothed as a function of the residual (output noise signal) estimate.
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Adlersberg Shabtai
Aizner Mendel
Berstein Alberto
Stettiner Yoram
Kemeny Emanuel S.
The DSP Group Inc.
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