Electrical audio signal processing systems and devices – Noise or distortion suppression – Interpolation
Patent
1995-11-13
1997-08-19
Isen, Forester W.
Electrical audio signal processing systems and devices
Noise or distortion suppression
Interpolation
395 236, H04B 1500
Patent
active
056596227
ABSTRACT:
A noise suppression system implemented in communication system provides an improved update decision during instances of sudden increase in background noise level. The noise suppression system, inter alia, generates an update by continually monitoring the deviation of spectral energy and forcing an update based on a predetermined threshold criterion. The spectral energy deviation is determined by utilizing an element which has the past values of the power spectral components exponentially weighted. The exponential weighting is a function of the current input energy, which means the higher the input signal energy the longer the exponential window. Conversely, the lower the signal energy the shorter the exponential window. The noise suppression system also inhibits a forced update during periods of continuous, non-stationary input signals (such as "music-on-hold").
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Isen Forester W.
Motorola Inc.
Sonnentag Richard A.
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