Noise suppression circuit
August 19, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesAutomatic background noise estimator for a noise suppression system Method and apparatus for adaptive audio resonant frequency filtering Network echo canceller Adaptive feedback system Apparatus with distortion cancelling feed forward signal Linear RF amplifier having reduced intermodulation distortion Method of transmitting low-power frequency hopped spread spectrum data Digital noise shaper circuit Noise reduction filter Echo canceller for non-linear circuits InventorsAssigneeApplicationNo. 10/223409 filed on 08/19/2002US Classes:704/226, Noise704/200.1, Psychoacoustic704/224, Normalizing704/227, Pretransmission704/228, Post-transmission704/233Detect speech in noiseExaminersPrimary: Chawan, VijayAttorney, Agent or FirmInternational ClassesG10L 21/00 (20060101)G10L 21/02 (20060101) AbstractAn adaptive noise suppression system includes an input A/D converter, an analyzer, a filter, and a output D/A converter. The analyzer includes both feed-forward and feedback signal paths that allow it to compute a filtering coefficient, which is input to the filter. In these paths, feed-forward signal are processed by a signal to noise ratio estimator, a normalized coherence estimator, and a coherence mask. Also, feedback signals are processed by a auditory mask estimator. These two signal paths are coupled together via a noise suppression filter estimator. A method according to the present invention includes active signal processing to preserve speech-like signals and suppress incoherent noise signals. After a signal is processed in the feed-forward and feedback paths, the noise suppression filter estimator then outputs a filtering coefficient signal to the filter for filtering the noise out of the speech and noise digital signal.Other References
Field of SearchAUDIO SIGNAL BANDWIDTH COMPRESSION OR EXPANSIONWith content reduction encoding Delay line AUDIO SIGNAL TIME COMPRESSION OR EXPANSION (E.G., RUN LENGTH CODING) With content reduction encoding Psychoacoustic SPEECH SIGNAL PROCESSING Noise Pretransmission Post-transmission Detect speech in noise Normalizing | |
