Stereophonic acoustic echo cancellation using nonlinear transformations
CA 2215592 C · Owner: Morgan, Dennis Raymond · Inventors: Morgan, Dennis Raymond; Benesty, Jacob; Hall, Joseph Lindley Ii
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for estimating individual impulse responses for a stereophonic communication system, such as a teleconferencing system which involves, selectively reducing the correlation between the individual channel signals of the stereophonic system. Selective reduction of stereophonic source signal correlation advantageously results in the estimation of individual impulse responses of a receiving room of the stereophonic communication system. The selectively reduced-correlation source signals are provided to conventional adaptive filters and the receiving room loudspeakers. Automatic echo cancellation is performed in a conventional fashion but, on the selectively …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed September 16, 1997 and granted December 5, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 16, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 16, 2019.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.