Method and apparatus for reducing residual far-end echo in voice communication networks
CA 2189489 C · Owner: Velardo, Patrick Michael, Jr. · Inventors: Wynn, Woodson Dale; Velardo, Patrick Michael, Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus are described for reducing in communication, signals received by a local network from a remote network (FAR-IN signals) thatenergy content that is attributable to echoes of signals transmitted into the local network (NEAR-IN signals). This is achieved in part, by generating a time-varying, TEMPLATE signal which represents the smoothed energy content of NEAR-IN signals delayed according to the echo path and attenuated by an estimated echo transmission loss. A non-linear processor passes the FAR-IN signal substantiallywithout attenuation if it exceeds the TEMPLATE but attenuates the FAR-IN signalif it lies within a defined range below the TEMPLATE.
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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 November 4, 1996 and granted July 31, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 4, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 4, 2018.
- 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.