Adaptive echo canceller
CA 2020804 C · Owner: Kakuishi, Mitsuo · Inventors: Fukui, Hirokazu; Chujo, Kaoru; Kakuishi, Mitsuo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An adaptive echo canceller for suppressing an echo in an input signal by a pseudo echo includes a, pseudo echo generation filter having a predicted impulse response sequence of an echo path as filter coefficients thereof for generating a pseudo echo, a coefficient renewal part for adaptively renewing the filter coefficients of the pseudo echo generation filter and a, part for suppressing an echo by the pseudo echo which is generated by the pseudo echo generation filter. The coefficient renewal part includes a part for dividing renewed filter coefficients into a plurality of groups each having a certain number of renewed filter coefficients, and a part for successively selecting one group …
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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 July 10, 1990 and granted August 2, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 10, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 10, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.