Multi-channel echo cancelling method and a device thereof
CA 2124662 C · Owner: Hirano, Akihiro · Inventors: Hirano, Akihiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a multi-channel echo cancelling art enabling proper operation even if using a microphone not generating propagation delay difference between channels. The present invention comprises: a step of calculating a power of reception signal in each reception channel and selecting a reception channel of a reception signal having the biggest power; a step of generating an echo replica corresponding to an echo in each mixed signal generated by propagation of reception signals of the reception channels based on a reception signal of the reception channel selected in the previous step; and a step of cancelling the echoes from mixed signals in which the echoes are mixed …
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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 May 30, 1994 and granted March 23, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 30, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 30, 2016.
- 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.