Echo canceller
CA 2201013 C · Owner: Mitsubishi Denki Kabushiki Kaisha · Inventors: Ishii, Tomoko; Horie, Nobuyoshi; Suzuki, Shigeaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A counter 160 increments a count value every given period. An adaptive operation control unit 90 selects channels in.which adaptive operation are done from all the channels in obedience to the count value to output produced selection signals to AND circuits 151 to 15n. Double-talk detection circuits 81 to 8n judge the presence of double-talk states and output detection signals to the AND circuits. The AND circuits operate logical AND of the selection signals and the detection signals and output the logical AND results as control signals to filter coefficient updating circuits 71 to 7n. The filter coefficient updating circuits update or do not update filter coefficients stored in FIR filter …
Read the whole patent
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 March 25, 1997 and granted May 1, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 25, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 25, 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.
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.