Apparatus for reducing the risk of undesirable parameter drift of an adaptive filter used for echo cancellation
CA 2125658 A1 · Owner: Telefonaktiebolaget Lm Ericsson · Inventors: Andre, Tore Mikael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Apparatus for reducing the risk of undesirable drifting of the parameters, so-called bursting, of an adaptive echo filter, which is coupled between a receiving branch and a transmitting branch included in a four-wire loop. A difference signal which contains no echo from the receiving branch is generated in the transmitting branch in a known manner. The apparatus includes an adaptive filter which is coupled between the transmitting branch and the receiving branch and which functions to generate a compensation signal from the difference signal when transmitting narrowband signals from a near-end. The compensating signal is subtracted from a signal which appears in the receiving branch and the …
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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 December 17, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 17, 2014.
- 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.