Digital echo canceller
CA 1318003 C · Owner: Van Gerwen, Petrus J. · Inventors: Kotmans, Hendrik J.; Van Gerwen, Petrus J.; Van De Laar, Franciscus A. M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Digital echo canceller A digital echo canceller 1 with a good protection against double-talk comprises a first filter 9 for the echo cancellation proper, a second adaptive filter 11 for making continuously adapted filter coefficients available to the first filter 9 and gate means 15 which will only apply the adapted filter coefficients to the first filter 9 if certain conditions are satisfied. In the echo canceller 1 a specific filter combination is used, in which the first filter 9 is a time-domain programmable filter (TDPF) and the second filter 11 is a frequency-domain block-adaptive (FDAF), and further means 20,20(1) are provided that are arranged in cascade with the gate means 15 for …
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
- Granted May 18, 1993. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 18, 2010.
- 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.