Noise canceling apparatus
CA 1293693 C · Owner: Nec Corporation · Inventors: Taguchi, Tetsu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In order to eliminate background noise infiltrating into an input audio signal, a noise-canceling apparatus includes: first and second acoustic pickups for primarily picking up the audio signal and noise, respectively; a filter receiving the output of the second acoustic pickup; a subtracter for subtracting the output of the filter, when the audio signal is silent from the, output of the first acoustic pickup; and a coefficient determination for determining coefficients of the filter so as to make the filter generate a noise signal corresponding to a signal generated by passing the noise through a transmission path having a transmission frequency characteristic from the noise source to 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
- Granted December 31, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 31, 2008.
- 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.