Noise cancelling method and apparatus for the same
CA 2228097 C · Owner: Nec Corporation · Inventors: Ikeda, Shigeji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A noise canceler of the present invention is of the type including an adaptive filter for generating a pseudo noise signal subtracting the pseudo, noise signal from a received signal to thereby output an error signal and, sequentially correcting the filter coefficient of the filter in accordance with the error signal. A second adaptive filter produces a second pseudo noise signal and a second error signal. A first and a second power mean circuit each calculates the signal power of the respective signal. A divider performs division with the resulting two kinds of signal power so that a signal-to-noisepower ratio is estimated. A comparator compares the estimated signal-to-noise power ratio …
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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 January 28, 1998 and granted December 18, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 2020.
- 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
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.