Noise reduction system
CA 2005117 C · Owner: Hataoka, Nobuo · Inventors: Amano, Akio; Aritsuka, Toshiyuki; Ichikawa, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A noise reduction system used for transmission and/or recognition of speech comprises a speech analyzer analyzing a noisy speech input signal thereby converting the speech signal into feature vectors (a set of feature quantities) such as autocorrelation coefficients, and a neural network receiving the feature vectors of the noisy speech signal as its input and extracting from a codebook, generated by previously clustering a set of feature vectors of a noise-free speech signal (a table storing prototype vectors corresponding to the feature vectors of the noise-free speech signal together with corresponding indices of the prototype vectors), the index of the prototype vectors corresponding to …
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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 11, 1989 and granted March 1, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 11, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 11, 2011.
- 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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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.