Subband echo cancellation method using projection algorithm
CA 2174366 C · Owner: Tanaka, Masashi · Inventors: Kojima, Junji; Tanaka, Masashi; Nakagawa, Akira
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A received signal is output to an echo path and at the, same time, it is divided into a plurality of subbands to generate subband received signals, which are applied to estimated echo paths in the respective subbands to produce echo replicas. The echo having propagated over the echo path is divided into a plurality of subbands to generate subband echoes, from which the corresponding echo replicas are subtracted to produce misalignment signals. Based on the subband received signal in each subband and the misalignment signal corresponding thereto a coefficient to, be provided to each estimated echo path is adjusted by a projection or ES projection algorithm.
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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 April 17, 1996 and granted March 27, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 17, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 2018.
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