Additive pcm speaker circuit for a time shared isdn conference arrangement
CA 1331799 C · Owner: Bruce, Donovan A. · Inventors: Bruce, Donovan A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A time shared multiport conference arrangement includes an additive PCM speaker circuit. The additive PCM speaker circuit eliminates the need for loudest speaker detection and the last speaker memory of conventional conferencing arrangements. The additive PCM speaker circuitry operates in an on-line real time, environment to allow rapid conversion and summing of speakers' PCM voice samples. Since the PCM voice samples are logarithmic in nature, they are not directly combinable. The additive PCM speaker circuitry provides for converting the logarithmic PCM signals to linear form. Next, the linear signals of up to three conferees are buffered. Then the speakers' linear form samples are added …
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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 August 30, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 30, 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
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.