Control of avalanche photodiodes bias voltage
CA 2476779 C · Owner: Butler, Graham · Inventors: Butler, Graham; Nicholls, Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical communications system uses forward error correction (FEC) to correct errors in signals carried by the system. Optical signals on the system are dropped at nodes and converted to electrical signals by avalanche photodiodes (APDs) at the node receivers. A FEC chip operates on the electrical signal to correct errors. The error rate is used to control the APD bias voltage which affects signal noise and therefore error rate. The errors , in a predetermined interval are counted and a determination made as to whether the error rate is rising with time. The bias voltage is derived from the value of a counter whose count is incremented each interval. If the error rate is rising, …
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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 March 11, 2003 and granted November 20, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 11, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 11, 2025.
- 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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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.