Channel control in a wavelength division multiplexed communications network
CA 2277811 A1 · Owner: Alcatel · Inventors: Haxell, Ian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Multi-wavelength optically amplified systems require selected premphasis of channel powers to equalise signal to noise ratios at the receive terminal end. In the present invention, a channel control circuit for an optical wavelength division multiplexed (WDM) communications system (14) comprises an optical coupler (2) having an optical input, an optical output and an arm coupled to a wavelength multiplexer (5). The multiplexer (5) de-multiplexes an optical signal into a number of separate channels which are then each coupled to a respective optical attenuator (6n) which processes the individual channel and then returns them to the optical output via the multiplexer (5).
Read the whole patent
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 November 23, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 23, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 23, 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
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.