Optical fibre communications system
CA 2070815 C · Owner: Fenning, Simon Charles · Inventors: Rosher, Paul Adrian; Reeve, Michael Harry; Bickers, Lawrence
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical fibre communications system includes an exchange (E) and a plurality of subscriber lines (1). The exchange (E) provides a plurality of services in different subcarrier frequencies (6 8, 9, 10). Each subscriber line (I) is provided with terminal apparatus (5) operable at different subcarrier frequencies and a control (11) at the exchange (E) tunes the terminal apparatus to transmit and/or receive on a particular frequency in response to a request. The request may be a signal from the terminal apparatus (5) or an incoming service request addressed to the particular terminal apparatus.
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 December 7, 1990 and granted August 18, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 7, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 7, 2012.
- 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.