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Expired Canadian patentCanada

1:n ring-type signal protection apparatus

CA 2076844 C · Owner: Stalick, Victor J. · Inventors: Stalick, Victor J.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A system is illustrated that uses a spare or auxiliary add-drop muldem located at each end of N high capacity transport circuits to form a ring-type protection circuit using one additional high capacity transport. This is accomplished by using error detection circuitry to switch all of the auxiliary muldems to be normally in a high speed input/output circuit LOOPed condition but switching the auxiliary muldems on either end of a "bad" circuit to a THRU or open condition upon detection of a problem and allowing signals to be routed through the protection transport mechanism rather than the normal transport mechanism. 37

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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 August 25, 1992 and granted March 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 25, 2012.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 25, 2014.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledAugust 25, 1992
GrantedMarch 16, 1999
Term endedAugust 25, 2012
Patent numberCA 2076844 C
Classification (IPC)H04B3/46 +2 more

Timeline

Timeline From CIPO dates

1993199519971999200120032005200720092011Application filedAug 25, 1992Patent grantedMarch 16, 1999Term endedAug 25, 2012

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.