Digital signal processor for electronic article gates
CA 2033244 C · Owner: Obrea, Andrei · Inventors: Obrea, Andrei; Zemlok, Kenneth Carl
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A frequency swept electromagnetic field is generated in an interrogation zone and signals received from the interrogation zone are processed to detect the presence of a marker with a resonant tank circuit in the zone. Detection is determined by the use of averaging techniques and shape recognition persistence tables are generated whereby the background can be isolated.
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 27, 1990 and granted February 15, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 27, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 27, 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.