Electronic article surveillance system with comb filtering and false alarm supression
CA 2232575 C · Owner: Bettine, Dale R. · Inventors: Frederick, Thomas J.; Bettine, Dale R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A signal received in an electronic article surveillance system (100) is combfiltered (150, 150') to remove interference. A second comb-filtering fucntion (154, 154') is provided to detect occasions when the first comb-filtering generates ringing artifacts in response to impulsive noise. Alarm indications (133) are inhibited at times when the artifacts due to impulsive noise are detected. Bandwiths of the filtering functions are adjustable in response to operator input (182).
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 13, 1996 and granted December 31, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 13, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 13, 2018.
- 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.