Charging a transponder in a security system
CA 2232256 A1 · Owner: Ford Motor Company Of Canada, Limited · Inventors: Campbell, Scott Owen; Perkins, Luke Aaron; Laude, David Philip
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A transponder is adaptively energized using a charging electromagnetic field created by a transceiver in a security system. A partial charging electromagnetic field is transmitted providing a plurality of spaced frequency components so that one to the spaced frequency components energizes the transponder by an amount causing it to produce a partial transmission which provides an calibrated signal for identifying a frequency upon which the transponder will be transmitting. A full charging electromagnetic field limited to a single frequency component is transmitted to the transponder determined in response to a frequency calibration signal received from the transponder.
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 March 16, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 16, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 16, 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.