Subcarrier frequency division multiplexing of modulated backscatter signals
CA 2219268 A1 · Owner: Maclellan, John Austin · Inventors: Maclellan, John Austin; Shober R. Anthony; Wright, Gregory Alan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In accordance with the present invention the communication system, comprises an Interrogator and one or more Tags. The Interrogator generates a modulated carrier signal by modulated a first information signal onto a radio signal. The Interrogator transmits a downlink signal which comprises the modulated carrier signal and the radio signal. A Tag receives and processes the downlink signal. Specifically the Tag demodulates the first information signal from the modulated carrier signal and generates a second information signal typically based on the contents of the first information signal. The second information signal is used to modulate a subcarrier signal, thereby generating a modulated …
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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 October 23, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 23, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 2019.
- 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
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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.