Spread spectrum random access systems and methods for time division multiple access radiotelephone communications systems
CA 2247279 C · Owner: Hassan, Amer · Inventors: Hassan, Amer; Reinhold, Stanley L.; Massingill, Larry W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a time division multiple access (TDMA) radiotelephone communications system, a spread spectrum random access channel signal representing a random access message is communicated from a radiotelephone to a central station according to a spreading sequence. In response a TDMA radiotelephone , communications channel is assigned to the radiotelephone. A time division multiplexed radiotelephone communications signal is communicated between the radiotelephone and the central station on the assigned TDMA radiotelephone communications channel over a time division multiplexed carrier frequency band. Preferably, in communicating the spread spectrum random access channel signal, a random …
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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 April 3, 1997 and granted January 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 3, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 3, 2019.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.