Encryption system for digital cellular communications
CA 2087616 C · Owner: Telefonaktiebolaget Lm Ericsson · Inventors: Dent, Paul Wilkinson
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system for generating a pseudo-random bit sequence which may be used in enciphering digital data prior to transmission or storage of the data. The bit sequence is generated by expanding a plurality of secret ket bits in a manner suitable for implementation with a conventional microprocessor arithmetic logic unit (ALU). The system of the present invention may be used, for example to secure, voice data communications between a base station and a mobile station in a digital cellular communications system.
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 July 18, 1991 and granted April 27, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 18, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 18, 2013.
- 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.