A method of effecting random access in a mobile radio system
CA 2125389 C · Owner: Telefonaktiebolaget Lm Ericsson · Inventors: Dahlin, Jan Erik Ake Steinar; Muller, Walter Gerhard Alois
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for random access in a time divided mobile radio system, for instance an FDMA/TDMA system which, includes digital traffic channels and control channels which are organized so that four traffic channels and two control channels are included in a TDMA-frame. A base station transmits continuously flags in the time slots of the control channels. A mobile station desiring access to the system responds by sending a first message word in the time slot indicated by the base station in a first flag. When the mobile station wishes to transmit several message words the, base station reserves one or more time slots to this end by transmitting the first flag, although this flag now states that …
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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 12, 1993 and granted February 5, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 12, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 12, 2015.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.