Digital transmission system
CA 2211215 C · Owner: Rockstar Bidco, Lp · Inventors: Tate, Christopher; Humphrey, Leslie Derek
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An orthogonal frequency division multiplex (OFDM) transmission system e.g. , for transmitting data traffic over a telephone subscriber twisted pair loop includes a transmitter for generating sets of time division samples in respective channels corresponding to an input data sequence comprising a series of bits, and a receiver coupled to the transmitter via the transmission path. The receiver incorporates a time variant digital filter having a plurality of elements one for each said channel and Fourier transform means , for recovering the data stream from the outputs of said filter elements. The time variant digital filter comprises a set of wavelet filters one for each transmission …
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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 August 16, 1996 and granted April 17, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 16, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 16, 2018.
- 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.