Trellis coded modulation system for hdtv
CA 2181539 C · Owner: Citta, Richard W. · Inventors: Willming, David A.; Citta, Richard W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A trellis coded modulation system comprises a source of successive 2-bit data symbols X1, X2 arranged in a frame format wherein each frame comprises a plurality of data segments each including a plurality of groups of interleaved data symbols. Each group of interleaved data symbols is separately coded by a precoder and convolution encoder to derive coded output symbols Z0, Z1, Z, which are mapped to respective 8-level symbols for transmission together with periodically generated frame and segment sync symbols. The received signal may be filtered by a linear filter e.g. a, comb filter to reduce co-channel interference and each group of filtered symbols is applied to a respective first …
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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 June 29, 1995 and granted May 30, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 29, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 29, 2017.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.