Selective filtering for co-channel interference reduction
CA 2220239 C · Owner: Nortel Networks Limited · Inventors: Wang, Rui R.; Tong, Wen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Complex signal samples (s(k)) of an input signal are supplied via a frequency down-shifter (23) to a digital filter (24) and to a time-frequency transform unit (28) which produces a plurality of frequency components (S1(k) to S6(k)) each associated with a respective frequency band (1=1 to 6) within a bandwidth of the input signal. Thefrequency component having the maximum momentary energy is determined (29 30) to, determine the down-shifting frequency for the associated frequency band to be filtered and to determine a complementary up-shifting (25) following the digital filter to produce an output signal (f(k)). The filter can be a bandpass filter or a bandstop filter especially, for …
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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 November 5, 1997 and granted July 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 5, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 5, 2019.
- 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.