Digital signal processing apparatus
CA 2248480 A1 · Owner: Sumitomo Electric Industries, Ltd. · Inventors: Funada, Tomoyuki; Toyoda, Shigeharu; Tawa, Katsuhisa
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Prior art digital signal modulation apparatuses for digital orthogonal modulation or VSB filter modulation required high-speed digital ICs for sine and cosine calculation and multiplication, due to the high carrier frequency. The present modulation apparatus modulates digital signals by a complex modulation wave of frequency f c which is determined to be f c =f if - n ~ f symb, where f if is a carrier frequency and f symb is a symbol rate of input digital signals. The apparatus raises the frequency of the input signal by multiples of f symb with an interpolation device, selects only a frequency range of the carrier frequency f if with a complex bandpass filter BPF, chooses a real part or an …
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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 September 28, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 28, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 28, 2020.
- 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.