Demodulator
CA 2206137 C · Owner: Nec Corporation · Inventors: Maeda, Shigeki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The demodulator of this invention is directed toward improving S/N ratio of the demodulator resulting from increase in the peak value of a received signal due to fading. The demodulator is composed of a roll-off filter (not shown), variable amplifier 16 multiplier 10, compressor 11, variable dynamic range analog/digital converter 12, transversal filter 13 expander 14, tap coefficient control circuit 15 and, signal level detector 17. Signal level detector 17 detects the magnitude of waveform distortion from the output of tap coefficient control circuit 15 and controls the gain of variable amplifier 16 and the dynamic range of analog/digital converter 12, thereby reducing nonlinear distortion …
Read the whole patent
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 May 26, 1997 and granted August 22, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 26, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 26, 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.
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.