Transmitter with nonlinearity correction circuits
CA 2074124 C · Owner: Matsushita Electric Industrial Co. Ltd. · Inventors: Matsumoto, Takayuki; Kosugi, Hiroaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a feedback loop, a modulation carrier signal is amplified or attenuated by a variable gain amplifier (2). A part of a transmission signal amplified by a power amplifier (3) is extracted by a monitor circuit (4), and is detected by an envelope detector (6). This transmission envelope signal and a distortion-free standard envelope signal produced from a standard envelope generator (7) are compared in an error detector (8). An error signal obtained by amplifying the error of the two signals and a DC voltage are added in an adder (9). A gain control terminal (11) of the variable gain amplifier (2) is controlled by using this adder output signal as the control signal. The envelope detector …
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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 July 17, 1992 and granted September 26, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 17, 2014.
- 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.