Method of quadrature-phase amplitude modulation
CA 1295700 C · Owner: Nortel Networks Limited · Inventors: Kennard, Paul Alan; Mcnicol, John Duncan; Middleton, Joseph Leslie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, A square array of signal points forming a QAM signal point constellation is modified by relocating signal points from corners of the square to positions extrapolated from the square array and at reduced distances from the origin, corresponding to reduced peak amplitude levels. The relocation is effected in a manner to maintain at least for a majority of the relocated points a Hamming distance of, one. To this end for a constellation of 22n points with n=4 or more, and points with I and Q amplitudes 1 3, 5, ...2n-1 units in the, square array a plurality of points in each quadrant are relocated to positions, relative to positions which they would have in the square …
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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
- Granted February 11, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 11, 2009.
- 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.