Multiple quadrature-phase amplitude modulating system capable of reducing a peak amplitude
CA 1251526 A · Owner: Nec Corporation · Inventors: Koizumi, Yutaka; Uchibori, Junichi; Ryu, Toshihiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a multiple QAM system in which a pair of quadrature-phase carrier signals is modulated by a first and a second input digital signal, each representative of N or less levels, into a quadrature-phase amplitude modulated signal having M signal points on a phase plane where M is equal to N2, a code converting unit (41) converts the digital signals according to a predetermined rule into a first and a second modulating signal for use in modulating the carrier signals with the M signal points arranged approximately at a circle of a diameter which is shorter than a diagonal of a square of a side corresponding to the N levels. In a counterpart demodulating system, a pair of demodulated signals is …
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
- Granted March 21, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 21, 2006.
- 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.