Code-division multiplex communication transmitting apparatus and receiving apparatus and method thereof
US6853631B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 1999 |
| Grant date | Feb 8, 2005 |
| Priority date | — |
| Expiry date | Oct 12, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B2201/70701
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A phase θI1, . . . , θQ1, . . . uniquely determined for each channel is assigned to a carrier for each channel used when data I1 . . . , Q1, . . . , to be distributed among different channels are modulated. By appropriately modifying the phase of a carrier for each channel, signal points can be located in a narrower region than in a conventional region, and thereby the difference in amplitude between a signal point with a minimum amplitude and a signal point with a maximum amplitude can be reduced. Thus, the amplitude range of a signal to be covered by an amplifier for transmitting a transmission signal is reduced, and thereby an amplifier with a linearity that is not high can be used for the amplifier. Accordingly, even if the number of signal points increase, there is no need to use a large high-power amplifier, and thereby the small power and small size of the apparatus can be realized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.