Adaptive modulation method
US6359934B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 19, 1999 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Mar 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0059
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Each modulation level estimating unit calculates mean or variance of a carrier wave power for received signals to which no modulation level information is added when being transmitted, and calculates the difference between the calculated mean or variance and a mean or variance at each modulation level, as one of likelihood function values &Lgr;ML#1 through &Lgr;ML#X of each modulation level. A maximum likelihood function value selector selects the modulation level corresponding to the likelihood function value having the maximum likelihood value from among the likelihood function values, and makes a data selector select as a demodulation signal the output of a modulation level demodulating unit, which corresponds to the selected modulation level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.