Radio communication system
US4665532A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 1985 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Jan 22, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/362
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A radio communication system using a QAM system. In the transmission system, the data of each channel to be transmitted is divided into data groups having frame slots. When the polarity of the mean value of a data summed in a present data group is the same as the polarity of the mean value of the deviation of all data group coming before, all data in the present data group is inverted, a direct current component and a lower frequency component near the direct current component are suppressed, and carrier waves are injected after encoding. In the receiving system, a decoder decodes a received signal to obtain the original data before the encoding by the transmission system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.