System for modulating/demodulating digital signals transmitted with encoded modulation
US5307377A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 1991 |
| Grant date | Apr 26, 1994 |
| Priority date | — |
| Expiry date | Oct 8, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0059
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Encoding and decoding devices (5, 105) influencing digital signals transmitted with encoded modulation. For the encoding a channel encoder (12) performs a code concatenation to distribute the protection redundancy bits over various symbol periods of the encoded modulation, for example, over two multiplexed 16 QAMs. A source encoder (11) may effect a reduction of the input bit rate. A differential encoder (31) may be used for the encoding so as to ensure the detection of the phase rotation invariance of the code. At the receiver end a decoding device (105) performs the corresponding operations in reverse. The invention may be used for digital signal transmission of: television, microwave, mobile radio signals, for storage on compact disc or on digital video recorder, for communication between computers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.