Forward error correction using coding and redundant transmission
US4447903A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 22, 1981 |
| Grant date | May 8, 1984 |
| Priority date | — |
| Expiry date | May 22, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/004
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A forward error correcting digital transmission system having two separate transmission channels carrying redundant information. The signal on the first channel is encoded by combining each present bit with itself delayed m bits in time. The signal on the second channel may be encoded in the same manner only with a delay of n bits in time, or left without coding, i.e., n=0, in any case m and n are unequal integers. Both first and second channels are transmitted over separate transmission paths to the receiving terminal where each is independently decoded to obtain the original binary information from each received encoded signal. If an error is introduced into one of the channels during transmission, the encoded information necessarily contains an error in the present bit and its associated m or n delayed bit. Upon detection of an error by simple bit comparisons between the two decoded channels, the present decoded bit and its associated delayed decoded bit, if any, are changed in the apropriate channel in order to correct for the error.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.