Error correction circuit using character probability
US4349904A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 1980 |
| Grant date | Sep 14, 1982 |
| Priority date | — |
| Expiry date | Apr 18, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/0357
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An error correction circuit in a television receiver for receiving, for example, Teletext information, Viewdata information or information of comparable systems. The codes representing symbol information received by the receiver are classified into one out of two or more classes in dependence on the frequency of their occurrence, this classification being an indication of the extent to which it is probable that a received code is correctly received. In FIG. 1, a picture text television receiver has a receiving section, audio and video amplifiers 4 and 9 and a picture tube 10, 11. A text decoder 21 receives symbol information which is stored in a store 25 for display. An error detector circuit 40 including a comparison circuit 43 and two parity circuits 41 and 42, and checks for parity between newly received and already stored symbol information. A reliability circuit 60 is also included.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.