Error detection and correction system for a stream of encoded data
US5742622A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Apr 26, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0068
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention provides a decoder of symbols of received data, the data being encoded according to a convolutional encoding scheme and transmitted through a communications channel. The data is punctuated according to a puncturing matrix, and has a plurality of state values which describe a sequence of state transitions. The decoder has a generation unit that accepts the received data for calculating metrics of the transitions thereof. A selector responsive to the generation unit selects a path of transitions corresponding to the path produced by a transmitter of the data stream. A traceback unit maintains historical information representative of sequential decision operations of the selector. A counter is provided for counting illegal state transitions of the path selected by the selector, and a control unit, responsive to the counter, determines a puncture rate and adjusts a puncture phase of the received data. The decoder can be used in a VLSI receiver circuit which is adapted to the reception of QPSK modulated data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.