Device and method for efficient decoding with time reversed data
US6272187A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 27, 1998 |
| Grant date | Aug 7, 2001 |
| Priority date | — |
| Expiry date | Mar 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0061
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A novel device which efficiently decodes data encoded with a cyclic code in communications systems where a convolutional code is applied after the cyclic code during encoding. Specifically, the device accepts data provided in time reversed order by a Viterbi decoder which decodes the convolutional code. In a preferred version, the device employs linear feedback shift registers with multiple feedback paths. A set of multipliers corresponding to a set of coefficients is interposed in the feedback paths such that when data is shifted through the feedback shift registers, the device performs division by x for an input bit equal to 0, and, for an input bit equal to 1, performs division by x and then adds x.sup.k+m-1. The set of multipliers includes a set of weighting multipliers corresponding to coefficients of a weighting polynomial such that addition of x.sup.k+m-1 is performed for an input bit equal to 1. In another preferred version, the device compares a known initial state to a final state generated by shifting time reversed data through the linear feedback shift registers such that the final state equals the known initial state if there are no errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.