Method and apparatus for decoding M-PSK turbo code using new approximation technique
US6807238B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 2001 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Nov 19, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M13/6362
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The method of the present invention decodes a received symbol that represents data bits including message bits and parity-check bits. The method comprises (a) mapping the symbol onto a received signal point in a signal space, the signal point having an in-phase component (I) and a quadrature phase component (Q) in the signal space; (b) computing reliability information for each data bit, the reliability information associated with a distance di={square root over ((I−Ii)2+(Q−Qi)2)} between the received signal point (I, Q) and a reference constellation point (Ii, Qi) in the signal space, where i=0, 1, . . . , M−1 (for M an integer), by replacing calculation of (I−Ii)2+(Q−Qi)2 with calculation of 2(Ii×I+Qi×Q); (c) decoding the received symbol using the reliability information and a priori information to produce estimated message bits, the a priori information having a predetermined value in a first decoding; (d) calculating difference between received message bits and the estimated message bits to produce extrinsic information of estimated message bits; and (e) repeating at least once the mapping, computing, decoding and calculating, using the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.