Frame structure for a QAM system
US9160601B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2014 |
| Grant date | Oct 13, 2015 |
| Priority date | — |
| Expiry date | Jun 30, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/42607
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A novel framing method for a variable net bit rate digital communications system that utilizes a set of different QAM constellations and punctured trellis code combinations, each combination designated as a mode. This frame structure has a variable integral number of QAM symbols per frame depending on the selected mode, but the number of bytes and Reed-Solomon packets per frame is constant. This is achieved even though the number of data bits per QAM symbol for some modes is fractional. Also the number of trellis coder puncture pattern cycles per frame is an integer for all modes. This arrangement simplifies the synchronization of receiver processing blocks such as the Viterbi decoder, de-randomizer, byte de-interleaver, and Reed-Solomon decoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.