Apparatus, method and system for correlated noise reduction in a trellis coded environment
US6934345B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 2001 |
| Grant date | Aug 23, 2005 |
| Priority date | — |
| Expiry date | Apr 4, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03503
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An apparatus, method and system are provided for correlated noise reduction, in a trellis decoding environment, such as second generation HDSL, in which crosstalk impairments may be significant. The preferred embodiments provide equalization and correlated noise reduction, utilizing a training period to generate corresponding coefficients, and utilizing two different training error signals. In addition, the apparatus method and system also provide continued and adaptive correlated noise reduction during data transmission, utilizing two additional error signals, a trellis error signal and a tentative error signal. The trellis error signal is a decision error of a selected previous state of a selected trellis path, in which the selected trellis path has a smallest cumulative error of a plurality of trellis paths, and the selected previous state is preferably the immediately previous state. The tentative error signal is formed as a difference between a delayed, tentative symbol decision and a delayed received data signal subsequent to equalization, in which the delay is preferably one symbol time. The various embodiments may be utilized with trellis encoding, with or without data prec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.