Method and apparatus for calibrating data-dependent noise prediction
US6889154B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 2003 |
| Grant date | May 3, 2005 |
| Priority date | — |
| Expiry date | Mar 28, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Disclosed herein is an apparatus and method of calibrating the parameters of a Viterbi detector 138 in which each branch metric is calculated based on noise statistics that depend on the signal hypothesis corresponding to the branch. An offline algorithm for calculating the parameters of data-dependent noise predictive filters 304A-D is presented which has two phases: a noise statistics estimation or training phase, and a filter calculation phase. During the training phase, products of pairs of noise samples are accumulated in order to estimate the noise correlations. Further, the results of the training phase are used to estimate how wide (in bits) the noise correlation accumulation registers need to be. The taps [t[k], t[k], t[k]] of each FIR filter are calculated based on estimates of the entries of a 3-by-3 conditional noise correlation matrix C[k] defined byCij[k]=E(ni−3nj−3|NRZ condition k).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.