System for reproducing data with increased accuracy by reducing difference between sampled and expected values
US6603722B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2000 |
| Grant date | Aug 5, 2003 |
| Priority date | — |
| Expiry date | Oct 19, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10515
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A data reproduction system, which determines reproduced data based on comparison results of path metrics calculated in accordance with a Viterbi algorithm based on branch metrics calculated from expected values and a sampled value of a readout signal, includes an expected value setting unit for variably setting the expected values used for a calculation of the branch metrics in order to perform a Viterbi detection process without being easily affected by the transient response, offset variation, phase error and nonlinear torsion component of the readout signal. The readout signal is obtained from a recording medium on which data is recorded in accordance with a recording signal of a partial response waveform, the expected values are determined by the partial response waveform, and the sampled value is obtained by sampling the readout signal at a predetermined frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.