Write precompensation optimization in a PRML channel using a selected PRML signal level
US5583705A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 17, 1995 |
| Grant date | Dec 10, 1996 |
| Priority date | — |
| Expiry date | Nov 17, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1258
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Write precomposition optimization for a partial response maximum likelihood ("PRME") magnetic recording chapel adapted to a mass production environment. Optimal write precompensation may be determined by writing a tribit data pattern known to produce worst case nonlinear transition shift ("NLTS") onto a magnetic recording medium; reading back the recorded data pattern; and calculating the mean-squared error ("MSE") for one or more of the equalized data sample levels associated with the PRML channel to be optimized. The writing and reading back process is repeated with varying amounts of precompensation applied to the written pattern. The optimal amount of write precompensation is determined eider by minimizing the MSE for a selected sample level or by minimizing MSE between the middle and the upper or lower of the ternary PRML sample levels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.