Patent · US Expired

Media noise optimized detector for magnetic recording

US7173783B1 · kind B1 · utility

83Cited by
5References
100Claims
0Family size

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Key dates

Filing dateSep 20, 2002
Grant dateFeb 6, 2007
Priority date
Expiry dateNov 27, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/03197
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A media noise optimized (MNO) detector for a read channel compensates for pattern dependent media noise, and compensates for nonlinearities from many sources such as residual MR nonlinearity, residual nonlinear transition shift, partial erasure, write-induced nonlinearity, and steady-state mis-equalization. The MNO detector is implemented by adjusting a conventional Viterbi detector branch metric so that the channel output value (ideal value) can be a nonlinear function of the state/branch bits, and the branch metric scaling factor is a function of the state/branch. For a given state/branch, the ideal value is the mean of analog-to-digital converter samples for the pattern corresponding to the state/branch, and the branch metric scaling factor is proportional to the noise variance for the pattern corresponding to that state/branch.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.