Patent · US Expired

Disk servo pattern writing

US7307807B1 · kind B1 · utility

37Cited by
15References
46Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 11, 2004
Grant dateDec 11, 2007
Priority date
Expiry dateDec 7, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B20/14
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Systems and techniques to write servo patterns on machine-readable media. In general, in one implementation, the technique includes: obtaining timing information from a spiral servo reference track on a machine-readable medium to determine head position, and generating a servo track with servo information based on the determined head position. Obtaining the timing information can involve determining a peak position of a diamond-shaped waveform and identifying occurrences of a timing-reference symbol in the spiral servo reference track. Moreover, identifying occurrences of the timing-reference symbol can involve decoding an encoded repeating pattern using multiple framings, correlating signal samples that indicate pattern transitions with valid pattern transitions as defined by the encoding, accumulating the transition pattern correlations for the multiple framings, selecting one of the multiple framings as a correct framing, and determining a waveform polarity for the signal.

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