Position demodulator and position demodulation method
US8625230B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 9, 2012 |
| Grant date | Jan 7, 2014 |
| Priority date | — |
| Expiry date | Mar 29, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/2516
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
According to one embodiment, a position demodulator includes a demodulator, a phase corrector, and a position demodulating module. The demodulator demodulates a first demodulated signal and a second demodulated signal having a phase difference of 90 degrees from the first demodulated signal as a result of discrete Fourier transform operation on a read signal of a null servo pattern recorded in a servo area of a medium read out by a head. The phase corrector carries out correction to tilt respective vectors of the first demodulated signal and the second demodulated signal represented on a phase plane by a predetermined angle. The position demodulating module demodulates a positional signal for determining the position of the core of the head based on the first demodulated signal and the second demodulated signal corrected by the phase corrector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.