Dynamic magnetic information storage or retrieval – Automatic control of a recorder mechanism – Controlling the head
Patent
1997-08-26
1998-10-06
Psitos, Aristotelis M.
Dynamic magnetic information storage or retrieval
Automatic control of a recorder mechanism
Controlling the head
360 7705, 360 48, G11B 5596
Patent
active
058186590
ABSTRACT:
A digital servo control system for a disk drive provides asynchronous servo information signal demodulation. The system includes a digital demodulator having a digital squarer that removes any phase component of the digitized servo information signal and includes a burst signal accumulator that accumulates the squared terms according to respective burst timing intervals to produce a digital, quadrature position error signal (PES). The demodulator also can include a filter comprising a harmonic notch filter preferably implemented as a Hilbert Transform filter. Alternatively, the demodulator does not include a filter and squarer and, instead, the squarer comprises a sum-and-squarer that sums the squares of odd and even digitized samples. A split burst servo pattern for the servo control system is comprised of half-width transitions that can be written in a single pass of a recording head and therefore has no phase misalignment between adjacent flux patterns.
REFERENCES:
patent: 4669004 (1987-05-01), Moon et al.
patent: 4740736 (1988-04-01), Sidman et al.
patent: 4783705 (1988-11-01), Moon et al.
patent: 4896240 (1990-01-01), Moriya et al.
patent: 5050016 (1991-09-01), Squires
patent: 5089757 (1992-02-01), Wilson
patent: 5170299 (1992-12-01), Moon
patent: 5345342 (1994-09-01), Abbott et al.
patent: 5453887 (1995-09-01), Negishi et al.
"Quad Burst Servo Needing No Sync ID and Having Added Information," IBM TDB vol. 33, No. 3B, pp. 198-200, Aug. 1990.
D. Freitas, G. Herbst and M. Moser, "Asynchronous Quadrature Burst Position Error Demodulation Technique," IBM Technical Disclosure Bulletin, vol. 34, No. 5, Oct. 1991, pp. 406-407.
C. C. Liu, "Quad-Burst Servo Pattern," IBM Technical Disclosure Bulletin, vol. 22, No. 12, May 1980, pp. 5436-5438.
W. A. Herrington and F. E. Mueller, "Quad-Burst PES System for Disk File Servo," IBM Technical Disclosure Bulletin, vol. 21, No. 2, Jul. 1978, pp. 804-805.
Cheung Wayne Leung
Liu Chung Chuan
Mueller Francis Edward
Habermehl James L.
International Business Machines - Corporation
Psitos Aristotelis M.
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