The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 12, 2002
Filed:
May. 03, 1999
Ronald James Kadlec, Colorado Springs, CO (US);
Thomas James Frederick, Coconut Creek, FL (US);
Paul Henry Kelley, Boca Raton, FL (US);
Philip Saxton Weilbacher, Coconut Creek, FL (US);
Rodime PLC, Scotland, GB;
Abstract
A digital servo control system for disk drives is an “embedded” system—one in which servo control information is embedded on the same disk surface as the user data. In contrast to known embedded-servo systems in which a space-consuming series of many dibit pairs is present, the present system provides only a single dibit pair in a fractional positional error (PES ) area. Thus, the disk drive's read head encounters only a single dibit pair per sample period (or per data sector), thus saving valuable disk space that may be used for user data. Various pre-processing methods may be provided so as to pre-process the measurement derived from the single dibit pair per sample period (or data sector), so as to compensate for non-ideal characteristics of the dibit measurement. The system thus provides an accurate and robust servo control system, while sacrificing a minimum amount of valuable disk space to the servo information field.