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:
Nov. 25, 1997
Filed:
Sep. 29, 1995
James Fitzpatrick, Mountain View, CA (US);
Xiaodong Che, Sunnyvale, CA (US);
Quantum Corporation, Milpitas, CA (US);
Abstract
Determining a micro-jog parameter in a disk drive that employs a magneto-resistive (MR) transducer head assembly and a partial response (PRML) detector includes improved accuracy in measuring on-track signal strength by use of a matched filter technique. The matched filter includes circuitry for emulating a partial response signal expected to be produced by a selected test bit pattern prerecorded on the selected track. The matched filtering technique provides improved accuracy in measuring the detected signal strength as it provides an extremely narrow digital filter focused on the test bit pattern frequency. Improved determination of the micro-jog distance further includes measuring interference from adjacent tracks, the best error rate being achieved at micro-jog positions intermediate the maximum on-track signal strength and the minimum off-track interference. A novel digital detector for accurately measuring adjacent track interference also is disclosed.