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:
Jun. 12, 2001
Filed:
Sep. 02, 1999
Shih-Ming Shih, San Jose, CA (US);
Hemant Thapar, San Jose, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
A system and method described for avoiding catastrophic error sequences in a media code sequence of symbols for data storage on a storage medium according to EPRML. The system and method includes modulation encoding user data which is to be stored on the storage medium using a modulation encoder. The modulation encoder outputs a channel code modulation output symbol sequence. The modulation code is defined according to a modulation criteria wherein the set of all possible modulation output symbol sequences is constrained in a manner which excludes certain excluded modulation output symbol sequences. A precoder precodes the channel code modulation output symbol sequence according to a precoding transfer function. The precoding transfer function transforms the channel code modulation output symbol sequence into a media code sequence of symbols and the precoding transfer function is defined so that when modulation encoding is performed according to the modulation criteria, the media code sequence of symbols is constrained to exclude EPRML catastrophic error sequences of greater than a determined length. The combination of the modulation encoding and the precoding prevents the media code sequence of symbols from including EPRML catastrophic error sequences greater than the determined length.