METHOD AND APPARATUS FOR ENCODING A BINARY SIGNAL

摘要

A system and method for avoiding catastophic error sequences in a media code sequence of symbols for data storage on a storage medium according to EPRML. The system and method include modulation encoding user data which is to be stored on the storage medium using a modulation encoder (602). The modulation encoder (602) 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 (604) precodes the channel code modulation output symbol sequence to a precoding transfer function. The precoding transfer function transforms the channel code modulation output symbol sequence into a media code sequence of symboles 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 sequeces of greater than a determined length.