Code Design for Optical Storage - a Comparison to Magnetic Storage

Magnetic recording on disks and tapes has been successfully used for digital data storage for over 25 years. Binary digits (bits) are stored as the presence or absence of magnetization reversals along a track. During readback, the sequence of magnetization transitions induces a corresponding pulse train, from which the recorded bit string is recovered by detection of peak positions relative to time intervals generated by a synchronized clock.