Modulation codes are used to constrain the individual sequences that are recorded in data storage channels, such as magnetic or optical disk or tape drives. The constraints are imposed in order to improve the detection capabilities of the system. Perhaps the most widely known constraints are the run length limited (RLL(d, k)) constraints, in which 1s are required to be separated by at least d and no more than k 0s. Such constraints are useful in data recording channels that employ peak detection: waveform peaks, corresponding to data ones, are detected independently of one another. The d-constraint helps to increase linear density while mitigating inter symbol interference, and the k-constraint helps to provide feedback for timing and gain control.
|Original language||English (US)|
|Title of host publication||Coding and Signal Processing for Magnetic Recording Systems|
|State||Published - Jan 1 2004|
All Science Journal Classification (ASJC) codes
- Computer Science(all)