Design of Modulation Code for Storage System: Basics, Concepts, Design Methods

Modulation code for optical recording systems have been concentrated on the combined DC-free and runlength-limited (RLL) code, in short DCRLL code. However, the design of high rate DCRLL code satisfying all of two constraints is far from obvious. Certainly, if channel is not free of errors, it is pointless to feed the sequences only satisfying RLL constraints. The weakly constrained coding scheme can accomplish the higher rate while it may relatively cause error in channel. The problem can be solved by designing the code with error correction capability. In this dissertation, in order to accomplish the above goals, low-density parity-check coded multimode code (LDPCCMC) and selection criteria are developed. The error control of LDPCCMC is conducted by the low-density parity-check (LDPC) code, and its high rate and DC-free properties are obtained by the design of multimode code using LDPC matrixes and the aid of selection criteria, respectively. I think that this research will be useful to anyone who may be interested in channel coding for storage system.